A diagnostic challenge: spontaneous hemoperitoneum in pregnancy versus uterine rupture

The differential diagnosis of pain and sonographic findings of intra-abdominal effusion during pre - gnancy or in the hours immediately following birth is complex and requires careful considera - tion of various potential causes. Uterine rupture [1], a life-threatening obstetric emergency, must

Background. Spontaneous hemoperitoneum in pregnancy (SHiP) is a rare but life-threatening complication. SHiP typically presents with abdominal pain, hypovolemia, and decreased haemoglobin in later pregnancy. Case presentation. A 38-year-old woman with a history of one prior caesare- an section, and otherwise in good health, presented at 29 weeks of gestation with sudden onset of abdominal pain. Ultrasound revealed free fluid in her abdomen, raising concern for uterine rupture due to the previous caesarean section. However, a dedicated ultrasound examination ruled this out. Lapa- roscopy confirmed the absence of uterine involvement. The lower uterine segment was intact and was not the source of bleeding; indeed, the source of bleeding was identified as a 2-cm clot in the left fallopian tube resulting on histology an endometriosis foci. Conclusions. This case highlights the importance of considering SHiP in the differential diagnosis of acute abdomen during pregnancy, even in the absen- ce of known risk factors because a high index of suspicion for SHiP is crucial for prompt diagnosis and intervention, aiming for optimal maternal and feta outcomes. be promptly excluded. However, other conditions such as spontaneous hemoperitoneum in pregnan- cy (SHIP), bladder rupture [2], and ascites [3] can present with similar clinical features. A thorough evaluation, including imaging studies, laboratory tests, and clinical assessment, is essential to diffe - rentiate between these conditions and ensure ap - propriate management. 413 SHiP vs uterine rupture Stefano Restaino, Ginevra Battello, Sara Olivola, et al. In particular, spontaneous hemoperitoneum in pregnancy (SHiP) is defined as a sudden non-trau- matic intraperitoneal bleeding in pregnancy and up to 42 days postpartum [4]. SHiP typically pre - sents during the latter stages of pregnancy, accom- panied by a combination of abdominal pain, signs of hypovolemia, a decrease in haemoglobin levels, and foetal distress. This condition carries a signifi- cant risk of maternal and perinatal mortality and morbidity [5]. Due to the absence of comprehen - sive global surveillance, estimating the exact in - cidence of SHiP remains challenging. However, a study conducted by the Italian Obstetric Sur - veillance System (ItOSS) between 2013 and 2017 documented seven maternal deaths attributed to SHiP and calculated a specific maternal mortality rate (MMR) of 0.2 cases per 100,000 live births [6]. While the precise aetiology of SHiP remains un - clear, advanced maternal age, endometriosis [7], multiple pregnancies and assisted reproductive technologies (ART) have been suggested as po - tential risk factors [8, 9]. The case we are about to present is unique in its kind, as it is a case of spontaneous hemoperito - neum in pregnancy in a patient with previous cae- sarean section. This case underlines the importance of making a correct differential diagnosis, because in a pregnant patient with previous uterine sur - gery, the onset of abdominal pain and the presence of intra-abdominal fluid do not necessarily mean uterine rupture. CASE PRESENTATION We present the case of a 38-year-old woman, G3P1, with a previous obstetric history of a full-term ca- esarean section for arrested labour, pregnant at 29 weeks of gestation with a sudden onset of acute abdominal pain. Ultrasound performed upon admission showed a moderate amount of free fluid collection in both the hepatic and splenic recesses, extending into the pelvis. At the level of the lower uterine segment, in the site of a previous caesarean section scar, there are no apparent signs of dehiscence or rupture of the uterine wall. Blood tests revealed a haemoglo- bin level of 9.2 g/dL. Twelve hours after the previous tests, a blood sam- ple was repeated and attested a sudden drop of the haemoglobin level at 8.3 g/dL. A repeated ultrasound revealed diffuse abdominal free fluid collection, increased in volume compared to the previous imaging documentation, with echogeni - city compatible with a haemorrhagic type of fluid collection. It was decided to administer antenatal corticoste - roid prophylaxis and foetal neuroprotection with magnesium sulphate. Due to persistent acute abdo- minal pain, anaemia with signs of initial hemody- namic instability in a suspected case of hemoperito- neum, an urgent surgical intervention was decided. A diagnostic laparoscopy was performed to inve - stigate intra-abdominal bleeding. Blood clots were found in the parietocolic gutters, hepatic lodge, and splenic lodge and about 1,300 mL of blood in the abdominal cavity was evacuated. No active blee - ding from the upper abdomen seemed to be pre - sent. However, the gravid uterus impeded adequa- te visualization of the lower abdomen, preventing identification of the bleeding source. Therefore, a decision was made to convert to la - parotomy based on the haemodynamic instability of the patient and the confirmed significant he - moperitoneum (> 1,000 cc) found on laparoscopic approach. Upon open exploration, no active up - per abdominal bleeding was confirmed. While the pelvic cavity was thoroughly examined, no signs of uterine rupture or bleeding from previous scar sites were detected. The laparotomic surgical ap - proach allowed for a complete visualization of the pelvis, leading to the identification of the active bleeding focus: a 2-cm firm clot with surrounding inflammation and active bleeding in the middle third of the left fallopian tube. Additionally, a se - condary bleeding site was found on the omentum. Due to the patient’s deteriorating hemodynamic status, an emergency caesarean section was de - cided. A transplacental transverse corporal incision was performed, and a female newborn was extracted. The neonate weighed 1,237 grams and had an AP- GAR score of 1/4/7, umbilical cord pH was 7.30 with a BE of -2.3 mMol/L. The newborn required intubation and ventilation, and surfactant was ad- ministered. The newborn was subsequently extuba- ted at 6 hours of life with a good neonatal outcome. After the caesarean section, a salpingectomy and a partial omentectomy were therefore performed. No other sources of bleeding were evident. The histo- logical results were unexpected, demonstrating foci of endometriosis in the fallopian tube, even though there was no previous medical history suggestive of endometriosis. Ital J Gynaecol Obstet 2025, 37, N.4 414 SHiP vs uterine rupture ly from SHiP to uterine rupture. While with uterine rupture always necessitates a caesarean section, in cases of SHiP , in the presence of maternal hemody- namic stability and after identifying and control - ling the bleeding site, it is possible, in some cases, to continue the pregnancy [12]. COMPLIANCE WITH ETHICAL STANDARDS Authors’ contribution S.R.: Conceptualization. S.O.: Data curation. L.D., G.V .: Supervision. G.B.: Writing – original draft. M.A.: Writing – review & editing. Funding None. Study registration N/A. Disclosure of interests The authors declare that they have no conflict of interests. Ethical approval IRB approval was obtained (RIF. Prot IRB: 42/2024). Informed consent Patient’s consent to publication was obtained. Data sharing N/A.

1. Guiliano M, Closset E, Therby D, LeGoueff F, Deruelle P , Subtil D. Signs, symptoms and com- plications of complete and partial uterine rup- tures during pregnancy and delivery. Eur J Ob- stet Gynecol Reprod Biol. 2014;179:130-4. doi: 10.1016/j.ejogrb.2014.05.004. 2. Stabile G, Cracco F, De Santo D, Zinicola G, Romano F, De Manzini N, et al. Spontaneous Bladder Rupture after Normal Vaginal Deliv- ery: Description of a Rare Complication and Systematic Review of the Literature. Diagnos- tics (Basel). 2021;11(10):1885. doi: 10.3390/diag- nostics11101885. 3. Epelde C, Saravia F, Aguinaga M, Toledo A, Le- kuona A, Gorostidi M. Acute Abdomen in Preg-

Hormonal changes during pregnancy can exert a substantial impact on the endometriotic tissue, in a process termed “decidualization” of ectopic en - dometrium, ultimately increasing the likelihood of bleeding from endometriotic lesions [10]. This phenomenon of decidualization explains why endometriosis is a major risk factor for SHiP . Un- fortunately, endometriosis is still an underdiagno- sed and underestimated condition, as evidenced by the case presented of an incidental diagnosis of endometriosis following a case of spontaneous hemoperitoneum of pregnancy. In our case, the most obvious differential diagnosis was the previous caesarean section scar rupture but that was ruled out by a sonographic evaluation of the lower uterine segment. In our Clinic we routi - nely perform an ultrasound evaluation of the lower uterine segment (LUS) in pregnant women with a history of caesarean delivery. We use state-of-the- art ultrasound equipment and highly trained sono- graphers to perform LUS evaluations. Acquiring a high level of expertise in ultrasound evaluation of the lower uterine segment is essential for optimal maternal and foetal care in pregnant women with a previous caesarean section. Our team has exten- sive experience in interpreting ultrasound images and can identify even subtle abnormalities [11]. The expertise in sonographic LUS evaluation allows to accurately assess the thickness and integrity of the LUS and identify or rule out potential complica - tions such as uterine rupture and dehiscence of a previous caesarean scar.

Spontaneous hemoperitoneum of pregnancy (SHiP) is a critical differential diagnosis in cases of acute abdominal pain during pregnancy. It should be considered especially in women with risk factors like endometriosis or those who have undergone assisted reproductive technologies (ART). Howe - ver, as this case demonstrates, SHiP can occur even in the absence of known risk factors, and therefore, it should always be considered as a possible cause of acute abdominal pain in pregnant women, re - gardless of their medical history, and even if other conditions, like a ruptured caesarean scar, seemed more likely. Early and accurate differential diagnosis is essen - tial, as the therapeutic approach differs significant- 415 SHiP vs uterine rupture Stefano Restaino, Ginevra Battello, Sara Olivola, et al. nancy due to Idiopathic Chylous Ascites. Case Rep Obstet Gynecol. 2024;2024:8898451. doi: 10.1155/2024/8898451. 4. Say L, Souza JP , Pattinson RC; WHO working group on Maternal Mortality and Morbidity classi- fications. Maternal near miss--towards a standard tool for monitoring quality of maternal health care. Best Pract Res Clin Obstet Gynaecol. 2009;23(3):287- 96. doi: 10.1016/j.bpobgyn.2009.01.007. 5. Lier MCI, Malik RF, Ket JCF, Lambalk CB, Bros- ens IA, Mijatovic V . Spontaneous hemoperitone- um in pregnancy (SHiP) and endometriosis - A systematic review of the recent literature. Eur J Obstet Gynecol Reprod Biol. 2017;219:57-65. doi: 10.1016/j.ejogrb.2017.10.012. 6. Donati S, Maraschini A, Dell’Oro S, Lega I, D’Aloja P; Regional Maternal Mortality Work- ing Group. The way to move beyond the num- bers: the lesson learnt from the Italian Obstet- ric Surveillance System. Ann Ist Super Sanita. 2019;55(4):363-70. doi: 10.4415/ANN_19_04_10. 7. Maiorana A, Zaccaria G, Parisi G, Mercurio A, For- lani F. Spontaneous hemoperitoneum in pregnan- cy due to rupture of uterine vessels in woman with endometriosis: a case report. Ital J Gynaecol Ob- stet. 2024;36(2):191-5 doi: 10.36129/jog.2023.124. 8. Brosens IA, Lier MC, Mijatovic V , Habiba M, Benagiano G. Severe spontaneous hemoperito- neum in pregnancy may be linked to in vitro fertilization in patients with endometriosis: a systematic review. Fertil Steril. 2016;106(3):692- 703. doi: 10.1016/j.fertnstert.2016.05.025. 9. Mazzocco MI, Donati S, Maraschini A, Corsi E, Colciago E, Guelfi F, et al. Spontaneous he- moperitoneum in pregnancy: Italian prospec- tive population-based cohort study. Acta Ob- stet Gynecol Scand. 2022;101(11):1220-6. doi: 10.1111/aogs.14431. 10. Leeners B, Damaso F, Ochsenbein-Kölble N, Farquhar C. The effect of pregnancy on endo- metriosis-facts or fiction? Hum Reprod Up- date. 2018;24(3):290-9. doi: 10.1093/humupd/ dmy004. 11. Zermano S, Seminara G, Parisi N, Serantoni V , Arcieri M, Biasioli A, et al. Prenatal Detection and Conservative Management of Uterine Scar Dehiscence in Patient with Previous Uterine Rupture and Multiple Surgeries-A Case Re- port. Healthcare (Basel). 2024;12(10):988. doi: 10.3390/healthcare12100988. 12. Lier MCI, Malik RF, Ket JCF, Lambalk CB, Bro- sens IA, Mijatovic V . Spontaneous hemoperito- neum in pregnancy (SHiP) and endometriosis - A systematic review of the recent literature. Eur J Obstet Gynecol Reprod Biol. 2017;219:57- 65. doi: 10.1016/j.ejogrb.2017.10.012.