{"paper_id":"62a4fd38-c309-4539-b431-51f2b63a3ee9","body_text":"The impact of uterine position on conception modes and perinatal outcomes in nulliparous patients. | 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 The impact of uterine position on conception modes and perinatal outcomes in nulliparous patients. Gal Bachar, Naphtali Justman, Naama Farago, Shira Lieberman, Chen Ben David, and 6 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-4400217/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract Purpose Retroverted uterus affects 15–20% of patients. While typically not a cause for concern, some studies suggest a relationship between a retroverted uterus and subfertility. Study objective was to investigate the association between uterine position and spontaneous conception rates, as well as potential risks for adverse pregnancy outcomes in nulliparous patients. Methods We analyzed data from a retrospective cohort study of 621 nulliparous patients with confirmed pregnancies who received prenatal care at a large medical center between 2006 and 2022. Ultrasound exams documented their uterine position at the beginning of pregnancy. Women were categorized into two groups according to their uterine position. We compared the groups regarding mode of conception (spontaneous/ IVF), pregnancy complications, and vaginal delivery outcomes. Results Compared to patients with anteverted uteri, those with retroverted uteri had a significantly higher rate of conception through IVF (12.3% vs. 6.8%, p = 0.022). IVF indications were similar between groups (p = 0.961). Pregnancy complications, including pre-labor rupture of membranes, miscarriages, and preterm delivery < 37 and < 32 weeks’, were similar. Breech presentation at delivery was comparable between cohorts (~ 6%, p = 0.576). Among patients attempting vaginal delivery (n = 539), cesarean delivery rates were comparable (18.2% anteverted vs. 23.1% retroverted, p = 0.249). No significant differences were observed in other maternal or neonatal outcomes between the groups. Conclusion This study contributes valuable insights into the potential influence of uterine position on pregnancy. While a retroverted uterus does not seem to be a significant risk factor for adverse outcomes, the observed trend regarding its association with IVF pregnancies necessitates further investigation. Retroverted uterus anteverted uterus spontaneous pregnancy trial of labor pregnancy Figures Figure 1 What does this study adds to the clinical wor This study demonstrates a potential association between a retroverted uterus and a higher likelihood of conception through in-vitro fertilization (IVF) in nulliparous patients. However, no significant differences in adverse perinatal outcomes were observed among patients with a retroverted uterus attempting vaginal delivery compared to those with an anteverted uterus. Introduction A retroverted uterus is a common developmental occurrence. Transvaginal ultrasound demonstrates a retroverted uterus in 15–20% of cases, more often in urogynecological patients[ 1 ], [ 2 ]. Acquired uterine retroversion may infrequently coincide with conditions such as endometriosis, pelvic inflammatory disease, or the presence of a displacing pelvic mass[ 3 ], [ 4 ]. Several reports establish a correlation between a retroverted uterus and a higher prevalence of uterine prolapse[ 5 ], bladder dysfunction[ 6 ], unintentional continued pregnancy after failed first-trimester termination[ 7 ], failure of thermal endometrial ablation[ 8 ], and unexplained infertility[ 9 ]. Current infertility assessment focuses mainly on uterine cavity abnormalities and typically does not consider the uterus position per se as a potential infertility factor[ 3 ], [ 10 ], [ 11 ]. During pregnancy, as the uterus enlarges in the early second trimester, the pelvis becomes too small to allow further upward growth of the fundus. The retroverted fundus typically autocorrects itself, rises out of the hollow of the sacrum, and assumes an anterior ventral position[ 12 ], [ 13 ]. Limited literature exists on pregnancy outcomes in patients with retroverted uterus. In 1976, Jordan et al.[ 14 ] compared perinatal complications in 1954 pregnant patients with retroverted uterus to those with anteverted uterus. They reported a significantly higher incidence of first-trimester bleeding and miscarriages but not preterm labor or preeclampsia. However, they did not report other third-trimester perinatal outcomes, and their uterine position diagnosis was clinical, not ultrasound-based. This study investigates the potential association between uterine position (retroverted versus anteverted) and spontaneous conception rates in nulliparous patients. Furthermore, we explore whether a retroverted uterus poses a risk factor for adverse pregnancy outcomes in patients attempting vaginal deliveries. Methods Study procedures This is a retrospective single-center cohort study of patients at a tertiary referral center between January 2006 and January 2022. The hospital's Institutional Review Board approved the study (IRB-0129-22-RMB) and waived informed consent. Patient data, including demographics, general medical history, and gynecologic-obstetric characteristics, were retrieved from the hospital's electronic medical record system. Study protocol All patients of reproductive age (15–49 years) with a confirmed pregnancy who presented to our obstetrics and gynecology triage or ultrasound unit up to 13 weeks and 6 days gestation (the upper limit for nuchal translucency aneuploidy screening) with transvaginal ultrasound documentation of their uterus position were initially considered for eligibility. The initial cohort for analysis comprised nulliparous patients with singleton pregnancies who received prenatal care and delivered at our institution during the study period. Patients were categorized into two groups according to their uterine position: anteverted or retroverted. The primary outcome of the study was the mode of conception. Among the secondary outcomes were perinatal characteristics such as maternal comorbidities (gestational diabetes and preeclampsia), rates of pre-labor rupture of membranes (PROM), miscarriage < 24 weeks, preterm deliveries < 37 and 32 weeks of gestation, and breech presentation at term. In a subsequent sub-analysis, we intentionally excluded scheduled cesarean deliveries and examined whether anteverted or retroverted uterine positions influenced perinatal outcomes, with a specific focus on patients attempting vaginal deliveries. Outcome measures included mode of delivery, rates of postpartum hemorrhage, retained products of conception, Apgar score < 7 at 5 minutes, and admission to the neonatal intensive care unit (NICU). Statistical analysis We conducted a comparative analysis of baseline patient characteristics and pregnancy outcomes among nulliparous patients with anteverted and retroverted uteri. Categorical variables were expressed as numbers with corresponding percentages and assessed using the chi-square test. Continuous variables were presented as means and standard deviations and subjected to analysis using either the Student's t-test for normally distributed samples or the Mann-Whitney test for non-normally distributed samples. Statistical significance was set at p < 0.05. Data management and statistical analyses were performed using SPSS for Windows (version 28) by SPSS Inc., based in Chicago, IL. Results Figure 1 depicts the inclusion-exclusion flow chart of the study. Initially, transvaginal ultrasound documented the uterine position for 2306 patients; after exclusions, the final primary analysis comprised 621 nulliparous patients. Among them, 409 (65.86%) had an anteverted uterus, while 212 (34.14%) had a retroverted uterus. In the subsequent analysis, 539 nulliparous patients underwent a trial of vaginal delivery, with 362 (67.16%) having an anteverted uterus and 177 (32.84%) having a retroverted uterus. Table 1 summarizes the demographic and pregnancy characteristics of nulliparous patients with known uterine positions based on ultrasound. There were no statistically significant differences between the groups in maternal age, body mass index, or history of miscarriage. Patients with a retroverted uterus exhibited significantly higher rates of conception through IVF compared to those with an anteverted uterus (12.3% vs. 6.8%, p=0.022). The indications for IVF were similar between groups, including unexplained infertility, male factor, endometriosis, and polycystic ovary syndrome (p=0.961). Other pregnancy complications, including PROM, miscarriage before 24 weeks, and preterm delivery before both 37 and 32 weeks of gestation, were similar between the groups. Breech presentation at delivery was also comparable between the anteverted and retroverted groups (5.9% vs. 6.6%, p=0.576). Table 2 presents perinatal outcomes for nulliparous patients with known uterine positions who attempted vaginal delivery. Cesarean delivery rates were comparable between the anteverted and retroverted groups (18.2% vs. 23.1%, respectively, p=0.249). Rates of postpartum hemorrhage (4.1% vs. 6.2%, p=0.292), retained products of conception (9.9% vs. 12.4%, p=0.379), small for gestational age < 2,500g (9.1% vs. 9.6%, p=0.875) and admission to NICU (4.4% vs. 6.8%, p=0.302) were all also comparable between the anteverted and retroverted groups. Discussion While nearly 1 in 5 patients have a retroverted uterus, this aspect has garnered limited attention in perinatal research to date[ 1 ], [ 2 ]. In the present study, we found that nulliparous patients with a retroverted uterus have decreased rates of spontaneous pregnancies, thereby requiring IVF treatment in comparison to their counterparts with an anteverted uterus. Our finding stands a two-fold elevation from the globally reported rates of 1–5% for all pregnancies[ 10 ], [ 15 ], [ 16 ]. Nevertheless, in nulliparous patients attempting vaginal deliveries, our analysis showed no differences in adverse perinatal outcomes between the groups. The literature regarding pre-gestational uterine position and spontaneous pregnancy is scarce. While the exact reasons remain unclear, some studies[ 10 ], [ 15 ], [ 16 ], [ 17 ] propose that a retroverted uterus might alter sperm transport or embryo implantation efficiency. On the other hand, the clinical pregnancy rate was found to be comparable when using IVF among patients with anteverted and retroverted uterus[ 18 ]. Our initial theory appears to be supported based on the above notions and current study findings of a possible association between a retroverted uterus and a lower likelihood of natural conception. Initially, it is suggested that a retroverted uterus with a pronounced posterior flexion might impede the natural postcoital sperm transport toward the fallopian tubes, potentially compromising the probability of natural conception. Secondly, during IVF, the fertilized ovum is transferred directly into the uterine cavity under ultrasound guidance. This process bypasses any obstacles related to uterine angulation or the presence of uterine anomalies. Consequently, it ensures a successful IVF implantation irrespective of uterine position. Evidence supporting the association between the retroverted uterus and the heightened need for IVF could be further extrapolated from a sub-analysis of the causes of IVF. Unexplained infertility, accounting for over 60% of cases, prevailed as the primary indication for IVF in both retroverted and anteverted groups. This finding underscores the possibility of other underlying factors contributing to the need for IVF within this subset of unexplained infertility patients, of which retroverted uterus could be a contributing factor. Contrary to our initial hypothesis, the study findings did not indicate a higher incidence of adverse pregnancy outcomes, particularly of intrapartum cesarean deliveries, among nulliparous patients attempting vaginal deliveries in the retroverted group compared to the anteverted group. A plausible explanation might be the \"autocorrection\" phenomenon[ 3 ], [ 19 ], [ 20 ], [ 21 ], [ 22 ], [ 23 ]. During pregnancy, particularly in the early second trimester beyond 14 weeks of gestation, any retroverted uterus typically autocorrects itself, rises out of the hollow of the sacrum, and assumes an anterior ventral position[ 3 ]. If this physiological autocorrection adaptation fails, the axis of the retroverted uterus is altered, and the cervix is anteriorly placed in the vagina close to the bladder, leading to reported cases of incarceration[ 11 ], [ 12 ]. Our study possesses robust strengths. It is the first to explore the association between uterine position and the necessity for IVF. Additionally, we ensured reliability through formal documentation of uterine position via transvaginal ultrasound in all cases. Furthermore, our homogeneous study population and utilization of a real-time electronic database minimize the possibility of bias. Several limitations warrant acknowledgment. Firstly, our reliance on data from a single tertiary center may limit the generalizability of findings. Secondly, our sample size remained relatively small despite an extended study period due to historical documentation practices, excluding potential participants. Lastly, the retrospective nature of our study introduces constraints associated with incomplete database capture. In conclusion, our findings suggest an association between a retroverted uterus and a higher likelihood of conceiving after IVF treatment. They also underscore the importance of thorough fertility evaluation for patients with a retroverted uterus, mainly when infertility causes are not readily apparent. Importantly, our findings provide reassurance by suggesting that a retroverted uterus does not correlate with adverse pregnancy outcomes during attempted vaginal delivery. Prospective studies are warranted to ascertain our findings. Declarations Funding: The authors declare that no funds, grants, or other support were received during the preparation of this manuscript. Competing Interests: The authors have no relevant financial or non-financial interests to disclose. Acknowledgments : None. Author contribution : G Bachar Protocol/project development and Manuscript writing/editing N Justman Data analysis N Farago Data collection S Lieberman Data management C Ben-David Protocol/project development O Fainaru Manuscript writing/editing N Khatib Manuscript writing/editing R Beloosesky Manuscript writing/editing D Vitner Manuscript writing/editing Z Weiner Manuscript writing/editing Y Zipori Protocol/project development and Manuscript writing/editing Ethics approval: This study was performed in line with the principles of the Declaration of Helsinki. Approval was granted by the Ethics Committee of Rambem medical health campus IRB-0129-22-RMB. Consent to participate : since it was a retrospective study, the hospital's Institutional Review Board waived informed consent. Declaration of generative AI in scientific writing: None. References Freimanis MG, Jones AF (1992) Transvaginal ultrasonography. Radiol Clin North Am 30:5 Haylen BT, Mcnally G, Ramsay P, Birrell W, Logan V (2007) A standardised ultrasonic diagnosis and an accurate prevalence for the retroverted uterus in general gynaecology patients. Aust N Z J Obstet Gynaecol 47(4). 10.1111/j.1479-828X.2007.00745.x Seracchioli R et al (2019) Transvaginal and transperineal ultrasound follow-up after laparoscopic correction of uterine retrodisplacement in women with posterior deep infiltrating endometriosis. Aust N Z J Obstet Gynaecol 59(2). 10.1111/ajo.12882 Alam A (2006) Fundamentals of Obstetrics and Gynaecology, 8th edition, The Obstetrician & Gynaecologist , vol. 8, no. 1, 10.1576/toag.8.1.061.27212 Haylen BT (2006) The retroverted uterus: Ignored to date but core to prolapse. Int Urogynecol J 17(6). 10.1007/s00192-005-0051-0 Weinberger MW, Julian TM (1995) Voiding dysfunction and incontinence caused by uterine retroversion: A case report. J Reproductive Med Obstetrician Gynecologist, 40, 5 Fielding WL, Lee SY, Friedman EA (1978) Continued pregnancy after failed first trimester abortion. Obstet Gynecol, 52, 1 Amso NN et al (2003) Uterine endometrial thermal balloon therapy for the treatment of menorrhagia: Long-term multicentre follow-up study. Hum Reprod 18(5). 10.1093/humrep/deg206 PEPPERELL RJ, McBAIN JC (1985) Unexplained infertility: a review. BJOG 92(6). 10.1111/j.1471-0528.1985.tb01394.x Romualdi D et al (2023) Evidence-based guideline: unexplained infertility. Hum Reprod 38(10). 10.1093/humrep/dead150 BOOK REVIEWS, (1982) BJOG 89(5). 10.1111/j.1471-0528.1982.tb05088.x Smalbraak I, Bleker OP, Schutte MF, Treffers PE (1991) Incarceration of the retroverted gravid uterus: a report of four cases. Eur J Obstet Gynecol Reproductive Biology 39(2). 10.1016/0028-2243(91)90080-5 Jacobsson B, Wide-Swensson D (1999) Incarceration of the retroverted gravid uterus ‐‐ a review. Acta Obstet Gynecol Scand 78(8). 10.1034/j.1600-0412.1999.780801.x Jordan EC, Murray SM, Brown VA (1976) The retroverted gravid uterus and its effect on the outcome of pregnancy. Br Med J 1(6010). 10.1136/bmj.1.6010.622 De Geyter C et al (2018) ART in Europe, 2014: Results generated from European registries by ESHRE. Hum Reprod. 10.1093/humrep/dey242 Dupree JM et al (2019) Provision of insurance coverage for IVF by a large employer and changes in IVF rates among health plan enrollees. JAMA - J Am Med Association 322:19. 10.1001/jama.2019.16055 Sunderam S et al (2018) Assisted Reproductive Technology Surveillance — United States, MMWR Surveillance Summaries , vol. 71, no. 4, 2022, 10.15585/MMWR.SS7104A1 Agarwal SK, Coe S, Buyalos RP (1994) The influence of uterine position on pregnancy rates with in vitro fertilization-embryo transfer. J Assist Reprod Genet 11(6). 10.1007/BF02215722 Tissot M, Lecointre L, Faller E, Afors K, Akladios C, Audebert A (2017) Clinical presentation of endometriosis identified at interval laparoscopic tubal sterilization: Prospective series of 465 cases. J Gynecol Obstet Hum Reprod 46(8). 10.1016/j.jogoh.2017.05.003 Moen MH, Muus KM (1991) Endometriosis in pregnant and non-pregnant women at tubal sterilization. Hum Reprod 6(5). 10.1093/oxfordjournals.humrep.a137411 Lalani S et al (2018) Endometriosis and adverse maternal, fetal and neonatal outcomes, a systematic review and meta-analysis. Hum Reprod 33(10). 10.1093/humrep/dey269 Farland LV et al (2022) Pregnancy outcomes among women with endometriosis and fibroids: registry linkage study in Massachusetts. Am J Obstet Gynecol 226(6). 10.1016/j.ajog.2021.12.268 Glavind K, Bjørk J (2003) Incidence and treatment of urinary retention postpartum. Int Urogynecol J. 10.1007/s00192-002-1014-3 Tables Table 1. Demographic and pregnancy characteristics of nulliparous patients with anteverted vs. retroverted uteri. Anteverted uterus n=409 Retroverted uterus n= 212 P-Value Maternal age, years, mean + SD 27.46 + 4.77 28.19 + 5.68 0.360 Body Mass Index, kg/m 2 , mean + SD 29.26 + 4.66 29.30 + 5.42 0.872 Hx of miscarriage, n (%) 97 (23.7) 48 (22.6) 0.842 In vitro fertilization, n (%) 28 (6.8) 26 (12.3) 0.022 IVF indication, n (%) Unexplained Male factor Endometriosis Polycystic ovary syndrome 17 (60.7) 6 (21.4) 3 (10.7) 2 (7.1) 16 (61.5) 6 (23.1) 3 (11.5) 1 (3.8) 0.961 Pre-labor rupture of membranes, n (%) 71 (17.4) 37 (17.5) 1.000 Gestational diabetes mellitus, n (%) 33 (8.1) 14 (6.6) 0.51 Preeclampsia, n (%) 27 (6.6) 20 (9.4) 0.21 Miscarriage < 24 weeks, n (%) 4 (1) 3 (1.4) 0.62 Preterm delivery < 37 weeks, n (%) Preterm delivery < 32 weeks, n (%) 50 (12.2) 15 (3.7) 35 (16.5) 9 (4.2) 0.142 0.827 Breech presentation, n (%) 24 (5.9) 14 (6.6) 0.576 SD, standard deviation; n, number. P < 0.05 was considered significant. Table 2. Comparative maternal and neonatal outcomes in patients with anteverted vs. retroverted uteri attempting vaginal delivery. Anteverted uterus n=362 Retroverted uterus n= 177 P-Value Gestational age at delivery, weeks, mean +/- S.D. 39 + 2.5 38.9 + 2.9 0.903 Mode of delivery, n (%) Spontaneous vaginal delivery Operative vaginal delivery Cesarean delivery 242 (66.9) 54 (14.9) 66 (18.2) 112 (63.3) 24 (13.6) 41 (23.1) 0.249 Delivery gestational age, weeks, mean + SD 39 + 2.5 38.9 + 2.9 0.903 Postpartum hemorrhage, n (%) 15 (4.1) 11 (6.2) 0.292 Retained products of conception, n (%) 36 (9.9) 22 (12.4) 0.379 Birthweight at delivery, grams, mean + SD 3128.2 + 547 3083.3 + 643 0.578 Birthweight at delivery < 2,500 g, n (%) 33 (9.1) 17 (9.6) 0.875 Apgar score at 5 min < 7, n (%) 8 (2.2) 3 (1.7) 1.00 Admission to NICU, n (%) 16 (4.4) 12 (6.8) 0.302 n, number; NICU, neonatal intensive care unit. P < 0.05 was considered significant. 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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-4400217\",\"acceptedTermsAndConditions\":true,\"allowDirectSubmit\":true,\"archivedVersions\":[],\"articleType\":\"Research Article\",\"associatedPublications\":[],\"authors\":[{\"id\":311223230,\"identity\":\"dae3a278-470a-47d4-b48e-3b0d7696a4c5\",\"order_by\":0,\"name\":\"Gal Bachar\",\"email\":\"\",\"orcid\":\"https://orcid.org/0000-0002-6290-2945\",\"institution\":\"Rambam Medical Center: Rambam Health Care 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19:54:44\",\"extension\":\"pdf\",\"order_by\":0,\"title\":\"\",\"display\":\"\",\"copyAsset\":false,\"role\":\"manuscript-pdf\",\"size\":1152350,\"visible\":true,\"origin\":\"\",\"legend\":\"\",\"description\":\"\",\"filename\":\"manuscript.pdf\",\"url\":\"https://assets-eu.researchsquare.com/files/rs-4400217/v1/87c57c6b-430f-4a3f-9fe1-78f1040151e4.pdf\"}],\"financialInterests\":\"\",\"formattedTitle\":\"The impact of uterine position on conception modes and perinatal outcomes in nulliparous patients.\",\"fulltext\":[{\"header\":\"What does this study adds to the clinical wor\",\"content\":\"\\u003cp\\u003eThis study demonstrates a potential association between a retroverted uterus and a higher likelihood of conception through in-vitro fertilization (IVF) in nulliparous patients. However, no significant differences in adverse perinatal outcomes were observed among patients with a retroverted uterus attempting vaginal delivery compared to those with an anteverted uterus.\\u003c/p\\u003e\"},{\"header\":\"Introduction\",\"content\":\"\\u003cp\\u003eA retroverted uterus is a common developmental occurrence. Transvaginal ultrasound demonstrates a retroverted uterus in 15\\u0026ndash;20% of cases, more often in urogynecological patients[\\u003cspan citationid=\\\"CR1\\\" class=\\\"CitationRef\\\"\\u003e1\\u003c/span\\u003e], [\\u003cspan citationid=\\\"CR2\\\" class=\\\"CitationRef\\\"\\u003e2\\u003c/span\\u003e]. Acquired uterine retroversion may infrequently coincide with conditions such as endometriosis, pelvic inflammatory disease, or the presence of a displacing pelvic mass[\\u003cspan citationid=\\\"CR3\\\" class=\\\"CitationRef\\\"\\u003e3\\u003c/span\\u003e], [\\u003cspan citationid=\\\"CR4\\\" class=\\\"CitationRef\\\"\\u003e4\\u003c/span\\u003e].\\u003c/p\\u003e \\u003cp\\u003eSeveral reports establish a correlation between a retroverted uterus and a higher prevalence of uterine prolapse[\\u003cspan citationid=\\\"CR5\\\" class=\\\"CitationRef\\\"\\u003e5\\u003c/span\\u003e], bladder dysfunction[\\u003cspan citationid=\\\"CR6\\\" class=\\\"CitationRef\\\"\\u003e6\\u003c/span\\u003e], unintentional continued pregnancy after failed first-trimester termination[\\u003cspan citationid=\\\"CR7\\\" class=\\\"CitationRef\\\"\\u003e7\\u003c/span\\u003e], failure of thermal endometrial ablation[\\u003cspan citationid=\\\"CR8\\\" class=\\\"CitationRef\\\"\\u003e8\\u003c/span\\u003e], and unexplained infertility[\\u003cspan citationid=\\\"CR9\\\" class=\\\"CitationRef\\\"\\u003e9\\u003c/span\\u003e]. Current infertility assessment focuses mainly on uterine cavity abnormalities and typically does not consider the uterus position per se as a potential infertility factor[\\u003cspan citationid=\\\"CR3\\\" class=\\\"CitationRef\\\"\\u003e3\\u003c/span\\u003e], [\\u003cspan citationid=\\\"CR10\\\" class=\\\"CitationRef\\\"\\u003e10\\u003c/span\\u003e], [\\u003cspan citationid=\\\"CR11\\\" class=\\\"CitationRef\\\"\\u003e11\\u003c/span\\u003e].\\u003c/p\\u003e \\u003cp\\u003eDuring pregnancy, as the uterus enlarges in the early second trimester, the pelvis becomes too small to allow further upward growth of the fundus. The retroverted fundus typically autocorrects itself, rises out of the hollow of the sacrum, and assumes an anterior ventral position[\\u003cspan citationid=\\\"CR12\\\" class=\\\"CitationRef\\\"\\u003e12\\u003c/span\\u003e], [\\u003cspan citationid=\\\"CR13\\\" class=\\\"CitationRef\\\"\\u003e13\\u003c/span\\u003e]. Limited literature exists on pregnancy outcomes in patients with retroverted uterus. In 1976, Jordan et al.[\\u003cspan citationid=\\\"CR14\\\" class=\\\"CitationRef\\\"\\u003e14\\u003c/span\\u003e] compared perinatal complications in 1954 pregnant patients with retroverted uterus to those with anteverted uterus. They reported a significantly higher incidence of first-trimester bleeding and miscarriages but not preterm labor or preeclampsia. However, they did not report other third-trimester perinatal outcomes, and their uterine position diagnosis was clinical, not ultrasound-based.\\u003c/p\\u003e \\u003cp\\u003eThis study investigates the potential association between uterine position (retroverted versus anteverted) and spontaneous conception rates in nulliparous patients. Furthermore, we explore whether a retroverted uterus poses a risk factor for adverse pregnancy outcomes in patients attempting vaginal deliveries.\\u003c/p\\u003e\"},{\"header\":\"Methods\",\"content\":\"\\u003cdiv id=\\\"Sec3\\\" class=\\\"Section2\\\"\\u003e \\u003ch2\\u003eStudy procedures\\u003c/h2\\u003e \\u003cp\\u003eThis is a retrospective single-center cohort study of patients at a tertiary referral center between January 2006 and January 2022. The hospital's Institutional Review Board approved the study (IRB-0129-22-RMB) and waived informed consent. Patient data, including demographics, general medical history, and gynecologic-obstetric characteristics, were retrieved from the hospital's electronic medical record system.\\u003c/p\\u003e \\u003c/div\\u003e \\u003cdiv id=\\\"Sec4\\\" class=\\\"Section2\\\"\\u003e \\u003ch2\\u003eStudy protocol\\u003c/h2\\u003e \\u003cp\\u003eAll patients of reproductive age (15\\u0026ndash;49 years) with a confirmed pregnancy who presented to our obstetrics and gynecology triage or ultrasound unit up to 13 weeks and 6 days gestation (the upper limit for nuchal translucency aneuploidy screening) with transvaginal ultrasound documentation of their uterus position were initially considered for eligibility.\\u003c/p\\u003e \\u003cp\\u003eThe initial cohort for analysis comprised nulliparous patients with singleton pregnancies who received prenatal care and delivered at our institution during the study period. Patients were categorized into two groups according to their uterine position: anteverted or retroverted. The primary outcome of the study was the mode of conception. Among the secondary outcomes were perinatal characteristics such as maternal comorbidities (gestational diabetes and preeclampsia), rates of pre-labor rupture of membranes (PROM), miscarriage\\u0026thinsp;\\u0026lt;\\u0026thinsp;24 weeks, preterm deliveries\\u0026thinsp;\\u0026lt;\\u0026thinsp;37 and 32 weeks of gestation, and breech presentation at term.\\u003c/p\\u003e \\u003cp\\u003eIn a subsequent sub-analysis, we intentionally excluded scheduled cesarean deliveries and examined whether anteverted or retroverted uterine positions influenced perinatal outcomes, with a specific focus on patients attempting vaginal deliveries. Outcome measures included mode of delivery, rates of postpartum hemorrhage, retained products of conception, Apgar score\\u0026thinsp;\\u0026lt;\\u0026thinsp;7 at 5 minutes, and admission to the neonatal intensive care unit (NICU).\\u003c/p\\u003e \\u003c/div\\u003e \\u003cdiv id=\\\"Sec5\\\" class=\\\"Section2\\\"\\u003e \\u003ch2\\u003eStatistical analysis\\u003c/h2\\u003e \\u003cp\\u003eWe conducted a comparative analysis of baseline patient characteristics and pregnancy outcomes among nulliparous patients with anteverted and retroverted uteri. Categorical variables were expressed as numbers with corresponding percentages and assessed using the chi-square test. Continuous variables were presented as means and standard deviations and subjected to analysis using either the Student's t-test for normally distributed samples or the Mann-Whitney test for non-normally distributed samples. Statistical significance was set at p\\u0026thinsp;\\u0026lt;\\u0026thinsp;0.05. Data management and statistical analyses were performed using SPSS for Windows (version 28) by SPSS Inc., based in Chicago, IL.\\u003c/p\\u003e \\u003c/div\\u003e\"},{\"header\":\"Results\",\"content\":\"\\u003cp\\u003eFigure 1 depicts the inclusion-exclusion flow chart of the study. Initially, transvaginal ultrasound documented the uterine position for 2306 patients; after exclusions, the final primary analysis comprised 621 nulliparous patients. Among them, 409 (65.86%) had an anteverted uterus, while 212 (34.14%) had a retroverted uterus. In the subsequent analysis, 539 nulliparous patients underwent a trial of vaginal delivery, with 362 (67.16%) having an anteverted uterus and 177 (32.84%) having a retroverted uterus.\\u003c/p\\u003e\\n\\u003cp\\u003eTable 1 summarizes the demographic and pregnancy characteristics of nulliparous patients with known uterine positions based on ultrasound.\\u0026nbsp;There were no statistically significant differences between the groups in maternal age, body mass index, or history of miscarriage. Patients with a retroverted uterus exhibited significantly higher rates of conception through IVF compared to those with an anteverted uterus (12.3% vs. 6.8%, p=0.022). The indications for IVF \\u0026nbsp;were similar between groups, including unexplained infertility, male factor, endometriosis, and polycystic ovary syndrome (p=0.961). Other pregnancy complications, including PROM, miscarriage before 24 weeks, and preterm delivery before both 37 and 32 weeks of gestation, were similar between the groups.\\u0026nbsp;Breech presentation at delivery was also comparable between the anteverted and retroverted groups (5.9% vs. 6.6%, p=0.576).\\u003c/p\\u003e\\n\\u003cp\\u003eTable 2 presents perinatal outcomes for nulliparous patients with known uterine positions who attempted vaginal delivery. Cesarean delivery rates were comparable between the anteverted and retroverted groups (18.2% vs. 23.1%, respectively, p=0.249). Rates of postpartum hemorrhage (4.1% vs. 6.2%, p=0.292), retained products of conception (9.9% vs. 12.4%, p=0.379), small for gestational age \\u0026lt; 2,500g (9.1% vs. 9.6%, p=0.875) and admission to NICU (4.4% vs. 6.8%, p=0.302) were all also comparable between the anteverted and retroverted groups.\\u003c/p\\u003e\"},{\"header\":\"Discussion\",\"content\":\"\\u003cp\\u003eWhile nearly 1 in 5 patients have a retroverted uterus, this aspect has garnered limited attention in perinatal research to date[\\u003cspan citationid=\\\"CR1\\\" class=\\\"CitationRef\\\"\\u003e1\\u003c/span\\u003e], [\\u003cspan citationid=\\\"CR2\\\" class=\\\"CitationRef\\\"\\u003e2\\u003c/span\\u003e]. In the present study, we found that nulliparous patients with a retroverted uterus have decreased rates of spontaneous pregnancies, thereby requiring IVF treatment in comparison to their counterparts with an anteverted uterus. Our finding stands a two-fold elevation from the globally reported rates of 1\\u0026ndash;5% for all pregnancies[\\u003cspan citationid=\\\"CR10\\\" class=\\\"CitationRef\\\"\\u003e10\\u003c/span\\u003e], [\\u003cspan citationid=\\\"CR15\\\" class=\\\"CitationRef\\\"\\u003e15\\u003c/span\\u003e], [\\u003cspan citationid=\\\"CR16\\\" class=\\\"CitationRef\\\"\\u003e16\\u003c/span\\u003e]. Nevertheless, in nulliparous patients attempting vaginal deliveries, our analysis showed no differences in adverse perinatal outcomes between the groups.\\u003c/p\\u003e \\u003cp\\u003eThe literature regarding pre-gestational uterine position and spontaneous pregnancy is scarce. While the exact reasons remain unclear, some studies[\\u003cspan citationid=\\\"CR10\\\" class=\\\"CitationRef\\\"\\u003e10\\u003c/span\\u003e], [\\u003cspan citationid=\\\"CR15\\\" class=\\\"CitationRef\\\"\\u003e15\\u003c/span\\u003e], [\\u003cspan citationid=\\\"CR16\\\" class=\\\"CitationRef\\\"\\u003e16\\u003c/span\\u003e], [\\u003cspan citationid=\\\"CR17\\\" class=\\\"CitationRef\\\"\\u003e17\\u003c/span\\u003e] propose that a retroverted uterus might alter sperm transport or embryo implantation efficiency. On the other hand, the clinical pregnancy rate was found to be comparable when using IVF among patients with anteverted and retroverted uterus[\\u003cspan citationid=\\\"CR18\\\" class=\\\"CitationRef\\\"\\u003e18\\u003c/span\\u003e]. Our initial theory appears to be supported based on the above notions and current study findings of a possible association between a retroverted uterus and a lower likelihood of natural conception. Initially, it is suggested that a retroverted uterus with a pronounced posterior flexion might impede the natural postcoital sperm transport toward the fallopian tubes, potentially compromising the probability of natural conception. Secondly, during IVF, the fertilized ovum is transferred directly into the uterine cavity under ultrasound guidance. This process bypasses any obstacles related to uterine angulation or the presence of uterine anomalies. Consequently, it ensures a successful IVF implantation irrespective of uterine position.\\u003c/p\\u003e \\u003cp\\u003eEvidence supporting the association between the retroverted uterus and the heightened need for IVF could be further extrapolated from a sub-analysis of the causes of IVF. Unexplained infertility, accounting for over 60% of cases, prevailed as the primary indication for IVF in both retroverted and anteverted groups. This finding underscores the possibility of other underlying factors contributing to the need for IVF within this subset of unexplained infertility patients, of which retroverted uterus could be a contributing factor.\\u003c/p\\u003e \\u003cp\\u003eContrary to our initial hypothesis, the study findings did not indicate a higher incidence of adverse pregnancy outcomes, particularly of intrapartum cesarean deliveries, among nulliparous patients attempting vaginal deliveries in the retroverted group compared to the anteverted group. A plausible explanation might be the \\\"autocorrection\\\" phenomenon[\\u003cspan citationid=\\\"CR3\\\" class=\\\"CitationRef\\\"\\u003e3\\u003c/span\\u003e], [\\u003cspan citationid=\\\"CR19\\\" class=\\\"CitationRef\\\"\\u003e19\\u003c/span\\u003e], [\\u003cspan citationid=\\\"CR20\\\" class=\\\"CitationRef\\\"\\u003e20\\u003c/span\\u003e], [\\u003cspan citationid=\\\"CR21\\\" class=\\\"CitationRef\\\"\\u003e21\\u003c/span\\u003e], [\\u003cspan citationid=\\\"CR22\\\" class=\\\"CitationRef\\\"\\u003e22\\u003c/span\\u003e], [\\u003cspan citationid=\\\"CR23\\\" class=\\\"CitationRef\\\"\\u003e23\\u003c/span\\u003e]. During pregnancy, particularly in the early second trimester beyond 14 weeks of gestation, any retroverted uterus typically autocorrects itself, rises out of the hollow of the sacrum, and assumes an anterior ventral position[\\u003cspan citationid=\\\"CR3\\\" class=\\\"CitationRef\\\"\\u003e3\\u003c/span\\u003e]. If this physiological autocorrection adaptation fails, the axis of the retroverted uterus is altered, and the cervix is anteriorly placed in the vagina close to the bladder, leading to reported cases of incarceration[\\u003cspan citationid=\\\"CR11\\\" class=\\\"CitationRef\\\"\\u003e11\\u003c/span\\u003e], [\\u003cspan citationid=\\\"CR12\\\" class=\\\"CitationRef\\\"\\u003e12\\u003c/span\\u003e].\\u003c/p\\u003e \\u003cp\\u003eOur study possesses robust strengths. It is the first to explore the association between uterine position and the necessity for IVF. Additionally, we ensured reliability through formal documentation of uterine position via transvaginal ultrasound in all cases. Furthermore, our homogeneous study population and utilization of a real-time electronic database minimize the possibility of bias. Several limitations warrant acknowledgment. Firstly, our reliance on data from a single tertiary center may limit the generalizability of findings. Secondly, our sample size remained relatively small despite an extended study period due to historical documentation practices, excluding potential participants. Lastly, the retrospective nature of our study introduces constraints associated with incomplete database capture.\\u003c/p\\u003e \\u003cp\\u003eIn conclusion, our findings suggest an association between a retroverted uterus and a higher likelihood of conceiving after IVF treatment. They also underscore the importance of thorough fertility evaluation for patients with a retroverted uterus, mainly when infertility causes are not readily apparent. Importantly, our findings provide reassurance by suggesting that a retroverted uterus does not correlate with adverse pregnancy outcomes during attempted vaginal delivery. Prospective studies are warranted to ascertain our findings.\\u003c/p\\u003e\"},{\"header\":\"Declarations\",\"content\":\"\\u003cp\\u003e\\u003cstrong\\u003eFunding:\\u0026nbsp;\\u003c/strong\\u003eThe authors declare that no funds, grants, or other support were received during the preparation of this manuscript.\\u003c/p\\u003e\\n\\u003cp\\u003e\\u003cstrong\\u003eCompeting Interests:\\u0026nbsp;\\u003c/strong\\u003eThe authors have no relevant financial or non-financial interests to disclose.\\u003c/p\\u003e\\n\\u003cp\\u003e\\u003cstrong\\u003eAcknowledgments\\u003c/strong\\u003e: None.\\u003c/p\\u003e\\n\\u003cp\\u003e\\u003cstrong\\u003eAuthor contribution\\u003c/strong\\u003e:\\u003c/p\\u003e\\n\\u003cp\\u003eG Bachar Protocol/project development and Manuscript writing/editing\\u003c/p\\u003e\\n\\u003cp\\u003eN\\u0026nbsp;Justman Data analysis\\u003c/p\\u003e\\n\\u003cp\\u003eN Farago Data collection\\u0026nbsp;\\u003c/p\\u003e\\n\\u003cp\\u003eS Lieberman Data management\\u003c/p\\u003e\\n\\u003cp\\u003eC Ben-David Protocol/project development\\u003c/p\\u003e\\n\\u003cp\\u003eO Fainaru Manuscript writing/editing\\u003c/p\\u003e\\n\\u003cp\\u003eN Khatib Manuscript writing/editing\\u003c/p\\u003e\\n\\u003cp\\u003eR Beloosesky Manuscript writing/editing\\u003c/p\\u003e\\n\\u003cp\\u003eD Vitner Manuscript writing/editing\\u003c/p\\u003e\\n\\u003cp\\u003eZ Weiner\\u0026nbsp;Manuscript writing/editing\\u003c/p\\u003e\\n\\u003cp\\u003eY Zipori\\u0026nbsp;Protocol/project development and Manuscript writing/editing\\u003c/p\\u003e\\n\\u003cp\\u003e\\u003cstrong\\u003eEthics approval:\\u0026nbsp;\\u003c/strong\\u003eThis study was performed in line with the principles of the Declaration of Helsinki. Approval was granted by the Ethics Committee of\\u003cstrong\\u003e\\u0026nbsp;\\u003c/strong\\u003eRambem medical health campus\\u0026nbsp;IRB-0129-22-RMB.\\u003c/p\\u003e\\n\\u003cp\\u003e\\u003cstrong\\u003eConsent to participate\\u003c/strong\\u003e: since it was a retrospective study, the hospital\\u0026apos;s Institutional Review Board waived informed consent.\\u003c/p\\u003e\\n\\u003cp\\u003e\\u003cstrong\\u003eDeclaration of generative AI in scientific writing:\\u0026nbsp;\\u003c/strong\\u003eNone.\\u0026nbsp;\\u003c/p\\u003e\"},{\"header\":\"References\",\"content\":\"\\u003col\\u003e\\u003cli\\u003e\\u003cspan\\u003eFreimanis MG, Jones AF (1992) Transvaginal ultrasonography. Radiol Clin North Am 30:5\\u003c/span\\u003e\\u003c/li\\u003e \\u003cli\\u003e\\u003cspan\\u003eHaylen BT, Mcnally G, Ramsay P, Birrell W, Logan V (2007) A standardised ultrasonic diagnosis and an accurate prevalence for the retroverted uterus in general gynaecology patients. Aust N Z J Obstet Gynaecol 47(4). \\u003cspan class=\\\"ExternalRef\\\"\\u003e\\u003cspan class=\\\"RefSource\\\"\\u003e10.1111/j.1479-828X.2007.00745.x\\u003c/span\\u003e\\u003cspan address=\\\"10.1111/j.1479-828X.2007.00745.x\\\" targettype=\\\"DOI\\\" class=\\\"RefTarget\\\"\\u003e\\u003c/span\\u003e\\u003c/span\\u003e\\u003c/span\\u003e\\u003c/li\\u003e \\u003cli\\u003e\\u003cspan\\u003eSeracchioli R et al (2019) Transvaginal and transperineal ultrasound follow-up after laparoscopic correction of uterine retrodisplacement in women with posterior deep infiltrating endometriosis. Aust N Z J Obstet Gynaecol 59(2). \\u003cspan class=\\\"ExternalRef\\\"\\u003e\\u003cspan class=\\\"RefSource\\\"\\u003e10.1111/ajo.12882\\u003c/span\\u003e\\u003cspan address=\\\"10.1111/ajo.12882\\\" targettype=\\\"DOI\\\" class=\\\"RefTarget\\\"\\u003e\\u003c/span\\u003e\\u003c/span\\u003e\\u003c/span\\u003e\\u003c/li\\u003e \\u003cli\\u003e\\u003cspan\\u003eAlam A (2006) Fundamentals of Obstetrics and Gynaecology, 8th edition, \\u003cem\\u003eThe Obstetrician \\u0026amp; Gynaecologist\\u003c/em\\u003e, vol. 8, no. 1, \\u003cspan class=\\\"ExternalRef\\\"\\u003e\\u003cspan class=\\\"RefSource\\\"\\u003e10.1576/toag.8.1.061.27212\\u003c/span\\u003e\\u003cspan address=\\\"10.1576/toag.8.1.061.27212\\\" targettype=\\\"DOI\\\" class=\\\"RefTarget\\\"\\u003e\\u003c/span\\u003e\\u003c/span\\u003e\\u003c/span\\u003e\\u003c/li\\u003e \\u003cli\\u003e\\u003cspan\\u003eHaylen BT (2006) The retroverted uterus: Ignored to date but core to prolapse. Int Urogynecol J 17(6). \\u003cspan class=\\\"ExternalRef\\\"\\u003e\\u003cspan class=\\\"RefSource\\\"\\u003e10.1007/s00192-005-0051-0\\u003c/span\\u003e\\u003cspan address=\\\"10.1007/s00192-005-0051-0\\\" targettype=\\\"DOI\\\" class=\\\"RefTarget\\\"\\u003e\\u003c/span\\u003e\\u003c/span\\u003e\\u003c/span\\u003e\\u003c/li\\u003e \\u003cli\\u003e\\u003cspan\\u003eWeinberger MW, Julian TM (1995) Voiding dysfunction and incontinence caused by uterine retroversion: A case report. J Reproductive Med Obstetrician Gynecologist, 40, 5\\u003c/span\\u003e\\u003c/li\\u003e \\u003cli\\u003e\\u003cspan\\u003eFielding WL, Lee SY, Friedman EA (1978) Continued pregnancy after failed first trimester abortion. Obstet Gynecol, 52, 1\\u003c/span\\u003e\\u003c/li\\u003e \\u003cli\\u003e\\u003cspan\\u003eAmso NN et al (2003) Uterine endometrial thermal balloon therapy for the treatment of menorrhagia: Long-term multicentre follow-up study. Hum Reprod 18(5). \\u003cspan class=\\\"ExternalRef\\\"\\u003e\\u003cspan class=\\\"RefSource\\\"\\u003e10.1093/humrep/deg206\\u003c/span\\u003e\\u003cspan address=\\\"10.1093/humrep/deg206\\\" targettype=\\\"DOI\\\" class=\\\"RefTarget\\\"\\u003e\\u003c/span\\u003e\\u003c/span\\u003e\\u003c/span\\u003e\\u003c/li\\u003e \\u003cli\\u003e\\u003cspan\\u003ePEPPERELL RJ, McBAIN JC (1985) Unexplained infertility: a review. BJOG 92(6). \\u003cspan class=\\\"ExternalRef\\\"\\u003e\\u003cspan class=\\\"RefSource\\\"\\u003e10.1111/j.1471-0528.1985.tb01394.x\\u003c/span\\u003e\\u003cspan address=\\\"10.1111/j.1471-0528.1985.tb01394.x\\\" targettype=\\\"DOI\\\" class=\\\"RefTarget\\\"\\u003e\\u003c/span\\u003e\\u003c/span\\u003e\\u003c/span\\u003e\\u003c/li\\u003e \\u003cli\\u003e\\u003cspan\\u003eRomualdi D et al (2023) Evidence-based guideline: unexplained infertility. Hum Reprod 38(10). \\u003cspan class=\\\"ExternalRef\\\"\\u003e\\u003cspan class=\\\"RefSource\\\"\\u003e10.1093/humrep/dead150\\u003c/span\\u003e\\u003cspan address=\\\"10.1093/humrep/dead150\\\" targettype=\\\"DOI\\\" class=\\\"RefTarget\\\"\\u003e\\u003c/span\\u003e\\u003c/span\\u003e\\u003c/span\\u003e\\u003c/li\\u003e \\u003cli\\u003e\\u003cspan\\u003eBOOK REVIEWS, (1982) BJOG 89(5). \\u003cspan class=\\\"ExternalRef\\\"\\u003e\\u003cspan class=\\\"RefSource\\\"\\u003e10.1111/j.1471-0528.1982.tb05088.x\\u003c/span\\u003e\\u003cspan address=\\\"10.1111/j.1471-0528.1982.tb05088.x\\\" targettype=\\\"DOI\\\" class=\\\"RefTarget\\\"\\u003e\\u003c/span\\u003e\\u003c/span\\u003e\\u003c/span\\u003e\\u003c/li\\u003e \\u003cli\\u003e\\u003cspan\\u003eSmalbraak I, Bleker OP, Schutte MF, Treffers PE (1991) Incarceration of the retroverted gravid uterus: a report of four cases. Eur J Obstet Gynecol Reproductive Biology 39(2). \\u003cspan class=\\\"ExternalRef\\\"\\u003e\\u003cspan class=\\\"RefSource\\\"\\u003e10.1016/0028-2243(91)90080-5\\u003c/span\\u003e\\u003cspan address=\\\"10.1016/0028-2243(91)90080-5\\\" targettype=\\\"DOI\\\" class=\\\"RefTarget\\\"\\u003e\\u003c/span\\u003e\\u003c/span\\u003e\\u003c/span\\u003e\\u003c/li\\u003e \\u003cli\\u003e\\u003cspan\\u003eJacobsson B, Wide-Swensson D (1999) Incarceration of the retroverted gravid uterus ‐‐ a review. Acta Obstet Gynecol Scand 78(8). \\u003cspan class=\\\"ExternalRef\\\"\\u003e\\u003cspan class=\\\"RefSource\\\"\\u003e10.1034/j.1600-0412.1999.780801.x\\u003c/span\\u003e\\u003cspan address=\\\"10.1034/j.1600-0412.1999.780801.x\\\" targettype=\\\"DOI\\\" class=\\\"RefTarget\\\"\\u003e\\u003c/span\\u003e\\u003c/span\\u003e\\u003c/span\\u003e\\u003c/li\\u003e \\u003cli\\u003e\\u003cspan\\u003eJordan EC, Murray SM, Brown VA (1976) The retroverted gravid uterus and its effect on the outcome of pregnancy. Br Med J 1(6010). \\u003cspan class=\\\"ExternalRef\\\"\\u003e\\u003cspan class=\\\"RefSource\\\"\\u003e10.1136/bmj.1.6010.622\\u003c/span\\u003e\\u003cspan address=\\\"10.1136/bmj.1.6010.622\\\" targettype=\\\"DOI\\\" class=\\\"RefTarget\\\"\\u003e\\u003c/span\\u003e\\u003c/span\\u003e\\u003c/span\\u003e\\u003c/li\\u003e \\u003cli\\u003e\\u003cspan\\u003eDe Geyter C et al (2018) ART in Europe, 2014: Results generated from European registries by ESHRE. Hum Reprod. \\u003cspan class=\\\"ExternalRef\\\"\\u003e\\u003cspan class=\\\"RefSource\\\"\\u003e10.1093/humrep/dey242\\u003c/span\\u003e\\u003cspan address=\\\"10.1093/humrep/dey242\\\" targettype=\\\"DOI\\\" class=\\\"RefTarget\\\"\\u003e\\u003c/span\\u003e\\u003c/span\\u003e\\u003c/span\\u003e\\u003c/li\\u003e \\u003cli\\u003e\\u003cspan\\u003eDupree JM et al (2019) Provision of insurance coverage for IVF by a large employer and changes in IVF rates among health plan enrollees. JAMA - J Am Med Association 322:19. \\u003cspan class=\\\"ExternalRef\\\"\\u003e\\u003cspan class=\\\"RefSource\\\"\\u003e10.1001/jama.2019.16055\\u003c/span\\u003e\\u003cspan address=\\\"10.1001/jama.2019.16055\\\" targettype=\\\"DOI\\\" class=\\\"RefTarget\\\"\\u003e\\u003c/span\\u003e\\u003c/span\\u003e\\u003c/span\\u003e\\u003c/li\\u003e \\u003cli\\u003e\\u003cspan\\u003eSunderam S et al (2018) Assisted Reproductive Technology Surveillance \\u0026mdash; United States, \\u003cem\\u003eMMWR Surveillance Summaries\\u003c/em\\u003e, vol. 71, no. 4, 2022, \\u003cspan class=\\\"ExternalRef\\\"\\u003e\\u003cspan class=\\\"RefSource\\\"\\u003e10.15585/MMWR.SS7104A1\\u003c/span\\u003e\\u003cspan address=\\\"10.15585/MMWR.SS7104A1\\\" targettype=\\\"DOI\\\" class=\\\"RefTarget\\\"\\u003e\\u003c/span\\u003e\\u003c/span\\u003e\\u003c/span\\u003e\\u003c/li\\u003e \\u003cli\\u003e\\u003cspan\\u003eAgarwal SK, Coe S, Buyalos RP (1994) The influence of uterine position on pregnancy rates with in vitro fertilization-embryo transfer. J Assist Reprod Genet 11(6). \\u003cspan class=\\\"ExternalRef\\\"\\u003e\\u003cspan class=\\\"RefSource\\\"\\u003e10.1007/BF02215722\\u003c/span\\u003e\\u003cspan address=\\\"10.1007/BF02215722\\\" targettype=\\\"DOI\\\" class=\\\"RefTarget\\\"\\u003e\\u003c/span\\u003e\\u003c/span\\u003e\\u003c/span\\u003e\\u003c/li\\u003e \\u003cli\\u003e\\u003cspan\\u003eTissot M, Lecointre L, Faller E, Afors K, Akladios C, Audebert A (2017) Clinical presentation of endometriosis identified at interval laparoscopic tubal sterilization: Prospective series of 465 cases. J Gynecol Obstet Hum Reprod 46(8). \\u003cspan class=\\\"ExternalRef\\\"\\u003e\\u003cspan class=\\\"RefSource\\\"\\u003e10.1016/j.jogoh.2017.05.003\\u003c/span\\u003e\\u003cspan address=\\\"10.1016/j.jogoh.2017.05.003\\\" targettype=\\\"DOI\\\" class=\\\"RefTarget\\\"\\u003e\\u003c/span\\u003e\\u003c/span\\u003e\\u003c/span\\u003e\\u003c/li\\u003e \\u003cli\\u003e\\u003cspan\\u003eMoen MH, Muus KM (1991) Endometriosis in pregnant and non-pregnant women at tubal sterilization. Hum Reprod 6(5). \\u003cspan class=\\\"ExternalRef\\\"\\u003e\\u003cspan class=\\\"RefSource\\\"\\u003e10.1093/oxfordjournals.humrep.a137411\\u003c/span\\u003e\\u003cspan address=\\\"10.1093/oxfordjournals.humrep.a137411\\\" targettype=\\\"DOI\\\" class=\\\"RefTarget\\\"\\u003e\\u003c/span\\u003e\\u003c/span\\u003e\\u003c/span\\u003e\\u003c/li\\u003e \\u003cli\\u003e\\u003cspan\\u003eLalani S et al (2018) Endometriosis and adverse maternal, fetal and neonatal outcomes, a systematic review and meta-analysis. Hum Reprod 33(10). \\u003cspan class=\\\"ExternalRef\\\"\\u003e\\u003cspan class=\\\"RefSource\\\"\\u003e10.1093/humrep/dey269\\u003c/span\\u003e\\u003cspan address=\\\"10.1093/humrep/dey269\\\" targettype=\\\"DOI\\\" class=\\\"RefTarget\\\"\\u003e\\u003c/span\\u003e\\u003c/span\\u003e\\u003c/span\\u003e\\u003c/li\\u003e \\u003cli\\u003e\\u003cspan\\u003eFarland LV et al (2022) Pregnancy outcomes among women with endometriosis and fibroids: registry linkage study in Massachusetts. Am J Obstet Gynecol 226(6). \\u003cspan class=\\\"ExternalRef\\\"\\u003e\\u003cspan class=\\\"RefSource\\\"\\u003e10.1016/j.ajog.2021.12.268\\u003c/span\\u003e\\u003cspan address=\\\"10.1016/j.ajog.2021.12.268\\\" targettype=\\\"DOI\\\" class=\\\"RefTarget\\\"\\u003e\\u003c/span\\u003e\\u003c/span\\u003e\\u003c/span\\u003e\\u003c/li\\u003e \\u003cli\\u003e\\u003cspan\\u003eGlavind K, Bj\\u0026oslash;rk J (2003) Incidence and treatment of urinary retention postpartum. Int Urogynecol J. \\u003cspan class=\\\"ExternalRef\\\"\\u003e\\u003cspan class=\\\"RefSource\\\"\\u003e10.1007/s00192-002-1014-3\\u003c/span\\u003e\\u003cspan address=\\\"10.1007/s00192-002-1014-3\\\" targettype=\\\"DOI\\\" class=\\\"RefTarget\\\"\\u003e\\u003c/span\\u003e\\u003c/span\\u003e\\u003c/span\\u003e\\u003c/li\\u003e\\u003c/ol\\u003e\"},{\"header\":\"Tables\",\"content\":\"\\u003ctable border=\\\"1\\\" cellspacing=\\\"0\\\" cellpadding=\\\"0\\\" width=\\\"98%\\\"\\u003e\\n \\u003ctbody\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd width=\\\"100%\\\" colspan=\\\"4\\\"\\u003e\\n \\u003cp\\u003e\\u003cstrong\\u003eTable 1. Demographic and pregnancy characteristics of nulliparous patients with anteverted vs. retroverted uteri.\\u003c/strong\\u003e\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd width=\\\"46.464646464646464%\\\"\\u003e\\n \\u003cp\\u003e\\u0026nbsp;\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd width=\\\"20.2020202020202%\\\"\\u003e\\n \\u003cp\\u003e\\u003cstrong\\u003eAnteverted uterus\\u003c/strong\\u003e\\u003c/p\\u003e\\n \\u003cp\\u003e\\u003cstrong\\u003en=409\\u003c/strong\\u003e\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd width=\\\"20.2020202020202%\\\"\\u003e\\n \\u003cp\\u003e\\u003cstrong\\u003eRetroverted uterus\\u003c/strong\\u003e\\u003c/p\\u003e\\n \\u003cp\\u003e\\u003cstrong\\u003en= 212\\u003c/strong\\u003e\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd width=\\\"13.131313131313131%\\\"\\u003e\\n \\u003cp\\u003e\\u003cstrong\\u003eP-Value\\u003c/strong\\u003e\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd width=\\\"46.464646464646464%\\\"\\u003e\\n \\u003cp\\u003eMaternal age, years, mean\\u003cu\\u003e+\\u003c/u\\u003eSD\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd width=\\\"20.2020202020202%\\\"\\u003e\\n \\u003cp\\u003e27.46 + 4.77\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd width=\\\"20.2020202020202%\\\"\\u003e\\n \\u003cp\\u003e28.19 + 5.68\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd width=\\\"13.131313131313131%\\\"\\u003e\\n \\u003cp\\u003e0.360\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd width=\\\"46.464646464646464%\\\"\\u003e\\n \\u003cp\\u003eBody Mass Index, kg/m\\u003csup\\u003e2\\u003c/sup\\u003e, mean\\u003cu\\u003e+\\u003c/u\\u003eSD\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd width=\\\"20.2020202020202%\\\"\\u003e\\n \\u003cp\\u003e29.26 + 4.66\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd width=\\\"20.2020202020202%\\\"\\u003e\\n \\u003cp\\u003e29.30 + 5.42\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd width=\\\"13.131313131313131%\\\"\\u003e\\n \\u003cp\\u003e0.872\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd width=\\\"46.464646464646464%\\\"\\u003e\\n \\u003cp\\u003eHx of miscarriage, n (%)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd width=\\\"20.2020202020202%\\\"\\u003e\\n \\u003cp\\u003e97 (23.7)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd width=\\\"20.2020202020202%\\\"\\u003e\\n \\u003cp\\u003e48 (22.6)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd width=\\\"13.131313131313131%\\\"\\u003e\\n \\u003cp\\u003e0.842\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd width=\\\"46.464646464646464%\\\"\\u003e\\n \\u003cp\\u003eIn vitro fertilization, n (%)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd width=\\\"20.2020202020202%\\\"\\u003e\\n \\u003cp\\u003e\\u003cstrong\\u003e28 (6.8)\\u003c/strong\\u003e\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd width=\\\"20.2020202020202%\\\"\\u003e\\n \\u003cp\\u003e\\u003cstrong\\u003e26 (12.3)\\u003c/strong\\u003e\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd width=\\\"13.131313131313131%\\\"\\u003e\\n \\u003cp\\u003e\\u003cstrong\\u003e0.022\\u003c/strong\\u003e\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd width=\\\"46.464646464646464%\\\"\\u003e\\u003cbr\\u003e\\u003c/td\\u003e\\n \\u003ctd width=\\\"20.2020202020202%\\\"\\u003e\\u003cbr\\u003e\\u003c/td\\u003e\\n \\u003ctd width=\\\"20.2020202020202%\\\"\\u003e\\u003cbr\\u003e\\u003c/td\\u003e\\n \\u003ctd width=\\\"13.131313131313131%\\\"\\u003e\\u003cbr\\u003e\\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd width=\\\"46.464646464646464%\\\"\\u003e\\n \\u003cp\\u003eIVF indication, n (%)\\u003c/p\\u003e\\n \\u003cp\\u003eUnexplained\\u003c/p\\u003e\\n \\u003cp\\u003eMale factor\\u003c/p\\u003e\\n \\u003cp\\u003eEndometriosis\\u003c/p\\u003e\\n \\u003cp\\u003ePolycystic ovary syndrome\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd width=\\\"20.2020202020202%\\\"\\u003e\\n \\u003cp\\u003e17 (60.7)\\u003c/p\\u003e\\n \\u003cp\\u003e6 (21.4)\\u003c/p\\u003e\\n \\u003cp\\u003e3 (10.7)\\u003c/p\\u003e\\n \\u003cp\\u003e2 (7.1)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd width=\\\"20.2020202020202%\\\"\\u003e\\n \\u003cp\\u003e16 (61.5)\\u003c/p\\u003e\\n \\u003cp\\u003e6 (23.1)\\u003c/p\\u003e\\n \\u003cp\\u003e3 (11.5)\\u003c/p\\u003e\\n \\u003cp\\u003e1 (3.8)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd width=\\\"13.131313131313131%\\\"\\u003e\\n \\u003cp\\u003e0.961\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd width=\\\"46.464646464646464%\\\"\\u003e\\n \\u003cp\\u003ePre-labor rupture of membranes, n (%)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd width=\\\"20.2020202020202%\\\"\\u003e\\n \\u003cp\\u003e71 (17.4)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd width=\\\"20.2020202020202%\\\"\\u003e\\n \\u003cp\\u003e37 (17.5)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd width=\\\"13.131313131313131%\\\"\\u003e\\n \\u003cp\\u003e1.000\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd width=\\\"46.464646464646464%\\\"\\u003e\\n \\u003cp\\u003eGestational diabetes mellitus, n (%)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd width=\\\"20.2020202020202%\\\"\\u003e\\n \\u003cp\\u003e33 (8.1)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd width=\\\"20.2020202020202%\\\"\\u003e\\n \\u003cp\\u003e14 (6.6)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd width=\\\"13.131313131313131%\\\"\\u003e\\n \\u003cp\\u003e0.51\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd width=\\\"46.464646464646464%\\\"\\u003e\\n \\u003cp\\u003ePreeclampsia, n (%)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd width=\\\"20.2020202020202%\\\"\\u003e\\n \\u003cp\\u003e27 (6.6)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd width=\\\"20.2020202020202%\\\"\\u003e\\n \\u003cp\\u003e20 (9.4)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd width=\\\"13.131313131313131%\\\"\\u003e\\n \\u003cp\\u003e0.21\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd width=\\\"46.464646464646464%\\\"\\u003e\\n \\u003cp\\u003eMiscarriage \\u0026lt; 24 weeks, n (%)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd width=\\\"20.2020202020202%\\\"\\u003e\\n \\u003cp\\u003e4 (1)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd width=\\\"20.2020202020202%\\\"\\u003e\\n \\u003cp\\u003e3 (1.4)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd width=\\\"13.131313131313131%\\\"\\u003e\\n \\u003cp\\u003e0.62\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd width=\\\"46.464646464646464%\\\"\\u003e\\n \\u003cp\\u003ePreterm delivery \\u0026lt; 37 weeks, n (%)\\u003c/p\\u003e\\n \\u003cp\\u003ePreterm delivery \\u0026lt; 32 weeks, n (%)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd width=\\\"20.2020202020202%\\\"\\u003e\\n \\u003cp\\u003e50 (12.2)\\u003c/p\\u003e\\n \\u003cp\\u003e15 (3.7)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd width=\\\"20.2020202020202%\\\"\\u003e\\n \\u003cp\\u003e35 (16.5)\\u003c/p\\u003e\\n \\u003cp\\u003e9 (4.2)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd width=\\\"13.131313131313131%\\\"\\u003e\\n \\u003cp\\u003e0.142\\u003c/p\\u003e\\n \\u003cp\\u003e0.827\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd width=\\\"46.464646464646464%\\\"\\u003e\\n \\u003cp\\u003eBreech presentation, n (%)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd width=\\\"20.2020202020202%\\\"\\u003e\\n \\u003cp\\u003e24 (5.9)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd width=\\\"20.2020202020202%\\\"\\u003e\\n \\u003cp\\u003e14 (6.6)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd width=\\\"13.131313131313131%\\\"\\u003e\\n \\u003cp\\u003e0.576\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd width=\\\"100%\\\" colspan=\\\"4\\\"\\u003e\\n \\u003cp\\u003eSD, standard deviation; n, number.\\u0026nbsp;\\u003c/p\\u003e\\n \\u003cp\\u003eP \\u0026lt; 0.05 was considered significant.\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003c/tbody\\u003e\\n\\u003c/table\\u003e\\n\\u003cp\\u003e\\u0026nbsp;\\u003c/p\\u003e\\n\\u003ctable border=\\\"1\\\" cellspacing=\\\"0\\\" cellpadding=\\\"0\\\" width=\\\"100%\\\"\\u003e\\n \\u003ctbody\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd width=\\\"100%\\\" colspan=\\\"4\\\"\\u003e\\n \\u003cp\\u003e\\u003cstrong\\u003eTable 2.\\u003c/strong\\u003e \\u003cstrong\\u003eComparative maternal and neonatal outcomes in patients with anteverted vs. retroverted uteri attempting vaginal delivery.\\u003c/strong\\u003e\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd width=\\\"54.08163265306123%\\\"\\u003e\\n \\u003cp\\u003e\\u0026nbsp;\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd width=\\\"17.346938775510203%\\\"\\u003e\\n \\u003cp\\u003e\\u003cstrong\\u003eAnteverted uterus\\u003c/strong\\u003e\\u003c/p\\u003e\\n \\u003cp\\u003e\\u003cstrong\\u003en=362\\u003c/strong\\u003e\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd width=\\\"17.346938775510203%\\\"\\u003e\\n \\u003cp\\u003e\\u003cstrong\\u003eRetroverted uterus\\u003c/strong\\u003e\\u003c/p\\u003e\\n \\u003cp\\u003e\\u003cstrong\\u003en= 177\\u003c/strong\\u003e\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd width=\\\"11.224489795918368%\\\"\\u003e\\n \\u003cp\\u003e\\u003cstrong\\u003eP-Value\\u003c/strong\\u003e\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd width=\\\"54.08163265306123%\\\"\\u003e\\n \\u003cp\\u003eGestational age at delivery, weeks, mean +/- S.D.\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd width=\\\"17.346938775510203%\\\"\\u003e\\n \\u003cp\\u003e39 \\u003cu\\u003e+\\u003c/u\\u003e 2.5\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd width=\\\"17.346938775510203%\\\"\\u003e\\n \\u003cp\\u003e38.9 \\u003cu\\u003e+\\u003c/u\\u003e 2.9\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd width=\\\"11.224489795918368%\\\"\\u003e\\n \\u003cp\\u003e0.903\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd width=\\\"54.08163265306123%\\\"\\u003e\\n \\u003cp\\u003eMode of delivery, n (%)\\u003c/p\\u003e\\n \\u003cp\\u003eSpontaneous vaginal delivery\\u003c/p\\u003e\\n \\u003cp\\u003eOperative vaginal delivery\\u003c/p\\u003e\\n \\u003cp\\u003eCesarean delivery\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd width=\\\"17.346938775510203%\\\"\\u003e\\n \\u003cp\\u003e\\u0026nbsp;\\u003c/p\\u003e\\n \\u003cp\\u003e242 (66.9)\\u003c/p\\u003e\\n \\u003cp\\u003e54 (14.9)\\u003c/p\\u003e\\n \\u003cp\\u003e66 (18.2)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd width=\\\"17.346938775510203%\\\"\\u003e\\n \\u003cp\\u003e\\u0026nbsp;\\u003c/p\\u003e\\n \\u003cp\\u003e112 (63.3)\\u003c/p\\u003e\\n \\u003cp\\u003e24 (13.6)\\u003c/p\\u003e\\n \\u003cp\\u003e41 (23.1)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd width=\\\"11.224489795918368%\\\"\\u003e\\n \\u003cp\\u003e\\u0026nbsp;\\u003c/p\\u003e\\n \\u003cp\\u003e0.249\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd width=\\\"54.08163265306123%\\\"\\u003e\\n \\u003cp\\u003eDelivery gestational age, weeks, mean\\u003cu\\u003e+\\u003c/u\\u003eSD\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd width=\\\"17.346938775510203%\\\"\\u003e\\n \\u003cp\\u003e39 \\u003cu\\u003e+\\u003c/u\\u003e 2.5\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd width=\\\"17.346938775510203%\\\"\\u003e\\n \\u003cp\\u003e38.9 \\u003cu\\u003e+\\u003c/u\\u003e 2.9\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd width=\\\"11.224489795918368%\\\"\\u003e\\n \\u003cp\\u003e0.903\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd width=\\\"54.08163265306123%\\\"\\u003e\\n \\u003cp\\u003ePostpartum hemorrhage, n (%)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd width=\\\"17.346938775510203%\\\"\\u003e\\n \\u003cp\\u003e15 (4.1)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd width=\\\"17.346938775510203%\\\"\\u003e\\n \\u003cp\\u003e11 (6.2)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd width=\\\"11.224489795918368%\\\"\\u003e\\n \\u003cp\\u003e0.292\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd width=\\\"54.08163265306123%\\\"\\u003e\\n \\u003cp\\u003eRetained products of conception, n (%)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd width=\\\"17.346938775510203%\\\"\\u003e\\n \\u003cp\\u003e36 (9.9)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd width=\\\"17.346938775510203%\\\"\\u003e\\n \\u003cp\\u003e22 (12.4)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd width=\\\"11.224489795918368%\\\"\\u003e\\n \\u003cp\\u003e0.379\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd width=\\\"54.08163265306123%\\\"\\u003e\\n \\u003cp\\u003eBirthweight at delivery, grams, mean\\u003cu\\u003e+\\u003c/u\\u003eSD\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd width=\\\"17.346938775510203%\\\"\\u003e\\n \\u003cp\\u003e3128.2 \\u003cu\\u003e+\\u003c/u\\u003e 547\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd width=\\\"17.346938775510203%\\\"\\u003e\\n \\u003cp\\u003e3083.3 \\u003cu\\u003e+\\u003c/u\\u003e 643\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd width=\\\"11.224489795918368%\\\"\\u003e\\n \\u003cp\\u003e0.578\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd width=\\\"54.08163265306123%\\\"\\u003e\\n \\u003cp\\u003eBirthweight at delivery \\u0026lt; 2,500 g, n (%)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd width=\\\"17.346938775510203%\\\"\\u003e\\n \\u003cp\\u003e33 (9.1)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd width=\\\"17.346938775510203%\\\"\\u003e\\n \\u003cp\\u003e17 (9.6)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd width=\\\"11.224489795918368%\\\"\\u003e\\n \\u003cp\\u003e0.875\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd width=\\\"54.08163265306123%\\\"\\u003e\\n \\u003cp\\u003eApgar score at 5 min \\u0026lt; 7, n (%)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd width=\\\"17.346938775510203%\\\"\\u003e\\n \\u003cp\\u003e8 (2.2)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd width=\\\"17.346938775510203%\\\"\\u003e\\n \\u003cp\\u003e3 (1.7)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd width=\\\"11.224489795918368%\\\"\\u003e\\n \\u003cp\\u003e1.00\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd width=\\\"54.08163265306123%\\\"\\u003e\\n \\u003cp\\u003eAdmission to NICU, n (%)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd width=\\\"17.346938775510203%\\\"\\u003e\\n \\u003cp\\u003e16 (4.4)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd width=\\\"17.346938775510203%\\\"\\u003e\\n \\u003cp\\u003e12 (6.8)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd width=\\\"11.224489795918368%\\\"\\u003e\\n \\u003cp\\u003e0.302\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd width=\\\"100%\\\" colspan=\\\"4\\\"\\u003e\\n \\u003cp\\u003en, number; NICU, neonatal intensive care unit.\\u0026nbsp;\\u003c/p\\u003e\\n \\u003cp\\u003eP \\u0026lt; 0.05 was considered significant.\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003c/tbody\\u003e\\n\\u003c/table\\u003e\"}],\"fulltextSource\":\"\",\"fullText\":\"\",\"funders\":[],\"hasAdminPriorityOnWorkflow\":false,\"hasManuscriptDocX\":true,\"hasOptedInToPreprint\":true,\"hasPassedJournalQc\":\"\",\"hasAnyPriority\":false,\"hideJournal\":true,\"highlight\":\"\",\"institution\":\"\",\"isAcceptedByJournal\":false,\"isAuthorSuppliedPdf\":false,\"isDeskRejected\":\"\",\"isHiddenFromSearch\":false,\"isInQc\":false,\"isInWorkflow\":false,\"isPdf\":false,\"isPdfUpToDate\":true,\"isWithdrawnOrRetracted\":false,\"journal\":{\"display\":true,\"email\":\"info@researchsquare.com\",\"identity\":\"researchsquare\",\"isNatureJournal\":false,\"hasQc\":true,\"allowDirectSubmit\":true,\"externalIdentity\":\"\",\"sideBox\":\"\",\"snPcode\":\"\",\"submissionUrl\":\"/submission\",\"title\":\"Research Square\",\"twitterHandle\":\"researchsquare\",\"acdcEnabled\":true,\"dfaEnabled\":false,\"editorialSystem\":\"\",\"reportingPortfolio\":\"\",\"inReviewEnabled\":false,\"inReviewRevisionsEnabled\":true},\"keywords\":\"Retroverted uterus, anteverted uterus, spontaneous pregnancy, trial of labor, pregnancy\",\"lastPublishedDoi\":\"10.21203/rs.3.rs-4400217/v1\",\"lastPublishedDoiUrl\":\"https://doi.org/10.21203/rs.3.rs-4400217/v1\",\"license\":{\"name\":\"CC BY 4.0\",\"url\":\"https://creativecommons.org/licenses/by/4.0/\"},\"manuscriptAbstract\":\"\\u003ch2\\u003ePurpose\\u003c/h2\\u003e \\u003cp\\u003eRetroverted uterus affects 15\\u0026ndash;20% of patients. While typically not a cause for concern, some studies suggest a relationship between a retroverted uterus and subfertility. Study objective was to investigate the association between uterine position and spontaneous conception rates, as well as potential risks for adverse pregnancy outcomes in nulliparous patients.\\u003c/p\\u003e\\u003ch2\\u003eMethods\\u003c/h2\\u003e \\u003cp\\u003e We analyzed data from a retrospective cohort study of 621 nulliparous patients with confirmed pregnancies who received prenatal care at a large medical center between 2006 and 2022. Ultrasound exams documented their uterine position at the beginning of pregnancy. Women were categorized into two groups according to their uterine position. We compared the groups regarding mode of conception (spontaneous/ IVF), pregnancy complications, and vaginal delivery outcomes.\\u003c/p\\u003e\\u003ch2\\u003eResults\\u003c/h2\\u003e \\u003cp\\u003eCompared to patients with anteverted uteri, those with retroverted uteri had a significantly higher rate of conception through IVF (12.3% vs. 6.8%, p\\u0026thinsp;=\\u0026thinsp;0.022). IVF indications were similar between groups (p\\u0026thinsp;=\\u0026thinsp;0.961). Pregnancy complications, including pre-labor rupture of membranes, miscarriages, and preterm delivery\\u0026thinsp;\\u0026lt;\\u0026thinsp;37 and \\u0026lt;\\u0026thinsp;32 weeks\\u0026rsquo;, were similar. Breech presentation at delivery was comparable between cohorts (~\\u0026thinsp;6%, p\\u0026thinsp;=\\u0026thinsp;0.576). Among patients attempting vaginal delivery (n\\u0026thinsp;=\\u0026thinsp;539), cesarean delivery rates were comparable (18.2% anteverted vs. 23.1% retroverted, p\\u0026thinsp;=\\u0026thinsp;0.249). No significant differences were observed in other maternal or neonatal outcomes between the groups.\\u003c/p\\u003e\\u003ch2\\u003eConclusion\\u003c/h2\\u003e \\u003cp\\u003eThis study contributes valuable insights into the potential influence of uterine position on pregnancy. While a retroverted uterus does not seem to be a significant risk factor for adverse outcomes, the observed trend regarding its association with IVF pregnancies necessitates further investigation.\\u003c/p\\u003e\",\"manuscriptTitle\":\"The impact of uterine position on conception modes and perinatal outcomes in nulliparous patients.\",\"msid\":\"\",\"msnumber\":\"\",\"nonDraftVersions\":[{\"code\":1,\"date\":\"2024-06-26 14:57:02\",\"doi\":\"10.21203/rs.3.rs-4400217/v1\",\"editorialEvents\":[{\"type\":\"communityComments\",\"content\":0}],\"status\":\"published\",\"journal\":{\"display\":true,\"email\":\"info@researchsquare.com\",\"identity\":\"researchsquare\",\"isNatureJournal\":false,\"hasQc\":true,\"allowDirectSubmit\":true,\"externalIdentity\":\"\",\"sideBox\":\"\",\"snPcode\":\"\",\"submissionUrl\":\"/submission\",\"title\":\"Research Square\",\"twitterHandle\":\"researchsquare\",\"acdcEnabled\":true,\"dfaEnabled\":false,\"editorialSystem\":\"\",\"reportingPortfolio\":\"\",\"inReviewEnabled\":false,\"inReviewRevisionsEnabled\":true}}],\"origin\":\"\",\"ownerIdentity\":\"1e2689ca-c674-479d-9016-53e85a591fd0\",\"owner\":[],\"postedDate\":\"June 26th, 2024\",\"published\":true,\"recentEditorialEvents\":[],\"rejectedJournal\":[],\"revision\":\"\",\"amendment\":\"\",\"status\":\"posted\",\"subjectAreas\":[],\"tags\":[],\"updatedAt\":\"2024-09-23T19:46:37+00:00\",\"versionOfRecord\":[],\"versionCreatedAt\":\"2024-06-26 14:57:02\",\"video\":\"\",\"vorDoi\":\"\",\"vorDoiUrl\":\"\",\"workflowStages\":[]},\"version\":\"v1\",\"identity\":\"rs-4400217\",\"journalConfig\":\"researchsquare\"},\"__N_SSP\":true},\"page\":\"/article/[identity]/[[...version]]\",\"query\":{\"redirect\":\"/article/rs-4400217\",\"identity\":\"rs-4400217\",\"version\":[\"v1\"]},\"buildId\":\"qtupq5eGEP_6zYnWcrvyt\",\"isFallback\":false,\"isExperimentalCompile\":false,\"dynamicIds\":[84888],\"gssp\":true,\"scriptLoader\":[]}","source_license":"CC-BY-4.0","license_restricted":false}