Comparison of Perinatal Outcomes and Delivery Strategies in Pregnant Women with Idiopathic vs. Secondary Pulmonary Arterial Hypertension: A Retrospective Cohort Study

Comparison of Perinatal Outcomes and Delivery Strategies in Pregnant Women with Idiopathic vs. Secondary Pulmonary Arterial Hypertension: A Retrospective Cohort Study | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Comparison of Perinatal Outcomes and Delivery Strategies in Pregnant Women with Idiopathic vs. Secondary Pulmonary Arterial Hypertension: A Retrospective Cohort Study Lu Jiang, Fan Yang, Yiheng Tian, Yueheng Peng, Ying Zheng, Guolin He This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-7513096/v1 This work is licensed under a CC BY 4.0 License Status: Under Review Version 1 posted 8 You are reading this latest preprint version Abstract Objective: To compare the clinical characteristics, peripartum management, and maternal and fetal outcomes between pregnant women with idiopathic pulmonary arterial hypertension (iPAH) and those with secondary pulmonary arterial hypertension. Methods: This was a retrospective cohort study. A total of 184 pregnant patients with PAH were admitted to West China Second University Hospital from 2014–2024. Patients were divided into iPAH (n=46) and secondary PAH (n=138) groups on the basis of the etiology of PAH. Demographic and clinical data extracted from medical records included maternal demographics, clinical characteristics, mode of delivery, anesthesia methods, postpartum complications, and fetal/neonatal outcomes. Results: The median maternal age was 29.54 years, with 25% iPAH cases and 75% secondaryPAH cases. The majority (92.9%) were diagnosed during pregnancy. Compared with secondary PAH patients, iPAH patients had a greater average age (31.35 vs. 28.93 years, p =0.003) and BMI (26.05 vs. 24.15 kg/m 2 , p =0.003) but lower systolic pulmonary artery pressure (sPAP) (50.12 vs. 58.04 mmHg, p =0.008). Cesarean section was the predominant delivery method (99.3%), with 97.6% of iPAH patients and 91.1% of secondary PAH patients receiving spinal anesthesia. Intraoperative blood loss was greater in the iPAH group (539.29 vs. 388.31 mL, p <0.001). The overall in-hospital survival rate was 98.9%, with a maternal mortality rate of 1.1%. The fetal outcomes included a preterm birth rate of 52.9% and low birth weight in 49% of the neonates. No significant differences in neonatal outcomes were detected between the iPAH and secondary PAH groups. Conclusion: Despite multidisciplinary management improving survival, iPAH pregnancies are associated with increased maternal mortality and heart failure risks. Cesarean delivery with tailored hemostasis and cautious oxytocin use optimizes outcomes. Early prenatal screening, especially in high-risk women (advanced age, obesity), and phenotype-specific protocols are critical to mitigate risks. The limitations of this study include its retrospective design and echocardiography-based PAH diagnosis. Pulmonary arterial hypertension secondary pulmonary arterial hypertension idiopathic pulmonary arterial hypertension perinatal outcomes Introduction Pulmonary arterial hypertension (PAH), particularly idiopathic PAH (iPAH), represents a cardiopulmonary catastrophe during pregnancy, with maternal mortality rates exceeding 50% despite modern therapies 1 – 3 . This disease spectrum—encompassing iPAH, congenital heart disease-associated PAH (CHD-PAH), and other subtypes—is unified by pathological vascular remodeling but diverges in etiology: 20% of iPAH cases stem from bone morphogenetic protein receptor type 2 ( BMPR2) mutations driving endothelial dysfunction, whereas secondary PAH predominantly arises from inflammatory/mechanical insults or heart disease 4 , 5 . Alarmingly,30–60% of iPAH diagnoses are first established during gestation, coinciding with peak hemodynamic stress that unmasks subclinical disease 6 . Physiological adaptations, including 50% increase in plasma volume and 30–50% increase in cardiac output, become maladaptive in PAH patients. These changes trigger right ventricular failure in 50% of cases 7 , 8 . The WHO classifies this intersection as maternal risk category IV-V—the highest danger tier 9 . The risk of serious cardiovascular events during pregnancy ranges from 40%-100%, which is contraindicated during pregnancy 6 . Even optimal care cannot eliminate risks: prophylactic cesarean delivery under neuraxial anesthesia reduces acute afterload shifts but introduces hemorrhage risks 3 , 10 , whereas oxytocin prophylaxis remains a pharmacological tightrope walk owing to its pulmonary vasoreactivity 2 , 4 , 11 . Current evidence suffers from critical blind spots. While European registries suggest comparable outcomes between PAH subtypes (OR 1.22 for iPAH complications) 12 , Asian cohorts report 3-fold higher mortality in iPAH pregnancies 13 . This discrepancy may reflect delayed diagnosis in developing regions where echocardiography-based screening is inconsistent 7 , 12 . Furthermore, existing guidelines lack granularity for phenotype-specific management—a dangerous oversight given our recent finding that iPAH pregnant women require 40% higher targeted pulmonary vasodilator dosing than their secondary PAH counterparts 14 . Compared with pregnant women with other forms of PAH, pregnant women diagnosed with iPAH exhibit significant differences in clinical characteristics and pregnancy outcomes, particularly in developing regions 2 , 7 , 15 . This retrospective cohort study included 184 pregnant patients with PAH at West China Second University Hospital from 2014–2024. The primary objective was to characterize the clinical profiles and peripartum management of PAH, as well as the maternal and fetal outcomes in patients with PAH. The anticipated findings aim to enhance peripartum management, reduce perinatal morbidity and mortality, and improve long-term cardiovascular outcomes for women with PAH. Methods 2.1 Clinical Data Collection This study retrospectively analyzed the clinical data of 184 patients with PAH who were admitted to our hospital between January 2014 and December 2024. Patients who were delivered in our hospital and diagnosed by echocardiography with a systolic pulmonary artery pressure (sPAP) > 30 mmHg 4 were included. Patients born in other hospitals or who did not meet the diagnostic criteria for PH were excluded from this study. We divided pregnant women with PH into 2 groups: the iPAH group and the secondary PAH group (CHD-PAH, LHD-PAH, and other PAH). The outcomes of the mothers and fetuses were also analyzed. The clinical data collected included age, gravidity, parity, length of stay, ICU admission, length of ICU stay, body mass index (BMI), New York Heart Association (NYHA) functional class, systolic pulmonary artery pressure (sPAP), regular obstetric examinations, gestational age, mode of delivery, anesthesia method, postpartum complications, birth weight, fetal or neonatal status, Apgar scores, fetal and neonatal complications, NICU admission, perinatal mortality, and other relevant indicators. All patients were informed about the nature of the study. Patients or the public were not involved in the design, conduct, reporting, or dissemination plans of our research. In this study, it was inevitable that some clinical data would be incomplete; missing data were supplemented by telephone follow-up. The Ethics Committee of our hospital approved this study (The Institutional Review Board of West China Second University Hospital, approval number: 2025188), and all patients provided written informed consent. 2.2 Diagnosis of PAH According to the diagnostic criteria of the “2022 ESC/ERS Guidelines for the Diagnosis and Treatment of Pulmonary Hypertension”, the hemodynamic diagnostic criteria are a mean pulmonary artery pressure (sPAP) measured by right heart catheterization at sea level and at rest of ≥ 25 mmHg and a pulmonary artery wedge. pressure (PAWP) ≤ 15 mmHg and pulmonary vascular resistance (PVR) > 3 Wood units; the diagnostic criteria for iPAH should not only meet the PAH criteria but also exclude a family history of PAH and all possible secondary factors that may cause PAH. Strict diagnostic criteria should be based on right heart catheterization data. However, considering that right cardiac catheterization is an invasive examination, particularly for pregnant women, it is impossible to perform cardiac catheterization routinely to obtain pulmonary artery pressure in pregnant women 16 . In obstetrics, the sPAP is often indirectly evaluated by the tricuspid regurgitation pressure difference under cardiac color Doppler ultrasound, and an sPAP ≥ 30 mmHg (1 mmHg = 0.133 kPa) is used as the diagnostic standard for PAH 4 . Transthoracic echocardiography was performed for all patients. Patients were classified according to baseline resting systolic pulmonary artery pressure as mild PAH (sPAP 30–49 mmHg), moderate PAH (sPAP 50–79 mmHg), or severe PAH (sPAP ≥ 80 mmHg) 3 . 2.3 Statistical Analyses All analyses were performed via EXCEL and statistical software (version 25.0) (SPSS Inc., Chicago, IL, USA). Frequencies and percentages describe count data, and the significant differences among groups were compared by χ2 tests. The Shapiro‒Wilk (S‒W) test was used to test measurement data with a normal distribution; if the data conformed to a normal distribution, which is represented by the mean ± standard deviation (SD), Student’s t test was used for comparisons, and nonnormal data were analyzed via the Mann‒Whitney test. Categorical data are presented as frequencies and percentages, and chi-square tests were used for comparisons. P values of < 0.05 were considered statistically significant (two-sided test). Results 3.1 Clinical characteristics and underlying diseases in patients with PAH From January 2014 to December 2024, a total of 184 patients were included in this study, comprising 46 (25%) patients with iPAH and 138 (75%) patients with secondary PAH. The average maternal age was 29.54 years (± 4.885). The estimated sPAP among the patients indicated that 46.2% had a pressure of less than 50 mmHg, 39.7% had a pressure between 50 and 79 mmHg, and 14.1% had a pressure greater than 79 mmHg. Notably, in more than92.9% of the cases, the diagnosis of pulmonary hypertension (PH) was made during pregnancy. Most patients were transferred from other hospitals, so most of them did not receive targeted therapy before admission; however, all patients received protocolized care through a multidisciplinary team (MDT) immediately upon admission, comprising specialists from the departments of obstetrics, cardiology, anesthesiology, and ICU. The underlying diseases of PAH in the study population were CHD (60.9%), rheumatic heart disease (RHD, 10.9%), and iPAH (25%). Among the 6 patients (3.2%) in the other PAH group, 3 were diagnosed with systemic lupus erythematosus, 1 was diagnosed with constrictive pericarditis, 1 was diagnosed with Takayasu arteritis, and 1 was diagnosed with hyperthyroidism. Among patients with CHD or RHD, a total of 30 underwent surgery before pregnancy. Detailed information on these cases is shown in Table 1 . Table 1 Classification of pregnant women with PAH N % iPAH 46 25 Rheumatic heart disease 20 10.9 Predominate mitral stenosis 15 8.2 Mixed mitral diseases 2 1 Ebstein's anomaly 1 0.7 Prosthetic valves 2 1 Congenital heart disease 112 60.9 Atrial septal defect 62 33.7 Ventricular septal defect 15 8.3 ASD combined with VSD 10 5.4 Patent ductus arteriosus 13 7.1 Pulmonary stenosis 2 1 Anomalous pulmonary venous drainage 2 1 Transposition of the great arteries 1 0.7 Endocardial Cushion Defect 2 1 Tetralogy of Fallot 5 2.7 Other PAH 6 3.2 ASD, Atrial septal defect; VSD, ventricular septal defect. Overall, women with iPAH presented a significantly greater average age ( p = 0.003) and BMI than did those in the secondary PAH group ( p = 0.003). The sPAP values were lower in the iPAH group than in the secondary PAH group ( p = 0.008), and the proportion of patients with severe PAH was also significantly lower in the iPAH group ( p = 0.002). There were no significant differences between the two groups regarding gravidity, parity, length of hospital stay, length of ICU stay, timing of diagnosis, NYHA functional class, or regular obstetric examinations. The baseline characteristics are provided in Table 2 . Table 2 Maternal characteristics of patients with PAH. iPAH n = 46(%) secondary PAH n = 138(%) All n = 184 t/z/χ 2 P Age( years)(M ± SD) 31.35 ± 4.498 28.93 ± 4.875 29.54 ± 4.885 2.962 0.003 Gravidity(M ± SD) 2.5 ± 1.312 2.43 ± 1.708 2.45 ± 1.615 -0.952 0.341 Parity(M ± SD) 0.74 ± 0.905 0.55 ± 0.829 0.6 ± 0.85 -1.523 0.128 Length of stay (days), (M ± SD) 8.02 ± 4.919 8.34 ± 3.92 8.26 ± 4.18 -1.08 0.28 Length of ICU stay (M ± SD) 3.39 ± 4.435 3.3 ± 3.41 3.32 ± 3.68 -0.372 0.71 BMI(kg/m²)(M ± SD) 26.048 ± 3.594 24.15 ± 3.787 24.627 ± 3.82 2.974 0.003 Diagnosis made Before pregnancy 2(4.3) 11(8.0) 13(7.1) 0.523 0.324 During pregnancy 44(95.7) 127(92.0) 171(92.9) NYHA cardiac function classification, n (%) I-II 36(78.3) 96(69.6) 132(71.7) 1.287 0.257 III-IV 10(21.7) 42(30.4) 52(28.3) sPAP, Median(mmHg) (M ± SD) 50.12 ± 23.306 58.04 ± 21.615 56.17 ± 22.216 -2.666 0.008 PAH Grading Mild PAH 31(67.4) 54(39.1) 85(46.2) 12.267 0.002 Moderate PAH 9(19.6) 64(46.4) 73(39.7) Severe PAH 6(13.0) 20(14.5) 26(14.1) Regular obstetric examinations NO 6(13.0) 15(10.9) 21(11.4) 0.161 0.688 YES 40(87.0) 123(89.1) 163(88.6) sPAP, systolic pulmonary artery pressure values in mmHg; 3.2 Maternal and fetal/neonatal outcomes Maternal outcomes The in-hospital outcomes for pregnant women with PAH are summarized in Table 2 . The median gestational age at delivery was 228.15 days (interquartile range: ±49.449 days), whereas the mean gestational duration was significantly greater in patients with idiopathic pulmonary arterial hypertension (iPAH) (241.02 ± 42.606 days) than in secondary PAH controls (223.86 ± 50.95 days). When women with iPAH were compared with those with secondary PAH, the former group experienced significantly higher rates of heart failure (15.2% compared with 4.3%, p = 0.013). Among the patients, 152 (99.3%) underwent CS, with 45 (29.6%) undergoing emergency procedures; only 1 woman (0.7%) delivered vaginally. In this study, a total of 182 patients (98.9%) survived, while 2 patients (1.1%) died. Notably, there were no fatalities during pregnancy; both women died during the postpartum period. Neither of these patients had been diagnosed with pulmonary hypertension before pregnancy; both received diagnoses of iPAH during their hospitalization. Notably, these two patients were critically ill, had been transferred from other hospitals, and did not receive regular prenatal care throughout their pregnancies. Despite being provided with intensive medical support, their conditions worsened due to multiple organ dysfunction syndrome complicated by a PAH crisis, ultimately resulting in their deaths. Further detailed maternal outcomes can be found in Table 3 . Table 3 Maternal outcomes iPAH n = 46(%) secondary PAH n = 138(%) All n = 184 t/z/χ 2 P Delivery, median days of pregnancy (M ± SD) 241.02 ± 42.606 223.86 ± 50.95 228.15 ± 49.449 -2.882 0.004 Mode of delivery # cesarean section 40(97.6) 112(100.0) 152(99.3) 2.75 0.268 vaginal delivery 1(2.4) 0(0) 1(0.7) Postpartum hemorrhage No 43(93.5) 135(97.8) 178(96.7) 2.067 0.166 Yes 3(6.5) 3(2.2) 6(3.3) Heart failure NO 39(84.8) 132(95.7) 171(92.9) 6.208 0.013 YES 7(15.2) 6(4.3) 13(7.1) Death NO 44(95.7) 138(100) 182(98.9) 6.066 0.061 YES 2(4.3) 0(0) 2(1.1) #: 153 completed pregnancies. Fetal/neonatal outcomes Among 184 patients, 31 had therapeutic abortions, and 153 had live births. According to the severity of their conditions, among the 31 patients with iatrogenic abortion, 16 were subjected to CS abortions, and 15 received artificial abortions. Among the 153 newborns, 81 (52.9%) were preterm infants. Additionally, 75 infants (49%) had LBW, and 49 (32%) of the neonates were admitted to the NICU. Unfortunately, five neonates (3.1%) died within the first week after birth. The study compared fetal outcomes between the secondary PAH and iPAH groups and revealed significant differences in preterm birth and low birth weight ( p 0.05). Further detailed maternal and fetal/neonatal outcomes can be found in Table 4 . Table 4 Fetal/neonatal outcomes iPAH n = 46(%) secondary PAH n = 138(%) All n = 184 χ 2 P Premature infants (< 37 weeks)# No 27(65.9) 45(40.2) 72(47.1) 7.941 0.005 Yes 14(34.1) 67(59.8) 81(52.9) Admission to NICU# No 30(73.2) 74(66.1) 104(68.0) 0.695 0.405 Yes 11(26.8) 38(33.9) 49(32.0) Low birth weight (< 2500 g)# No 27(65.9) 51(45.5) 78(51.0) 4.958 0.026 Yes 14(34.1) 61(54.5) 75(49.0) Neonatal asphyxia# No 40(97.6) 103(92.0) 143(93.5) 1.539 0.29 Yes 1(2.4) 9(8.0) 10(6.5) Neonatal death(< 1 week)# No 39(95.1) 119(97.5) 158(96.9) 0.604 0.6 Yes 2(4.9) 3(2.5) 5(3.1) Fetal outcome Live birth 41(89.1) 112(81.2) 153 (83.2) 1.565 0.211 Abortion 5(10.9) 26(18.8) 31 (16.8) #: Fetal/neonatal outcomes in the 153 completed pregnancies. NICU: Neonatal intensive care unit 3.3 Management of pregnant women with PAH In this study, CS was the primary mode of childbirth for pregnant women with PAH. Among the patients who underwent cesarean termination, only 12 (7.2%) received general anesthesia, whereas 154 (92.8%) were administered spinal anesthesia. The comparative analysis revealed no significant differences between the two anesthesia groups. The average operative time for CS was 48.92 ± 19.756 minutes. Notably, the iPAH group had significantly longer operation times than did the secondary PAH group (57.0 ± 26.567 minutes vs. 46.18 ± 16.07 minutes, p = 0.001). Additionally, there were significant differences in intraoperative blood loss, with the iPAH group exhibiting a substantially greater hemorrhage volume (539.29 ± 348.084 mL vs. 388.307 ± 197.013 mL, p < 0.001). Given the limited use of uterine contraction agents in patients with PAH, achieving effective hemostasis during cesarean delivery is essential for preventing PPH. In the iPAH group, a larger proportion of patients (83.3% vs. 64.5%) utilized additional surgical techniques to minimize bleeding, such as ligation of the upper uterine arteries, uterine bundling, and the B-Lynch suture technique. As a result of these interventions, the incidence of PPH was only 3.3% (six patients). In this study, we used low-dose oxytocin to prevent PPH (10 U of oxytocin in 500 mL of normal saline given intravenously at 36 mL/hour for 4 hours (12 mU/min)). In total, 82.5% (137 patients) of the patients received oxytocin infusion during surgery to prevent hemorrhage. Furthermore, 86.4% (159 patients) initiated anticoagulation therapy on the first postoperative day. No significant differences were found between the two groups regarding intraoperative oxytocin use, anticoagulation therapy, ICU admission rates, or breastfeeding status. The detailed data can be found in Table 5 . Table 5 Management of pregnant women with PAH iPAH n = 46(%) secondary PAH n = 138(%) All n = 184 t/z/χ 2 P Way of anesthesia # 1.97 0.299 Spinal anesthesia 41(97.6) 113(91.1) 154(92.8) General anesthesia 1(2.4) 11(8.9) 12(7.2) Surgery time(minutes)(M ± SD) 57.0 ± 26.567 46.18 ± 16.075 48.92 ± 19.756 -3.378 0.001 Blood loss during CS(ml)(M ± SD) 539.29 ± 348.084 388.307 ± 197.013 426.506 ± 251.745 -3.883 < 0.001 Suturing techniques during CS # NO 7(16.7) 44(35.5) 51(30.7) 5.219 0.022 YES 35(83.3) 80(64.5) 115(69.3) Oxytocin use during CS # NO 8(19.0) 21(16.9) 29(17.5) 0.097 0.755 YES 34(81.0) 103(83.1) 137(82.5) Antithrombotic therapy NO 10(21.7) 15(10.9) 25(13.6) 3.472 0.062 Yes 36(78.3) 123(89.1) 159(86.4) Admission to ICU NO 17(37.0) 36(26.1) 53(28.8) 21.988 0.159 YES 29(63.0) 102(73.9) 131(71.2) Breastfeeding NO 35(76.1) 101(73.2) 136(73.9) 0.15 0.698 YES 11(23.9) 37(26.8) 48(26.1) #:168 patients who underwent CS Pulmonary Vasodilators In total, among these pregnancies, 11 (6.0%) were treated with PAH-targeted therapy: 2 (1.1%) received a combination of treprostinil and sildenafil before the pregnancy operation, while 9 (4.9%) were given pulmonary vasodilators before the operation—2 received treprostinil alone, and 7 were given treprostinil along with sildenafil. Discussion This retrospective cohort study analyzed 184 PAH-complicated pregnancies (46 iPAH pregnancies vs. 138 secondary PAH pregnancies) to delineate differential management strategies and maternal-fetal outcomes. The prevalence of PAH has risen markedly in recent decades, imposing a substantial societal disease burden 17 . Pregnancy exacerbates the disease burden associated with PAH, with a perinatal mortality rate as high as 3.3% 6 . IPAHs and secondary PAHs differ in their pathogenesis and clinical presentation 4 . Studies have shown a significant increase in the incidence of idiopathic pulmonary arterial hypertension (iPAH) during pregnancy, increasing from 3.3–25.6% to 59.6% 6,7,13,18 . The mortality rate for pregnant women with iPAH can reach 50%, which is far higher than that for those with secondary PAH 7 . The increasing incidence of iPAH during pregnancy underscores the necessity for tailored management strategies across PAH subtypes. Clinical feature variations In this study, the average age of patients in the iPAH group was 31.35 years (± 4.498), which was significantly greater than that of patients in the secondary PAH group at 28.93 years (± 4.875, p = 0.003). Additionally, the average BMI of the iPAH group was 26.048 kg/m 2 (± 3.594), which was also significantly greater than that of the secondary PAH group (24.15 kg/m 2 ) (± 3.787, p = 0.003). These findings suggest that advanced age and obesity may be independent risk factors for iPAH patients. This conclusion is consistent with the research results of Wahab et al. 19 , who noted that obesity-related cardiopulmonary diseases can significantly increase the risk of PAH. Obesity may lead to endothelial dysfunction and inflammatory responses, thereby exacerbating the pathophysiological process of PAH 20 . Moreover, advanced age itself may also be associated with degenerative changes in the cardiovascular system, further increasing the risk of developing PAH 21 , 22 . Notably, in the iPAH group, 92.9% of the patients were first diagnosed during pregnancy, indicating strong concealment of iPAH. In contrast, the majority of cases in the secondary PAH group were related to congenital heart disease (CHD-PAH, accounting for 60.9%), and these patients often have a clear cardiovascular disease foundation before pregnancy 18 , 23 , 24 . The concealment of iPAH means that patients diagnosed during pregnancy face greater risks because the condition may have already progressed to a more severe stage at this time. Therefore, for high-risk groups, especially women of advanced age and with high BMIs, increasing the frequency of prenatal screening is particularly important. By increasing the frequency of examinations such as echocardiography, potential PAH patients can be identified earlier, allowing timely intervention and management to reduce the risk of adverse outcomes for both mothers and fetuses. Comparison of perioperative management strategies In this study, both the iPAH and secondary PAH groups presented a high CS rate (99.3%). However, the iPAH group had a significantly longer surgical time (57.0 ± 26.567 minutes vs. 46.18 ± 16.07 minutes, p = 0.001) and greater intraoperative blood loss (539.29 ± 348.084 mL vs. 388.307 ± 197.013 mL, p < 0.001). These differences may be due to the greater vulnerability of right heart function to volume load fluctuations in iPAH patients, which requires more precise hemodynamic management during surgery. To address the increased risk of bleeding, the iPAH group more frequently employed prophylactic hemostatic techniques (83.3% vs. 64.5%, p = 0.022), such as uterine artery ligation and B-Lynch suturing. Current guidelines recommend prophylactic hemostatic measures for high-risk PPH patients 25 , 26 . This proactive approach contributes to a lower PPH rate of 3.3% in the iPAH group, which is better than the 10%-15% reduction reported in previous studies. In this study, both groups predominantly utilized neuraxial anesthesia (92.8%), reflecting its widespread application in cesarean deliveries for PAH patients. This preference stems from the ability of neuraxial anesthesia to provide stable hemodynamic control and reduce the risk of intraoperative and postoperative complications. However, despite the similarity in anesthesia methods, a significant difference was observed in the postoperative use of oxytocin between the two groups. Nonetheless, our study validated the safety of low-dose oxytocin (12 mU/min) as a preventive strategy against postpartum hemorrhage in PAH patients. Compared with the secondary PAH group, the iPAH group had a significantly lower rate of oxytocin use (81.0% vs. 83.1%, p = 0.755). The results indicated no statistically significant difference in PPH risk between the two groups when low-dose oxytocin was combined with prophylactic hemostatic techniques (6.5% vs. 2.2%, p = 0.166). The use of oxytocin in PAH patients remains a contentious clinical dilemma 27 . Oxytocin may exacerbate pulmonary hypertension through dual mechanisms: pulmonary vasoconstriction elevates pulmonary artery pressure, and systemic vasodilation reduces right ventricular preload, potentially precipitating right heart failure 2 . Zhang et al. reported that the use of oxytocin in iPAH patients was associated with a significant increase in sPAP, leading to the discontinuation of oxytocin use. However, it should be noted that the subjects included in that study were all patients with severe iPAH, and the dose of oxytocin used was 10 U. However, Shu et al. 28 reported that the use of oxytocin in PAH patients is safe. The use of low-dose oxytocin (12 mU/min) in PAH patients can effectively prevent PPH, with no adverse outcomes, such as heart failure, occurring 29 , 30 . The relevant guidelines do not explicitly prohibit the use of oxytocin in PAH patients but emphasize the risk of right ventricular failure and a low-output state. The combination of low-dose oxytocin infusion and prophylactic surgical hemostatic measures is effective in reducing the risk of bleeding after cesarean section. However, its use should be carefully considered on the basis of the individual patient's condition. Maternal outcomes In our study, the iPAH group presented a 3.5-fold greater incidence of heart failure (15.2% vs. 4.3%, p = 0.013), and mortality was concentrated in the severe PAH subgroup (4.3% vs. 0%), driven by irreversible pulmonary vascular remodeling and right ventricular decompensation exacerbated by pregnancy-induced volume overload. In contrast, secondary PAH patients demonstrated hemodynamic reversibility through preconception shunt correction, enhancing cardiac reserve and reducing acute failure risk. Mortality rates across studies show a downward trend (0.51% in large cohorts vs. 17.6% in Zhang et al.) 1,2 , with our study reporting 1.1% mortality, attributed to early detection and improved management. Liu et al.'s study further revealed that iPAH has a mortality rate of 33.3%, which significantly exceeds that reported for secondary PAH subtypes. However, in both their study and the present research, all deceased patients had severe PAH. These findings underscore that iPAH patients’ right ventricles exhibit extreme sensitivity to volume loading, necessitating stricter peripartum hemodynamic monitoring. Severe PAH confers prohibitive maternal risk, which warrants prepregnancy counseling for avoidance or termination 8 , 18 , 31 . Fetal/neonatal outcomes Additionally, patients with PAH are at increased risk for adverse fetal outcomes. Sliwa et al. 6 reported that the neonatal mortality rate was 9.3% within the first week of life, and 20% of neonates born to patients with PAH were small for gestational age, with 4% having some form of cardiac anomaly. In our study, 31 patients underwent medically indicated abortions because they were unsuitable for pregnancy. Among the 153 live births, 81 (52.9%) were preterm infants, with a greater proportion observed in the secondary PAH group. This may be related to guidelines recommending pregnancy termination at 32–34 weeks for severe heart disease 4 , 16 . Therefore, the greater proportion of preterm infants in the secondary PAH group may be related to the results of this study. Planned CS ensures maternal and fetal safety, with no maternal deaths in the secondary PAH group. Close antenatal monitoring likely contributed to the low neonatal asphyxia and mortality rates, which were lower than those reported in the literature. Limitations This study, as a single-center retrospective analysis with diagnoses primarily based on echocardiography, may underestimate the severity of PAH 16 . Additionally, the lack of long-term follow-up data limits the evaluation of neonates' extended prognoses. Future investigations should adopt multicenter prospective designs incorporating right heart catheterization and genetic profiling (including BMPR2 mutation screening) to classify PAH subtypes precisely and establish phenotype-specific management protocols. Conclusion Management of iPAH and secondary PAH pregnancies demands subtype-tailored approaches. For iPAH, the clinical focus should focus on early screening in advanced-age or obese populations, intraoperative hemostatic precision, and optimized dosing of targeted pulmonary vasodilators. In contrast, secondary PAH management requires prioritization of primary disease control (e.g., congenital heart defect repair) and risk-stratified pregnancy termination timing. Low-dose oxytocin combined with prophylactic surgical hemostasis is safe for both subtypes but necessitates rigorous individualized risk‒benefit analysis. Crucially, MDT coordination remains pivotal for improving maternal–fetal outcomes. Declarations Funding: This study was supported by the National Key R&D Program of China (grant number 2022YFC2704103) and the National Key Research and Development Program of China (2021YFC2701501). This work was not associated with any commercial entity. Ethics approval and consent to participate This study was approved by the Ethics Committee of West China Second University Hospital of Sichuan University (No. 2025188) and conducted according to ICMJE recommendations. Consent for publication All participants provided informed consent. Availability of data and materials Owing to privacy and ethical concerns, the data cannot be made publicly available. However, these data are available from the corresponding author upon reasonable request. Competing interests The authors declare that they have no competing interests. Funding No funding Authors' contributions All the authors contributed to and participated in the preparation of the manuscript and research steps in the present study as follows: Conception and design of the research—Lu Jiang, Fan Yang, Yueheng Peng, Ying Zheng and Guolin He ; acquisition of data collection and statistical analysis—Lu Jiang and Yiheng Tian; writing of original draft—Lu Jiang ; Reading, Revising and Final approval for submission—All. Acknowledgment The authors thank all the participants of this study. References Agrawal A, Bajaj S, Bhagat U, Yesilyaprak A, Chandna S, Arockiam AD, Jamil Y, El Iskandarani M, Gupta R, Majid M, Nayar D, Michos ED. Cardiovascular Complications With Delivery Hospitalizations in Patients With Pulmonary Hypertension: A Nationwide Study From 2011 to 2020. JAHA 2024; 13 :e031632. Zhang J, Lu J, Zhou X, Xu X, Ye Q, Ou Q, Li Y, Huang J. 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Jerjes-Sánchez C, Ramírez-Rivera A, Hernandez NZ, Cueto Robledo G, García-Aguilar H, Gutiérrez-Fajardo P, Seoane García de León M, Moreno Hoyos-Abril F, Ernesto Beltrán Gámez M, Elizalde J, Fccp TP, Sandoval J, REMEHIP Investigators. Demographic, hemodynamic characteristics, and therapeutic trends of pulmonary hypertension patients: The Pulmonary Hypertension Mexican registry (REMEHIP). Pulm Circ 2024; 14 :e12395. Sliwa K, Hagen IM van, Budts W, Swan L, Sinagra G, Caruana M, Blanco MV, Wagenaar LJ, Johnson MR, Webb G, Hall R, Roos-Hesselink JW. Pulmonary hypertension and pregnancy outcomes: data from the Registry Of Pregnancy and Cardiac Disease (ROPAC) of the European Society of Cardiology. European Journal of Heart Failure 2016. Lv C, Huang Y, Liao G, Wu L, Chen D, Gao Y. Pregnancy outcomes in women with pulmonary hypertension: a retrospective study in China. BMC Pregnancy Childbirth 2023; 23 :16. Krishnathasan K, Constantine A, Rafiq I, Barradas Pires A, Douglas H, Price LC, Dimopoulos K. Management of pulmonary arterial hypertension during pregnancy. Expert Review of Respiratory Medicine 2023; 17 :413–423. Hagen IM van, Roos-Hesselink JW. Pregnancy in congenital heart disease: risk prediction and counseling. Heart 2020; 106 :1853–1861. Barańska-Pawełczak K, Wojciechowska C, Jacheć W. Pregnancy in Patients with Pulmonary Arterial Hypertension in Light of New ESC Guidelines on Pulmonary Hypertension. IJERPH 2023; 20 :4625. Badlam JB, Badesch DB, Austin ED, Benza RL, Chung WK, Farber HW, Feldkircher K, Frost AE, Poms AD, Lutz KA, Pauciulo MW, Yu C, Nichols WC, Elliott CG, USPHSR Investigators. United States Pulmonary Hypertension Scientific Registry: Baseline Characteristics. Chest 2021; 159 :311–327. Thomas E, Yang J, Xu J, Lima FV, Stergiopoulos K. Pulmonary Hypertension and Pregnancy Outcomes: Insights From the National Inpatient Sample. JAHA 2017; 6 :e006144. Liu Y, Li H, Li Y, Zhang J, Gu H, Wang J, Wang Q. Outcomes of pregnancy in women with different types of pulmonary hypertension. BMC Cardiovascular Disorders 2023; 23 :391. Hoeper MM. Idiopathic pulmonary arterial hypertension phenotypes determined by cluster analysis from the COMPERA registry Fan C, Liu X, Liu R, Zhang Y, Hao P. Pregnancy conditions and outcomes of Chinese women with mild, moderate and severe pulmonary arterial hypertension. Hypertens Res 2024; 47 :2561–2573. Teng Y, Zong L, Ding J, Wu M, Li X. Management of pulmonary arterial hypertension：before, during and after pregnancy. International Journal of Cardiology Cardiovascular Risk and Prevention 2024; 21 :200252. Global, regional, and national burden of pulmonary arterial hypertension, 1990–2021: a systematic analysis for the Global Burden of Disease Study 2021. Lancet Respir Med 2025; 13 :69–79. Shi Y, Wu D, Chen L, Shi Y. Analysis of the clinical characteristics and outcomes of pregnant women with different degrees of pulmonary hypertension. J Matern Fetal Neonatal Med 2025; 38 :2352090. Wahab A, Dey AK, Bandyopadhyay D, Katikineni V, Chopra R, Vedantam KS, Devraj M, Chowdary AK, Navarengom K, Lavie CJ, Kolpakchi A, Jneid H. Obesity, Systemic Hypertension, and Pulmonary Hypertension: A Tale of Three Diseases. Curr Probl Cardiol 2021; 46 :100599. Ramlakhan KP, Malhamé I, Marelli A, Rutz T, Goland S, Franx A, Sliwa K, Elkayam U, Johnson MR, Hall R, Cornette J, Roos-Hesselink JW. Hypertensive disorders of pregnant women with heart disease: the ESC EORP ROPAC Registry. Eur Heart J 2022; 43 :3749–3761. Hoeper MM, Dwivedi K, Pausch C, Lewis RA, Olsson KM, Huscher D, Pittrow D, Grünig E, Staehler G, Vizza CD, Gall H, Distler O, Opitz C, Gibbs JSR, Delcroix M, Park D-H, Ghofrani HA, Ewert R, Kaemmerer H, Kabitz H-J, Skowasch D, Behr J, Milger K, Lange TJ, Wilkens H, Seyfarth H-J, Held M, Dumitrescu D, Tsangaris I, Vonk-Noordegraaf A, Ulrich S, Klose H, Claussen M, Eisenmann S, Schmidt K-H, Swift AJ, Thompson AAR, Elliot CA, Rosenkranz S, Condliffe R, Kiely DG, Halank M. Phenotyping of idiopathic pulmonary arterial hypertension: a registry analysis. Lancet Respir Med 2022; 10 :937–948. Ling Y, Johnson MK, Kiely DG, Condliffe R, Elliot CA, Gibbs JSR, Howard LS, Pepke-Zaba J, Sheares KKK, Corris PA, Fisher AJ, Lordan JL, Gaine S, Coghlan JG, Wort SJ, Gatzoulis MA, Peacock AJ. Changing demographics, epidemiology, and survival of incident pulmonary arterial hypertension: results from the pulmonary hypertension registry of the United Kingdom and Ireland. Am J Respir Crit Care Med 2012; 186 :790–796. Liu Y, Li Y, Zhang J, Zhang D, Li J, Zhao Y, Liu K, Ma X, Bai C, Gu H, Fan X, Wang J. Maternal and fetal outcomes of pregnant women with pulmonary arterial hypertension associated with congenital heart disease in Beijing, China: A retrospective study. Pulm Circ 2022; 12 :e12079. Park E, Safdar Z. Pulmonary Hypertension in Women. Methodist Debakey Cardiovasc J 2024; 20 :70–80. Oyelese Y, Ananth CV. Postpartum hemorrhage: epidemiology, risk factors, and causes. Clin Obstet Gynecol 2010; 53 :147–156. Escobar MF, Nassar AH, Theron G, Barnea ER, Nicholson W, Ramasauskaite D, Lloyd I, Chandraharan E, Miller S, Burke T, Ossanan G, Andres Carvajal J, Ramos I, Hincapie MA, Loaiza S, Nasner D, FIGO Safe Motherhood and Newborn Health Committee. FIGO recommendations on the management of postpartum hemorrhage 2022. Int J Gynecol Obstet 2022; 157 Suppl 1 :3–50. Yamaguchi ET, Cardoso MMSC, Torres MLA. Oxytocin in cesarean sections: what is the best way to use it? Rev Bras Anestesiol 2007; 57 :324–350. Shu T, Feng P, Liu X, Wen L, Chen H, Chen Y, Huang W. Multidisciplinary Team Managements and Clinical Outcomes in Patients With Pulmonary Arterial Hypertension During the Perinatal Period. Front Cardiovasc Med 2021; 8 :795765. Cauldwell M, Steer PJ, Swan L, Uebing A, Gatzoulis MA, Johnson MR. The management of the third stage of labor in women with heart disease. Heart 2017; 103 :945–951. Baliuliene V, Vitartaite M, Rimaitis K. Prophylactic Dose of Oxytocin for Uterine Atony during CesareanDelivery: A Systematic Review. Int J Environ Res Public Health 2021; 18 :5029. Boyers S, Nayyar R, Melov SJ, Tanous D, Brown J. A case series describing the multidisciplinary management of pulmonary arterial hypertension in pregnancy: Time for optimism. Aust N Z J Obstet Gynecol 2023; 63 :66–73. Additional Declarations No competing interests reported. Cite Share Download PDF Status: Under Review Version 1 posted Reviewers agreed at journal 08 Nov, 2025 Reviews received at journal 02 Nov, 2025 Reviewers agreed at journal 30 Oct, 2025 Reviewers invited by journal 30 Oct, 2025 Editor assigned by journal 28 Oct, 2025 Editor invited by journal 08 Oct, 2025 Submission checks completed at journal 07 Oct, 2025 First submitted to journal 07 Oct, 2025 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-7513096","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":542177738,"identity":"c71232d6-c67f-4075-a40d-aa55532430b1","order_by":0,"name":"Lu Jiang","email":"","orcid":"","institution":"Sichuan University West China Second University Hospital Department of Obstetrics and Gynecology","correspondingAuthor":false,"prefix":"","firstName":"Lu","middleName":"","lastName":"Jiang","suffix":""},{"id":542177740,"identity":"6980cae0-20fa-4813-b928-3813a9d3dad6","order_by":1,"name":"Fan Yang","email":"","orcid":"","institution":"Sichuan University West China Second University Hospital Department of Obstetrics and Gynecology","correspondingAuthor":false,"prefix":"","firstName":"Fan","middleName":"","lastName":"Yang","suffix":""},{"id":542177741,"identity":"929a1438-816b-45b5-aebc-ae60192655a2","order_by":2,"name":"Yiheng Tian","email":"","orcid":"","institution":"Sichuan University West China Second University Hospital Department of Obstetrics and Gynecology","correspondingAuthor":false,"prefix":"","firstName":"Yiheng","middleName":"","lastName":"Tian","suffix":""},{"id":542177744,"identity":"94cc6404-d852-41ba-b0b2-5edb9444817c","order_by":3,"name":"Yueheng Peng","email":"","orcid":"","institution":"Clinical Hospital of Chengdu Brain Science Institute, University of Electronic Science and Technology of China","correspondingAuthor":false,"prefix":"","firstName":"Yueheng","middleName":"","lastName":"Peng","suffix":""},{"id":542177745,"identity":"cada56df-49d4-4454-bfbd-9f02706c34c8","order_by":4,"name":"Ying 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class=\"CitationRef\"\u003e3\u003c/span\u003e\u003c/sup\u003e. This disease spectrum—encompassing iPAH, congenital heart disease-associated PAH (CHD-PAH), and other subtypes—is unified by pathological vascular remodeling but diverges in etiology: 20% of iPAH cases stem from bone morphogenetic protein receptor type 2 \u003cb\u003e(\u003c/b\u003eBMPR2) mutations driving endothelial dysfunction, whereas secondary PAH predominantly arises from inflammatory/mechanical insults or heart disease \u003csup\u003e\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e,\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e\u003c/sup\u003e. Alarmingly,30–60% of iPAH diagnoses are first established during gestation, coinciding with peak hemodynamic stress that unmasks subclinical disease \u003csup\u003e\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e\u003c/sup\u003e.\u003c/p\u003e\u003cp\u003ePhysiological adaptations, including 50% increase in plasma volume and 30–50% increase in cardiac output, become maladaptive in PAH patients. These changes trigger right ventricular failure in 50% of cases \u003csup\u003e\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e,\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e\u003c/sup\u003e. The WHO classifies this intersection as maternal risk category IV-V—the highest danger tier \u003csup\u003e\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e\u003c/sup\u003e. The risk of serious cardiovascular events during pregnancy ranges from 40%-100%, which is contraindicated during pregnancy \u003csup\u003e\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e\u003c/sup\u003e. Even optimal care cannot eliminate risks: prophylactic cesarean delivery under neuraxial anesthesia reduces acute afterload shifts but introduces hemorrhage risks \u003csup\u003e\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e,\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e\u003c/sup\u003e, whereas oxytocin prophylaxis remains a pharmacological tightrope walk owing to its pulmonary vasoreactivity \u003csup\u003e\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e,\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e,\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e\u003c/sup\u003e.\u003c/p\u003e\u003cp\u003eCurrent evidence suffers from critical blind spots. While European registries suggest comparable outcomes between PAH subtypes (OR 1.22 for iPAH complications) \u003csup\u003e\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e\u003c/sup\u003e, Asian cohorts report 3-fold higher mortality in iPAH pregnancies \u003csup\u003e\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e\u003c/sup\u003e. This discrepancy may reflect delayed diagnosis in developing regions where echocardiography-based screening is inconsistent \u003csup\u003e\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e,\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e\u003c/sup\u003e. Furthermore, existing guidelines lack granularity for phenotype-specific management—a dangerous oversight given our recent finding that iPAH pregnant women require 40% higher targeted pulmonary vasodilator dosing than their secondary PAH counterparts \u003csup\u003e\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e\u003c/sup\u003e.\u003c/p\u003e\u003cp\u003eCompared with pregnant women with other forms of PAH, pregnant women diagnosed with iPAH exhibit significant differences in clinical characteristics and pregnancy outcomes, particularly in developing regions \u003csup\u003e\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e,\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e,\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e\u003c/sup\u003e. This retrospective cohort study included 184 pregnant patients with PAH at West China Second University Hospital from 2014–2024. The primary objective was to characterize the clinical profiles and peripartum management of PAH, as well as the maternal and fetal outcomes in patients with PAH. The anticipated findings aim to enhance peripartum management, reduce perinatal morbidity and mortality, and improve long-term cardiovascular outcomes for women with PAH.\u003c/p\u003e"},{"header":"Methods","content":"\u003ch2\u003e2.1 Clinical Data Collection\u003c/h2\u003e\u003cp\u003eThis study retrospectively analyzed the clinical data of 184 patients with PAH who were admitted to our hospital between January 2014 and December 2024. Patients who were delivered in our hospital and diagnosed by echocardiography with a systolic pulmonary artery pressure (sPAP) \u0026gt; 30 mmHg \u003csup\u003e\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e\u003c/sup\u003e were included. Patients born in other hospitals or who did not meet the diagnostic criteria for PH were excluded from this study. We divided pregnant women with PH into 2 groups: the iPAH group and the secondary PAH group (CHD-PAH, LHD-PAH, and other PAH). The outcomes of the mothers and fetuses were also analyzed. The clinical data collected included age, gravidity, parity, length of stay, ICU admission, length of ICU stay, body mass index (BMI), New York Heart Association (NYHA) functional class, systolic pulmonary artery pressure (sPAP), regular obstetric examinations, gestational age, mode of delivery, anesthesia method, postpartum complications, birth weight, fetal or neonatal status, Apgar scores, fetal and neonatal complications, NICU admission, perinatal mortality, and other relevant indicators. All patients were informed about the nature of the study. Patients or the public were not involved in the design, conduct, reporting, or dissemination plans of our research. In this study, it was inevitable that some clinical data would be incomplete; missing data were supplemented by telephone follow-up. The Ethics Committee of our hospital approved this study (The Institutional Review Board of West China Second University Hospital, approval number: 2025188), and all patients provided written informed consent.\u003c/p\u003e\u003ch2\u003e2.2 Diagnosis of PAH\u003c/h2\u003e\u003cp\u003e According to the diagnostic criteria of the “2022 ESC/ERS Guidelines for the Diagnosis and Treatment of Pulmonary Hypertension”, the hemodynamic diagnostic criteria are a mean pulmonary artery pressure (sPAP) measured by right heart catheterization at sea level and at rest of ≥ 25 mmHg and a pulmonary artery wedge.\u003c/p\u003e\u003cp\u003epressure (PAWP) ≤ 15 mmHg and pulmonary vascular resistance (PVR) \u0026gt; 3 Wood units; the diagnostic criteria for iPAH should not only meet the PAH criteria but also exclude a family history of PAH and all possible secondary factors that may cause PAH. Strict diagnostic criteria should be based on right heart catheterization data. However, considering that right cardiac catheterization is an invasive examination, particularly for pregnant women, it is impossible to perform cardiac catheterization routinely to obtain pulmonary artery pressure in pregnant women \u003csup\u003e\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e\u003c/sup\u003e. In obstetrics, the sPAP is often indirectly evaluated by the tricuspid regurgitation pressure difference under cardiac color Doppler ultrasound, and an sPAP ≥ 30 mmHg (1 mmHg = 0.133 kPa) is used as the diagnostic standard for PAH \u003csup\u003e\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e\u003c/sup\u003e. Transthoracic echocardiography was performed for all patients. Patients were classified according to baseline resting systolic pulmonary artery pressure as mild PAH (sPAP 30–49 mmHg), moderate PAH (sPAP 50–79 mmHg), or severe PAH (sPAP ≥ 80 mmHg) \u003csup\u003e\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e\u003c/sup\u003e.\u003c/p\u003e\u003ch2\u003e2.3 Statistical Analyses\u003c/h2\u003e\u003cp\u003eAll analyses were performed via EXCEL and statistical software (version 25.0) (SPSS Inc., Chicago, IL, USA). Frequencies and percentages describe count data, and the significant differences among groups were compared by χ2 tests. The Shapiro‒Wilk (S‒W) test was used to test measurement data with a normal distribution; if the data conformed to a normal distribution, which is represented by the mean ± standard deviation (SD), Student’s \u003cem\u003et\u003c/em\u003e test was used for comparisons, and nonnormal data were analyzed via the Mann‒Whitney test. Categorical data are presented as frequencies and percentages, and chi-square tests were used for comparisons. \u003cem\u003eP\u003c/em\u003e values of \u0026lt; 0.05 were considered statistically significant (two-sided test).\u003c/p\u003e"},{"header":"Results","content":"\u003cdiv id=\"Sec6\" class=\"Section2\"\u003e\u003ch2\u003e3.1 Clinical characteristics and underlying diseases in patients with PAH\u003c/h2\u003e\u003cp\u003eFrom January 2014 to December 2024, a total of 184 patients were included in this study, comprising 46 (25%) patients with iPAH and 138 (75%) patients with secondary PAH. The average maternal age was 29.54 years (\u0026plusmn;\u0026thinsp;4.885). The estimated sPAP among the patients indicated that 46.2% had a pressure of less than 50 mmHg, 39.7% had a pressure between 50 and 79 mmHg, and 14.1% had a pressure greater than 79 mmHg. Notably, in more than92.9% of the cases, the diagnosis of pulmonary hypertension (PH) was made during pregnancy. Most patients were transferred from other hospitals, so most of them did not receive targeted therapy before admission; however, all patients received protocolized care through a multidisciplinary team (MDT) immediately upon admission, comprising specialists from the departments of obstetrics, cardiology, anesthesiology, and ICU.\u003c/p\u003e\u003cp\u003eThe underlying diseases of PAH in the study population were CHD (60.9%), rheumatic heart disease (RHD, 10.9%), and iPAH (25%). Among the 6 patients (3.2%) in the other PAH group, 3 were diagnosed with systemic lupus erythematosus, 1 was diagnosed with constrictive pericarditis, 1 was diagnosed with Takayasu arteritis, and 1 was diagnosed with hyperthyroidism. Among patients with CHD or RHD, a total of 30 underwent surgery before pregnancy. Detailed information on these cases is shown in Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e.\u003c/p\u003e\u003cp\u003e\u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab1\" border=\"1\"\u003e\u003ccaption language=\"En\"\u003e\u003cdiv class=\"CaptionNumber\"\u003eTable 1\u003c/div\u003e\u003cdiv class=\"CaptionContent\"\u003e\u003cp\u003eClassification of pregnant women with PAH\u003c/p\u003e\u003c/div\u003e\u003c/caption\u003e\u003ccolgroup cols=\"3\"\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/th\u003e\u003cth align=\"left\" colname=\"c2\"\u003e\u003cp\u003eN\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c3\"\u003e\u003cp\u003e%\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eiPAH\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e46\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e25\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eRheumatic heart disease\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e20\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e10.9\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003ePredominate mitral stenosis\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e15\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e8.2\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eMixed mitral diseases\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e2\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e1\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eEbstein's anomaly\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e0.7\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eProsthetic valves\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e2\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e1\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eCongenital heart disease\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e112\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e60.9\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eAtrial septal defect\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e62\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e33.7\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eVentricular septal defect\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e15\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e8.3\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eASD combined with VSD\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e10\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e5.4\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003ePatent ductus arteriosus\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e13\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e7.1\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003ePulmonary stenosis\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e2\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e1\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eAnomalous pulmonary venous drainage\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e2\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e1\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eTransposition of the great arteries\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e0.7\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eEndocardial Cushion Defect\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e2\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e1\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eTetralogy of Fallot\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e5\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e2.7\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eOther PAH\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e6\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e3.2\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e\u003cp\u003eASD, Atrial septal defect; VSD, ventricular septal defect.\u003c/p\u003e\u003cp\u003eOverall, women with iPAH presented a significantly greater average age (\u003cem\u003ep\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.003) and BMI than did those in the secondary PAH group (\u003cem\u003ep\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.003). The sPAP values were lower in the iPAH group than in the secondary PAH group (\u003cem\u003ep\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.008), and the proportion of patients with severe PAH was also significantly lower in the iPAH group (\u003cem\u003ep\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.002). There were no significant differences between the two groups regarding gravidity, parity, length of hospital stay, length of ICU stay, timing of diagnosis, NYHA functional class, or regular obstetric examinations. The baseline characteristics are provided in Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e.\u003c/p\u003e\u003cp\u003e\u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab2\" border=\"1\"\u003e\u003ccaption language=\"En\"\u003e\u003cdiv class=\"CaptionNumber\"\u003eTable 2\u003c/div\u003e\u003cdiv class=\"CaptionContent\"\u003e\u003cp\u003eMaternal characteristics of patients with PAH.\u003c/p\u003e\u003c/div\u003e\u003c/caption\u003e\u003ccolgroup cols=\"6\"\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/th\u003e\u003cth align=\"left\" colname=\"c2\"\u003e\u003cp\u003eiPAH\u003c/p\u003e\u003cp\u003en\u0026thinsp;=\u0026thinsp;46(%)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c3\"\u003e\u003cp\u003esecondary PAH n\u0026thinsp;=\u0026thinsp;138(%)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c4\"\u003e\u003cp\u003eAll\u003c/p\u003e\u003cp\u003en\u0026thinsp;=\u0026thinsp;184\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c5\"\u003e\u003cp\u003e\u003cem\u003et/z/χ\u003c/em\u003e\u003csup\u003e2\u003c/sup\u003e\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c6\"\u003e\u003cp\u003e\u003cem\u003eP\u003c/em\u003e\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eAge( years)(M\u0026thinsp;\u0026plusmn;\u0026thinsp;SD)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e31.35\u0026thinsp;\u0026plusmn;\u0026thinsp;4.498\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e28.93\u0026thinsp;\u0026plusmn;\u0026thinsp;4.875\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e29.54\u0026thinsp;\u0026plusmn;\u0026thinsp;4.885\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e2.962\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e\u003cb\u003e0.003\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eGravidity(M\u0026thinsp;\u0026plusmn;\u0026thinsp;SD)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e2.5\u0026thinsp;\u0026plusmn;\u0026thinsp;1.312\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e2.43\u0026thinsp;\u0026plusmn;\u0026thinsp;1.708\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e2.45\u0026thinsp;\u0026plusmn;\u0026thinsp;1.615\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e-0.952\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e0.341\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eParity(M\u0026thinsp;\u0026plusmn;\u0026thinsp;SD)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e0.74\u0026thinsp;\u0026plusmn;\u0026thinsp;0.905\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e0.55\u0026thinsp;\u0026plusmn;\u0026thinsp;0.829\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e0.6\u0026thinsp;\u0026plusmn;\u0026thinsp;0.85\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e-1.523\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e0.128\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eLength of stay (days), (M\u0026thinsp;\u0026plusmn;\u0026thinsp;SD)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e8.02\u0026thinsp;\u0026plusmn;\u0026thinsp;4.919\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e8.34\u0026thinsp;\u0026plusmn;\u0026thinsp;3.92\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e8.26\u0026thinsp;\u0026plusmn;\u0026thinsp;4.18\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e-1.08\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e0.28\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eLength of ICU stay (M\u0026thinsp;\u0026plusmn;\u0026thinsp;SD)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e3.39\u0026thinsp;\u0026plusmn;\u0026thinsp;4.435\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e3.3\u0026thinsp;\u0026plusmn;\u0026thinsp;3.41\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e3.32\u0026thinsp;\u0026plusmn;\u0026thinsp;3.68\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e-0.372\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e0.71\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eBMI(kg/m\u0026sup2;)(M\u0026thinsp;\u0026plusmn;\u0026thinsp;SD)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e26.048\u0026thinsp;\u0026plusmn;\u0026thinsp;3.594\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e24.15\u0026thinsp;\u0026plusmn;\u0026thinsp;3.787\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e24.627\u0026thinsp;\u0026plusmn;\u0026thinsp;3.82\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e2.974\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e\u003cb\u003e0.003\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eDiagnosis made\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eBefore pregnancy\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e2(4.3)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e11(8.0)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e13(7.1)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\" morerows=\"1\" rowspan=\"2\"\u003e\u003cp\u003e0.523\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\" morerows=\"1\" rowspan=\"2\"\u003e\u003cp\u003e0.324\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eDuring pregnancy\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e44(95.7)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e127(92.0)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e171(92.9)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eNYHA cardiac function classification, n (%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eI-II\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e36(78.3)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e96(69.6)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e132(71.7)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\" morerows=\"1\" rowspan=\"2\"\u003e\u003cp\u003e1.287\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\" morerows=\"1\" rowspan=\"2\"\u003e\u003cp\u003e0.257\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eIII-IV\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e10(21.7)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e42(30.4)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e52(28.3)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003esPAP, Median(mmHg) (M\u0026thinsp;\u0026plusmn;\u0026thinsp;SD)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e50.12\u0026thinsp;\u0026plusmn;\u0026thinsp;23.306\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e58.04\u0026thinsp;\u0026plusmn;\u0026thinsp;21.615\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e56.17\u0026thinsp;\u0026plusmn;\u0026thinsp;22.216\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e-2.666\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e\u003cb\u003e0.008\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003ePAH Grading\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eMild PAH\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e31(67.4)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e54(39.1)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e85(46.2)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\" morerows=\"1\" rowspan=\"2\"\u003e\u003cp\u003e12.267\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\" morerows=\"1\" rowspan=\"2\"\u003e\u003cp\u003e\u003cb\u003e0.002\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eModerate PAH\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e9(19.6)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e64(46.4)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e73(39.7)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eSevere PAH\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e6(13.0)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e20(14.5)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e26(14.1)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eRegular obstetric examinations\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eNO\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e6(13.0)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e15(10.9)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e21(11.4)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e0.161\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e0.688\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eYES\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e40(87.0)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e123(89.1)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e163(88.6)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e\u003cp\u003esPAP, systolic pulmonary artery pressure values in mmHg;\u003c/p\u003e\u003c/div\u003e\u003cdiv id=\"Sec7\" class=\"Section2\"\u003e\u003ch2\u003e3.2 Maternal and fetal/neonatal outcomes\u003c/h2\u003e\u003cp\u003eMaternal outcomes\u003c/p\u003e\u003cp\u003eThe in-hospital outcomes for pregnant women with PAH are summarized in Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e. The median gestational age at delivery was 228.15 days (interquartile range: \u0026plusmn;49.449 days), whereas the mean gestational duration was significantly greater in patients with idiopathic pulmonary arterial hypertension (iPAH) (241.02\u0026thinsp;\u0026plusmn;\u0026thinsp;42.606 days) than in secondary PAH controls (223.86\u0026thinsp;\u0026plusmn;\u0026thinsp;50.95 days). When women with iPAH were compared with those with secondary PAH, the former group experienced significantly higher rates of heart failure (15.2% compared with 4.3%, \u003cem\u003ep\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.013). Among the patients, 152 (99.3%) underwent CS, with 45 (29.6%) undergoing emergency procedures; only 1 woman (0.7%) delivered vaginally.\u003c/p\u003e\u003cp\u003eIn this study, a total of 182 patients (98.9%) survived, while 2 patients (1.1%) died. Notably, there were no fatalities during pregnancy; both women died during the postpartum period. Neither of these patients had been diagnosed with pulmonary hypertension before pregnancy; both received diagnoses of iPAH during their hospitalization. Notably, these two patients were critically ill, had been transferred from other hospitals, and did not receive regular prenatal care throughout their pregnancies. Despite being provided with intensive medical support, their conditions worsened due to multiple organ dysfunction syndrome complicated by a PAH crisis, ultimately resulting in their deaths. Further detailed maternal outcomes can be found in Table\u0026nbsp;\u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e3\u003c/span\u003e.\u003c/p\u003e\u003cp\u003e\u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab3\" border=\"1\"\u003e\u003ccaption language=\"En\"\u003e\u003cdiv class=\"CaptionNumber\"\u003eTable 3\u003c/div\u003e\u003cdiv class=\"CaptionContent\"\u003e\u003cp\u003eMaternal outcomes\u003c/p\u003e\u003c/div\u003e\u003c/caption\u003e\u003ccolgroup cols=\"6\"\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/th\u003e\u003cth align=\"left\" colname=\"c2\"\u003e\u003cp\u003eiPAH\u003c/p\u003e\u003cp\u003en\u0026thinsp;=\u0026thinsp;46(%)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c3\"\u003e\u003cp\u003esecondary PAH n\u0026thinsp;=\u0026thinsp;138(%)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c4\"\u003e\u003cp\u003eAll\u003c/p\u003e\u003cp\u003en\u0026thinsp;=\u0026thinsp;184\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c5\"\u003e\u003cp\u003e\u003cem\u003et/z/χ\u003c/em\u003e\u003csup\u003e2\u003c/sup\u003e\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c6\"\u003e\u003cp\u003e\u003cem\u003eP\u003c/em\u003e\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eDelivery, median days of pregnancy (M\u0026thinsp;\u0026plusmn;\u0026thinsp;SD)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e241.02\u0026thinsp;\u0026plusmn;\u0026thinsp;42.606\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e223.86\u0026thinsp;\u0026plusmn;\u0026thinsp;50.95\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e228.15\u0026thinsp;\u0026plusmn;\u0026thinsp;49.449\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e-2.882\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e\u003cb\u003e0.004\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eMode of delivery #\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003ecesarean section\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e40(97.6)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e112(100.0)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e152(99.3)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e2.75\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e0.268\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003evaginal delivery\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e1(2.4)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e0(0)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e1(0.7)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003ePostpartum hemorrhage\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eNo\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e43(93.5)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e135(97.8)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e178(96.7)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e2.067\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e0.166\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eYes\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e3(6.5)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e3(2.2)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e6(3.3)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eHeart failure\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eNO\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e39(84.8)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e132(95.7)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e171(92.9)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e6.208\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e\u003cb\u003e0.013\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eYES\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e7(15.2)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e6(4.3)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e13(7.1)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eDeath\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eNO\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e44(95.7)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e138(100)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e182(98.9)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e6.066\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e0.061\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eYES\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e2(4.3)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e0(0)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e2(1.1)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e\u003cp\u003e#: 153 completed pregnancies.\u003c/p\u003e\u003cp\u003eFetal/neonatal outcomes\u003c/p\u003e\u003cp\u003eAmong 184 patients, 31 had therapeutic abortions, and 153 had live births. According to the severity of their conditions, among the 31 patients with iatrogenic abortion, 16 were subjected to CS abortions, and 15 received artificial abortions. Among the 153 newborns, 81 (52.9%) were preterm infants. Additionally, 75 infants (49%) had LBW, and 49 (32%) of the neonates were admitted to the NICU. Unfortunately, five neonates (3.1%) died within the first week after birth.\u003c/p\u003e\u003cp\u003eThe study compared fetal outcomes between the secondary PAH and iPAH groups and revealed significant differences in preterm birth and low birth weight (\u003cem\u003ep\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.05). However, there were no significant differences in NICU admissions, neonatal asphyxia, or neonatal deaths (within the first week) between the two groups (\u003cem\u003ep\u003c/em\u003e\u0026thinsp;\u0026gt;\u0026thinsp;0.05). Further detailed maternal and fetal/neonatal outcomes can be found in Table\u0026nbsp;\u003cspan refid=\"Tab4\" class=\"InternalRef\"\u003e4\u003c/span\u003e.\u003c/p\u003e\u003cp\u003e\u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab4\" border=\"1\"\u003e\u003ccaption language=\"En\"\u003e\u003cdiv class=\"CaptionNumber\"\u003eTable 4\u003c/div\u003e\u003cdiv class=\"CaptionContent\"\u003e\u003cp\u003eFetal/neonatal outcomes\u003c/p\u003e\u003c/div\u003e\u003c/caption\u003e\u003ccolgroup cols=\"6\"\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/th\u003e\u003cth align=\"left\" colname=\"c2\"\u003e\u003cp\u003eiPAH\u003c/p\u003e\u003cp\u003en\u0026thinsp;=\u0026thinsp;46(%)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c3\"\u003e\u003cp\u003esecondary PAH n\u0026thinsp;=\u0026thinsp;138(%)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c4\"\u003e\u003cp\u003eAll\u003c/p\u003e\u003cp\u003en\u0026thinsp;=\u0026thinsp;184\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c5\"\u003e\u003cp\u003e\u003cem\u003eχ\u003c/em\u003e\u003csup\u003e2\u003c/sup\u003e\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c6\"\u003e\u003cp\u003e\u003cem\u003eP\u003c/em\u003e\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003ePremature infants (\u0026lt;\u0026thinsp;37 weeks)#\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eNo\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e27(65.9)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e45(40.2)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e72(47.1)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e7.941\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e\u003cb\u003e0.005\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eYes\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e14(34.1)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e67(59.8)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e81(52.9)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eAdmission to NICU#\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eNo\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e30(73.2)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e74(66.1)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e104(68.0)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e0.695\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e0.405\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eYes\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e11(26.8)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e38(33.9)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e49(32.0)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eLow birth weight (\u0026lt;\u0026thinsp;2500 g)#\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eNo\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e27(65.9)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e51(45.5)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e78(51.0)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e4.958\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e\u003cb\u003e0.026\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eYes\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e14(34.1)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e61(54.5)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e75(49.0)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eNeonatal asphyxia#\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eNo\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e40(97.6)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e103(92.0)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e143(93.5)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e1.539\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e0.29\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eYes\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e1(2.4)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e9(8.0)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e10(6.5)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eNeonatal death(\u0026lt;\u0026thinsp;1 week)#\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eNo\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e39(95.1)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e119(97.5)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e158(96.9)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e0.604\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e0.6\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eYes\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e2(4.9)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e3(2.5)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e5(3.1)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eFetal outcome\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eLive birth\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e41(89.1)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e112(81.2)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e153 (83.2)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e1.565\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e0.211\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eAbortion\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e5(10.9)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e26(18.8)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e31 (16.8)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e\u003cp\u003e#: Fetal/neonatal outcomes in the 153 completed pregnancies. NICU: Neonatal intensive care unit\u003c/p\u003e\u003c/div\u003e\u003cdiv id=\"Sec8\" class=\"Section2\"\u003e\u003ch2\u003e3.3 Management of pregnant women with PAH\u003c/h2\u003e\u003cp\u003eIn this study, CS was the primary mode of childbirth for pregnant women with PAH. Among the patients who underwent cesarean termination, only 12 (7.2%) received general anesthesia, whereas 154 (92.8%) were administered spinal anesthesia. The comparative analysis revealed no significant differences between the two anesthesia groups.\u003c/p\u003e\u003cp\u003eThe average operative time for CS was 48.92\u0026thinsp;\u0026plusmn;\u0026thinsp;19.756 minutes. Notably, the iPAH group had significantly longer operation times than did the secondary PAH group (57.0\u0026thinsp;\u0026plusmn;\u0026thinsp;26.567 minutes vs. 46.18\u0026thinsp;\u0026plusmn;\u0026thinsp;16.07 minutes, \u003cem\u003ep\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.001). Additionally, there were significant differences in intraoperative blood loss, with the iPAH group exhibiting a substantially greater hemorrhage volume (539.29\u0026thinsp;\u0026plusmn;\u0026thinsp;348.084 mL vs. 388.307\u0026thinsp;\u0026plusmn;\u0026thinsp;197.013 mL, \u003cem\u003ep\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.001).\u003c/p\u003e\u003cp\u003eGiven the limited use of uterine contraction agents in patients with PAH, achieving effective hemostasis during cesarean delivery is essential for preventing PPH. In the iPAH group, a larger proportion of patients (83.3% vs. 64.5%) utilized additional surgical techniques to minimize bleeding, such as ligation of the upper uterine arteries, uterine bundling, and the B-Lynch suture technique. As a result of these interventions, the incidence of PPH was only 3.3% (six patients).\u003c/p\u003e\u003cp\u003eIn this study, we used low-dose oxytocin to prevent PPH (10 U of oxytocin in 500 mL of normal saline given intravenously at 36 mL/hour for 4 hours (12 mU/min)). In total, 82.5% (137 patients) of the patients received oxytocin infusion during surgery to prevent hemorrhage. Furthermore, 86.4% (159 patients) initiated anticoagulation therapy on the first postoperative day. No significant differences were found between the two groups regarding intraoperative oxytocin use, anticoagulation therapy, ICU admission rates, or breastfeeding status. The detailed data can be found in Table\u0026nbsp;\u003cspan refid=\"Tab5\" class=\"InternalRef\"\u003e5\u003c/span\u003e.\u003c/p\u003e\u003cp\u003e\u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab5\" border=\"1\"\u003e\u003ccaption language=\"En\"\u003e\u003cdiv class=\"CaptionNumber\"\u003eTable 5\u003c/div\u003e\u003cdiv class=\"CaptionContent\"\u003e\u003cp\u003eManagement of pregnant women with PAH\u003c/p\u003e\u003c/div\u003e\u003c/caption\u003e\u003ccolgroup cols=\"6\"\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/th\u003e\u003cth align=\"left\" colname=\"c2\"\u003e\u003cp\u003eiPAH\u003c/p\u003e\u003cp\u003en\u0026thinsp;=\u0026thinsp;46(%)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c3\"\u003e\u003cp\u003esecondary PAH n\u0026thinsp;=\u0026thinsp;138(%)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c4\"\u003e\u003cp\u003eAll\u003c/p\u003e\u003cp\u003en\u0026thinsp;=\u0026thinsp;184\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c5\"\u003e\u003cp\u003e\u003cem\u003et/z/χ\u003c/em\u003e\u003csup\u003e2\u003c/sup\u003e\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c6\"\u003e\u003cp\u003e\u003cem\u003eP\u003c/em\u003e\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eWay of anesthesia #\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e1.97\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e0.299\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eSpinal anesthesia\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e41(97.6)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e113(91.1)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e154(92.8)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eGeneral anesthesia\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e1(2.4)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e11(8.9)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e12(7.2)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eSurgery time(minutes)(M\u0026thinsp;\u0026plusmn;\u0026thinsp;SD)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e57.0\u0026thinsp;\u0026plusmn;\u0026thinsp;26.567\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e46.18\u0026thinsp;\u0026plusmn;\u0026thinsp;16.075\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e48.92\u0026thinsp;\u0026plusmn;\u0026thinsp;19.756\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e-3.378\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e\u003cb\u003e0.001\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eBlood loss during CS(ml)(M\u0026thinsp;\u0026plusmn;\u0026thinsp;SD)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e539.29\u0026thinsp;\u0026plusmn;\u0026thinsp;348.084\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e388.307\u0026thinsp;\u0026plusmn;\u0026thinsp;197.013\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e426.506\u0026thinsp;\u0026plusmn;\u0026thinsp;251.745\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e-3.883\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e\u003cb\u003e\u0026lt;\u0026thinsp;0.001\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eSuturing techniques during CS #\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eNO\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e7(16.7)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e44(35.5)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e51(30.7)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e5.219\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e\u003cb\u003e0.022\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eYES\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e35(83.3)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e80(64.5)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e115(69.3)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eOxytocin use during CS #\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eNO\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e8(19.0)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e21(16.9)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e29(17.5)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e0.097\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e0.755\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eYES\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e34(81.0)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e103(83.1)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e137(82.5)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eAntithrombotic therapy\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eNO\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e10(21.7)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e15(10.9)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e25(13.6)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e3.472\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e0.062\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eYes\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e36(78.3)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e123(89.1)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e159(86.4)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eAdmission to ICU\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eNO\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e17(37.0)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e36(26.1)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e53(28.8)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e21.988\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e0.159\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eYES\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e29(63.0)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e102(73.9)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e131(71.2)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eBreastfeeding\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eNO\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e35(76.1)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e101(73.2)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e136(73.9)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e0.15\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e0.698\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eYES\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e11(23.9)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e37(26.8)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e48(26.1)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003ctfoot\u003e\u003ctr\u003e\u003ctd colspan=\"6\"\u003e#:168 patients who underwent CS\u003c/td\u003e\u003c/tr\u003e\u003c/tfoot\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e\u003cp\u003ePulmonary Vasodilators\u003c/p\u003e\u003cp\u003eIn total, among these pregnancies, 11 (6.0%) were treated with PAH-targeted therapy: 2 (1.1%) received a combination of treprostinil and sildenafil before the pregnancy operation, while 9 (4.9%) were given pulmonary vasodilators before the operation\u0026mdash;2 received treprostinil alone, and 7 were given treprostinil along with sildenafil.\u003c/p\u003e\u003c/div\u003e"},{"header":"Discussion","content":"\u003cp\u003eThis retrospective cohort study analyzed 184 PAH-complicated pregnancies (46 iPAH pregnancies vs. 138 secondary PAH pregnancies) to delineate differential management strategies and maternal-fetal outcomes. The prevalence of PAH has risen markedly in recent decades, imposing a substantial societal disease burden \u003csup\u003e\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e\u003c/sup\u003e. Pregnancy exacerbates the disease burden associated with PAH, with a perinatal mortality rate as high as 3.3% \u003csup\u003e6\u003c/sup\u003e. IPAHs and secondary PAHs differ in their pathogenesis and clinical presentation \u003csup\u003e\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e\u003c/sup\u003e. Studies have shown a significant increase in the incidence of idiopathic pulmonary arterial hypertension (iPAH) during pregnancy, increasing from 3.3\u0026ndash;25.6% to 59.6% \u003csup\u003e6,7,13,18\u003c/sup\u003e. The mortality rate for pregnant women with iPAH can reach 50%, which is far higher than that for those with secondary PAH \u003csup\u003e\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e\u003c/sup\u003e. The increasing incidence of iPAH during pregnancy underscores the necessity for tailored management strategies across PAH subtypes.\u003c/p\u003e\u003cp\u003e\u003cb\u003eClinical feature variations\u003c/b\u003e\u003c/p\u003e\u003cp\u003eIn this study, the average age of patients in the iPAH group was 31.35 years (\u0026plusmn;\u0026thinsp;4.498), which was significantly greater than that of patients in the secondary PAH group at 28.93 years (\u0026plusmn;\u0026thinsp;4.875, \u003cem\u003ep\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.003). Additionally, the average BMI of the iPAH group was 26.048 kg/m\u003csup\u003e2\u003c/sup\u003e (\u0026plusmn;\u0026thinsp;3.594), which was also significantly greater than that of the secondary PAH group (24.15 kg/m\u003csup\u003e2\u003c/sup\u003e) (\u0026plusmn;\u0026thinsp;3.787, \u003cem\u003ep\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.003). These findings suggest that advanced age and obesity may be independent risk factors for iPAH patients. This conclusion is consistent with the research results of Wahab et al. \u003csup\u003e19\u003c/sup\u003e, who noted that obesity-related cardiopulmonary diseases can significantly increase the risk of PAH. Obesity may lead to endothelial dysfunction and inflammatory responses, thereby exacerbating the pathophysiological process of PAH \u003csup\u003e\u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e\u003c/sup\u003e. Moreover, advanced age itself may also be associated with degenerative changes in the cardiovascular system, further increasing the risk of developing PAH \u003csup\u003e\u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e,\u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e\u003c/sup\u003e.\u003c/p\u003e\u003cp\u003eNotably, in the iPAH group, 92.9% of the patients were first diagnosed during pregnancy, indicating strong concealment of iPAH. In contrast, the majority of cases in the secondary PAH group were related to congenital heart disease (CHD-PAH, accounting for 60.9%), and these patients often have a clear cardiovascular disease foundation before pregnancy \u003csup\u003e\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e,\u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e23\u003c/span\u003e,\u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e24\u003c/span\u003e\u003c/sup\u003e. The concealment of iPAH means that patients diagnosed during pregnancy face greater risks because the condition may have already progressed to a more severe stage at this time. Therefore, for high-risk groups, especially women of advanced age and with high BMIs, increasing the frequency of prenatal screening is particularly important. By increasing the frequency of examinations such as echocardiography, potential PAH patients can be identified earlier, allowing timely intervention and management to reduce the risk of adverse outcomes for both mothers and fetuses.\u003c/p\u003e\u003cp\u003eComparison of perioperative management strategies\u003c/p\u003e\u003cp\u003eIn this study, both the iPAH and secondary PAH groups presented a high CS rate (99.3%). However, the iPAH group had a significantly longer surgical time (57.0\u0026thinsp;\u0026plusmn;\u0026thinsp;26.567 minutes vs. 46.18\u0026thinsp;\u0026plusmn;\u0026thinsp;16.07 minutes, \u003cem\u003ep\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.001) and greater intraoperative blood loss (539.29\u0026thinsp;\u0026plusmn;\u0026thinsp;348.084 mL vs. 388.307\u0026thinsp;\u0026plusmn;\u0026thinsp;197.013 mL, \u003cem\u003ep\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.001). These differences may be due to the greater vulnerability of right heart function to volume load fluctuations in iPAH patients, which requires more precise hemodynamic management during surgery. To address the increased risk of bleeding, the iPAH group more frequently employed prophylactic hemostatic techniques (83.3% vs. 64.5%, \u003cem\u003ep\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.022), such as uterine artery ligation and B-Lynch suturing. Current guidelines recommend prophylactic hemostatic measures for high-risk PPH patients \u003csup\u003e\u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e25\u003c/span\u003e,\u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e26\u003c/span\u003e\u003c/sup\u003e. This proactive approach contributes to a lower PPH rate of 3.3% in the iPAH group, which is better than the 10%-15% reduction reported in previous studies.\u003c/p\u003e\u003cp\u003eIn this study, both groups predominantly utilized neuraxial anesthesia (92.8%), reflecting its widespread application in cesarean deliveries for PAH patients. This preference stems from the ability of neuraxial anesthesia to provide stable hemodynamic control and reduce the risk of intraoperative and postoperative complications. However, despite the similarity in anesthesia methods, a significant difference was observed in the postoperative use of oxytocin between the two groups.\u003c/p\u003e\u003cp\u003eNonetheless, our study validated the safety of low-dose oxytocin (12 mU/min) as a preventive strategy against postpartum hemorrhage in PAH patients. Compared with the secondary PAH group, the iPAH group had a significantly lower rate of oxytocin use (81.0% vs. 83.1%, \u003cem\u003ep\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.755). The results indicated no statistically significant difference in PPH risk between the two groups when low-dose oxytocin was combined with prophylactic hemostatic techniques (6.5% vs. 2.2%, \u003cem\u003ep\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.166). The use of oxytocin in PAH patients remains a contentious clinical dilemma \u003csup\u003e\u003cspan citationid=\"CR27\" class=\"CitationRef\"\u003e27\u003c/span\u003e\u003c/sup\u003e. Oxytocin may exacerbate pulmonary hypertension through dual mechanisms: pulmonary vasoconstriction elevates pulmonary artery pressure, and systemic vasodilation reduces right ventricular preload, potentially precipitating right heart failure \u003csup\u003e\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e\u003c/sup\u003e. Zhang et al. reported that the use of oxytocin in iPAH patients was associated with a significant increase in sPAP, leading to the discontinuation of oxytocin use. However, it should be noted that the subjects included in that study were all patients with severe iPAH, and the dose of oxytocin used was 10 U. However, Shu et al.\u003csup\u003e28\u003c/sup\u003e reported that the use of oxytocin in PAH patients is safe. The use of low-dose oxytocin (12 mU/min) in PAH patients can effectively prevent PPH, with no adverse outcomes, such as heart failure, occurring \u003csup\u003e\u003cspan citationid=\"CR29\" class=\"CitationRef\"\u003e29\u003c/span\u003e,\u003cspan citationid=\"CR30\" class=\"CitationRef\"\u003e30\u003c/span\u003e\u003c/sup\u003e.\u003c/p\u003e\u003cp\u003e The relevant guidelines do not explicitly prohibit the use of oxytocin in PAH patients but emphasize the risk of right ventricular failure and a low-output state. The combination of low-dose oxytocin infusion and prophylactic surgical hemostatic measures is effective in reducing the risk of bleeding after cesarean section. However, its use should be carefully considered on the basis of the individual patient's condition.\u003c/p\u003e\u003cp\u003eMaternal outcomes\u003c/p\u003e\u003cp\u003eIn our study, the iPAH group presented a 3.5-fold greater incidence of heart failure (15.2% vs. 4.3%, p\u0026thinsp;=\u0026thinsp;0.013), and mortality was concentrated in the severe PAH subgroup (4.3% vs. 0%), driven by irreversible pulmonary vascular remodeling and right ventricular decompensation exacerbated by pregnancy-induced volume overload. In contrast, secondary PAH patients demonstrated hemodynamic reversibility through preconception shunt correction, enhancing cardiac reserve and reducing acute failure risk. Mortality rates across studies show a downward trend (0.51% in large cohorts vs. 17.6% in Zhang et al.) \u003csup\u003e1,2\u003c/sup\u003e, with our study reporting 1.1% mortality, attributed to early detection and improved management. Liu et al.'s study further revealed that iPAH has a mortality rate of 33.3%, which significantly exceeds that reported for secondary PAH subtypes. However, in both their study and the present research, all deceased patients had severe PAH. These findings underscore that iPAH patients\u0026rsquo; right ventricles exhibit extreme sensitivity to volume loading, necessitating stricter peripartum hemodynamic monitoring. Severe PAH confers prohibitive maternal risk, which warrants prepregnancy counseling for avoidance or termination \u003csup\u003e\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e,\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e,\u003cspan citationid=\"CR31\" class=\"CitationRef\"\u003e31\u003c/span\u003e\u003c/sup\u003e.\u003c/p\u003e\u003cp\u003eFetal/neonatal outcomes\u003c/p\u003e\u003cp\u003eAdditionally, patients with PAH are at increased risk for adverse fetal outcomes. Sliwa et al. \u003csup\u003e6\u003c/sup\u003e reported that the neonatal mortality rate was 9.3% within the first week of life, and 20% of neonates born to patients with PAH were small for gestational age, with 4% having some form of cardiac anomaly. In our study, 31 patients underwent medically indicated abortions because they were unsuitable for pregnancy. Among the 153 live births, 81 (52.9%) were preterm infants, with a greater proportion observed in the secondary PAH group. This may be related to guidelines recommending pregnancy termination at 32\u0026ndash;34 weeks for severe heart disease \u003csup\u003e\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e,\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e\u003c/sup\u003e. Therefore, the greater proportion of preterm infants in the secondary PAH group may be related to the results of this study. Planned CS ensures maternal and fetal safety, with no maternal deaths in the secondary PAH group. Close antenatal monitoring likely contributed to the low neonatal asphyxia and mortality rates, which were lower than those reported in the literature.\u003c/p\u003e\u003cp\u003eLimitations\u003c/p\u003e\u003cp\u003eThis study, as a single-center retrospective analysis with diagnoses primarily based on echocardiography, may underestimate the severity of PAH \u003csup\u003e\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e\u003c/sup\u003e. Additionally, the lack of long-term follow-up data limits the evaluation of neonates' extended prognoses. Future investigations should adopt multicenter prospective designs incorporating right heart catheterization and genetic profiling (including \u003cem\u003eBMPR2\u003c/em\u003e mutation screening) to classify PAH subtypes precisely and establish phenotype-specific management protocols.\u003c/p\u003e"},{"header":"Conclusion","content":"\u003cp\u003eManagement of iPAH and secondary PAH pregnancies demands subtype-tailored approaches. For iPAH, the clinical focus should focus on early screening in advanced-age or obese populations, intraoperative hemostatic precision, and optimized dosing of targeted pulmonary vasodilators. In contrast, secondary PAH management requires prioritization of primary disease control (e.g., congenital heart defect repair) and risk-stratified pregnancy termination timing. Low-dose oxytocin combined with prophylactic surgical hemostasis is safe for both subtypes but necessitates rigorous individualized risk‒benefit analysis. Crucially, MDT coordination remains pivotal for improving maternal\u0026ndash;fetal outcomes.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003eFunding: This study was supported by the National Key R\u0026amp;D Program of China (grant number 2022YFC2704103) and the National Key Research and Development Program of China (2021YFC2701501). This work was not associated with any commercial entity.\u003c/p\u003e\n\u003cp\u003eEthics approval and consent to participate\u003c/p\u003e\n\u003cp\u003eThis study was approved by the Ethics Committee of West China Second University Hospital of Sichuan University (No. 2025188) and conducted according to ICMJE recommendations.\u003c/p\u003e\n\u003cp\u003eConsent for publication\u003c/p\u003e\n\u003cp\u003eAll participants provided informed consent.\u003c/p\u003e\n\u003cp\u003eAvailability of data and materials\u003c/p\u003e\n\u003cp\u003eOwing to privacy and ethical concerns, the data cannot be made publicly available. However, these data are available from the corresponding author upon reasonable request.\u003c/p\u003e\n\u003cp\u003eCompeting interests\u003c/p\u003e\n\u003cp\u003eThe authors declare\u0026nbsp;that they have no competing interests.\u003c/p\u003e\n\u003cp\u003eFunding\u003c/p\u003e\n\u003cp\u003eNo funding\u003c/p\u003e\n\u003cp\u003eAuthors\u0026apos; contributions\u003c/p\u003e\n\u003cp\u003eAll the authors contributed to and participated in the preparation of the manuscript and research steps in the present study as follows: Conception and design of the research\u0026mdash;Lu Jiang, Fan Yang, Yueheng Peng, Ying Zheng and Guolin He ; acquisition of data collection and statistical analysis\u0026mdash;Lu Jiang and Yiheng Tian; writing of original draft\u0026mdash;Lu Jiang ; Reading, Revising and Final approval for submission\u0026mdash;All.\u003c/p\u003e\n\u003cp\u003eAcknowledgment\u003c/p\u003e\n\u003cp\u003eThe authors thank all the participants of this study.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eAgrawal A, Bajaj S, Bhagat U, Yesilyaprak A, Chandna S, Arockiam AD, Jamil Y, El Iskandarani M, Gupta R, Majid M, Nayar D, Michos ED. 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A case series describing the multidisciplinary management of pulmonary arterial hypertension in pregnancy: Time for optimism. \u003cem\u003eAust N Z J Obstet Gynecol\u003c/em\u003e 2023;\u003cstrong\u003e63\u003c/strong\u003e:66\u0026ndash;73.\u003c/li\u003e\n\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"bmc-pregnancy-and-childbirth","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"prch","sideBox":"Learn more about [BMC Pregnancy and Childbirth](http://bmcpregnancychildbirth.biomedcentral.com/)","snPcode":"","submissionUrl":"https://www.editorialmanager.com/prch/default.aspx","title":"BMC Pregnancy and Childbirth","twitterHandle":"@BMC_series","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"em","reportingPortfolio":"BMC Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true},"keywords":"Pulmonary arterial hypertension, secondary pulmonary arterial hypertension, idiopathic pulmonary arterial hypertension, perinatal outcomes","lastPublishedDoi":"10.21203/rs.3.rs-7513096/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-7513096/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eObjective: To compare the clinical characteristics, peripartum management, and maternal and fetal outcomes between pregnant women with idiopathic pulmonary arterial hypertension (iPAH) and those with secondary pulmonary arterial hypertension.\u003c/p\u003e\n\u003cp\u003eMethods: This was a retrospective cohort study. A total of 184 pregnant patients with PAH were admitted to West China Second University Hospital from 2014–2024. Patients were divided into iPAH (n=46) and secondary PAH (n=138) groups\u003cu\u003e \u003c/u\u003eon the basis of the etiology of PAH. Demographic and clinical data extracted from medical records included maternal demographics, clinical characteristics, mode of delivery, anesthesia methods, postpartum complications, and fetal/neonatal outcomes.\u003c/p\u003e\n\u003cp\u003eResults: The median maternal age was 29.54 years, with 25% iPAH cases and 75% secondaryPAH cases. The majority (92.9%) were diagnosed during pregnancy. Compared with secondary PAH patients,\u003cu\u003e \u003c/u\u003eiPAH patients had a greater average age (31.35 vs. 28.93 years,\u003cem\u003e p\u003c/em\u003e=0.003) and BMI (26.05 vs. 24.15 kg/m\u003csup\u003e2\u003c/sup\u003e, \u003cem\u003ep\u003c/em\u003e=0.003) but lower systolic pulmonary artery pressure (sPAP) (50.12 vs. 58.04 mmHg,\u003cem\u003e p\u003c/em\u003e=0.008). Cesarean section was the predominant delivery method (99.3%), with 97.6% of iPAH patients and 91.1% of secondary PAH patients receiving spinal anesthesia. Intraoperative blood loss was greater in the iPAH group (539.29 vs. 388.31 mL, \u003cem\u003ep\u003c/em\u003e\u0026lt;0.001). The overall in-hospital survival rate was 98.9%, with a maternal mortality rate of 1.1%. The fetal outcomes included a preterm birth rate of 52.9% and low birth weight in 49% of the neonates. No significant differences in neonatal outcomes were detected between the\u003cu\u003e \u003c/u\u003eiPAH and secondary PAH groups.\u003c/p\u003e\n\u003cp\u003eConclusion: Despite multidisciplinary management improving survival, iPAH pregnancies are associated with increased maternal mortality and heart failure risks. Cesarean delivery with tailored hemostasis and cautious oxytocin use optimizes outcomes. Early prenatal screening, especially in high-risk women (advanced age, obesity), and phenotype-specific protocols are critical to mitigate risks. The limitations of this study include its retrospective design and echocardiography-based PAH diagnosis.\u003c/p\u003e","manuscriptTitle":"Comparison of Perinatal Outcomes and Delivery Strategies in Pregnant Women with Idiopathic vs. Secondary Pulmonary Arterial Hypertension: A Retrospective Cohort Study","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-11-11 16:15:27","doi":"10.21203/rs.3.rs-7513096/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"reviewerAgreed","content":"146963655055584884947580493305632356747","date":"2025-11-08T16:43:54+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-11-02T21:25:59+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"274125960259555372796876585031044995966","date":"2025-10-30T16:23:44+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2025-10-30T12:59:50+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2025-10-28T09:53:49+00:00","index":"","fulltext":""},{"type":"editorInvited","content":"","date":"2025-10-08T10:47:04+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2025-10-08T01:03:24+00:00","index":"","fulltext":""},{"type":"submitted","content":"BMC Pregnancy and Childbirth","date":"2025-10-08T01:00:16+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"bmc-pregnancy-and-childbirth","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"prch","sideBox":"Learn more about [BMC Pregnancy and Childbirth](http://bmcpregnancychildbirth.biomedcentral.com/)","snPcode":"","submissionUrl":"https://www.editorialmanager.com/prch/default.aspx","title":"BMC Pregnancy and Childbirth","twitterHandle":"@BMC_series","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"em","reportingPortfolio":"BMC Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"71250ee8-baab-4a16-af86-87055b3baaa7","owner":[],"postedDate":"November 11th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"under-review","subjectAreas":[],"tags":[],"updatedAt":"2025-11-11T16:15:27+00:00","versionOfRecord":[],"versionCreatedAt":"2025-11-11 16:15:27","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-7513096","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-7513096","identity":"rs-7513096","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}