Morbidity of Repeat Cesarean Delivery after a Trial of Labor as Compared with Elective Repeat Cesarean Delivery.

OBJECTIVE: This study aimed to evaluate if a secondary repeat cesarean after a trial of labor (TOLAC) without uterine rupture is associated with increased morbidity as compared with a scheduled elective repeat cesarean delivery (ERCD). STUDY DESIGN: This was a retrospective cohort study of repeat cesarean delivery (CD) in a single obstetrical practice between 2005 and 2022. Patients were included if they had a singleton pregnancy at term with one prior CD and had a repeat CD this pregnancy resulting in live birth. Patients were excluded if they had a prior myomectomy, more than one prior CD, uterine rupture in a prior or current pregnancy, or placenta previa in this pregnancy. We compared baseline characteristics and outcomes between patients who had a repeat cesarean after TOLAC and ERCD. The primary outcome was a composite of maternal morbidity that included hysterectomy, blood transfusion, cystotomy, bowel injury, intensive care unit admission, thrombosis, reoperation, or maternal mortality. RESULTS: A total of 930 women met inclusion criteria. A total of 176 (18.9%) patients intended to labor and 754 (81.1%) planned an ERCD. There was no difference in the primary outcome between patients with a repeat cesarean after TOLAC compared with patients with ERCD (2.8 vs. 1.2%, p = 0.158). Patients with repeat cesarean after labor had significantly more 1-minute Apgar scores less than 7, but no difference in 5-minute Apgar scores. We were powered to detect a difference in the primary outcome from 1.2% in the ERCD group to 3.3% in the repeat cesarean after labor group. Results did not differ when we analyzed patients who intended to TOLAC versus patients who actually labored prior CD. CONCLUSION: For women with one prior CD the morbidity of repeat cesarean after labor is not more than the morbidity of planned repeat CD. Our study can be helpful in delivery planning counseling for patients with one prior CD. KEY POINTS: · Uterine rupture is a known risk of TOLAC.. · This study aimed to understand morbidity associated with labor.. · No added morbidity of repeat cesarean after labor is inferred in this study..

Is Increasing Parity Associated with Adverse Perinatal Outcomes in Dichorionic Twin Gestations?

OBJECTIVE: Dichorionic twins have increased risk of preterm birth and hypertensive disorders of pregnancy. Grand multiparity may be associated with adverse perinatal outcomes in singleton pregnancies, although the effect of increasing parity in twins is unclear. This study aimed to elucidate whether grand multiparity leads to adverse outcomes in dichorionic twins compared with multiparity and nulliparity. STUDY DESIGN: This was a retrospective review of dichorionic twins at a single institution between January 2008 and December 2019 comparing pregnancy outcomes among grand multiparity, multiparity, and nulliparity. Primary outcome was preterm birth less than 37 weeks. Multivariable regression controlled for differing demographics, prior preterm birth, use of reproductive technologies, and hypertensive disorders of pregnancy. Chi square and Fisher's exact were used for categorical variables and Kruskal-Wallis was used for continuous variables. RESULTS: A total of 843 (60.3%) pregnancies were nulliparous, 499 (35.7%) multiparous, and 57(4.1%) grand multiparous. Univariate analysis indicated that multiparous women had lower incidence of preterm birth less than 37, 34, and 32 weeks (57 vs. 51%, p = 0.04; 19.2 vs. 14.0%, p = 0.02; 9.6 vs. 5.6%, p = 0.01) and that grand multiparous women had lower incidence of preterm birth less than 34 weeks (19.2 vs. 5.3%, p = 0.008) compared with nulliparous women. Multivariable regression confirmed multiparous women had lower odds of preterm birth less than 34 and 32 weeks compared with nulliparous women (<34 wk: odds ratio [OR] = 0.69, 95% confidence interval [CI] = 0.49-0.97, p = 0.03; <32 wk: OR = 0.48, 95% CI = 0.29-0.79, p = 0.004) and that multiparous women (OR = 0.57, 95% CI = 0.42-0.77, p = 0.0002) and grand multiparous women (OR = 0.23, 95% CI = 0.08-0.68, p = 0.0074) had lower incidence of hypertensive disorders of pregnancy when compared with nulliparous women. CONCLUSION: Grand multiparity is not associated with adverse perinatal outcomes compared with nulliparity or multiparity in dichorionic twins. Increasing parity may protect against incidence of preterm birth and hypertensive disorders of pregnancy even among grand multiparous women. KEY POINTS: · Incidence of preterm birth may decrease with increasing parity in twins.. · Hypertensive disorders of pregnancy may decrease with increasing parity in twins.. · Grand multiparity is not associated with adverse perinatal outcomes in twins..

National and international guidelines on the management of twin pregnancies: a comparative review.

Twin gestations are associated with increased risk of pregnancy complications. However, high-quality evidence regarding the management of twin pregnancies is limited, often resulting in inconsistencies in the recommendations of various national and international professional societies. In addition, some recommendations related to the management of twin gestations are often missing from the clinical guidelines dedicated to twin pregnancies and are instead included in the practice guidelines on specific pregnancy complications (eg, preterm birth) of the same professional society. This can make it challenging for care providers to easily identify and compare recommendations for the management of twin pregnancies. This study aimed to identify, summarize, and compare the recommendations of selected professional societies from high-income countries on the management of twin pregnancies, highlighting areas of both consensus and controversy. We reviewed clinical practice guidelines of selected major professional societies that were either specific to twin pregnancies or were focused on pregnancy complications or aspects of antenatal care that may be relevant for twin pregnancies. We decided a priori to include clinical guidelines from 7 high-income countries (United States, Canada, United Kingdom, France, Germany, and Australia and New Zealand grouped together) and from 2 international societies (International Society of Ultrasound in Obstetrics and Gynecology and the International Federation of Gynecology and Obstetrics). We identified recommendations regarding the following care areas: first-trimester care, antenatal surveillance, preterm birth and other pregnancy complications (preeclampsia, fetal growth restriction, and gestational diabetes mellitus), and timing and mode of delivery. We identified 28 guidelines published by 11 professional societies from the 7 countries and 2 international societies. Thirteen of these guidelines focus on twin pregnancies, whereas the other 16 focus on specific pregnancy complications predominantly in singletons but also include some recommendations for twin pregnancies. Most of the guidelines are recent, with 15 of the 29 guidelines published over the past 3 years. We identified considerable disagreement among guidelines, primarily in 4 key areas: screening and prevention of preterm birth, using aspirin to prevent preeclampsia, defining fetal growth restriction, and the timing of delivery. In addition, there is limited guidance on several important areas, including the implications of the "vanishing twin" phenomenon, technical aspects and risks of invasive procedures, nutrition and weight gain, physical and sexual activity, the optimal growth chart to be used in twin pregnancies, the diagnosis and management of gestational diabetes mellitus, and intrapartum care.This consolidation of key recommendations across several clinical practice guidelines can assist healthcare providers in accessing and comparing recommendations on the management of twin pregnancies and identifies high-priority areas for future research based on either continued disagreement among societies or limited current evidence to guide care.

Association Between Mental Health and Reproductive System Disorders in Women: A Systematic Review and Meta-analysis.

Importance: Reproductive system and mental health disorders are commonly comorbid in women. Although the causes of this overlap remain elusive, evidence suggests potential shared environmental and genetic factors associated with risk. Objective: To investigate the comorbidity between psychiatric and reproductive system disorders, both as broad diagnostic categories and among specific pairs of diagnoses. Data Source: PubMed. Study Selection: Observational studies published between January 1980 and December 2019 assessing prevalence of psychiatric disorders in women with reproductive system disorders and prevalence of reproductive system disorders in women with psychiatric disorders were included. The study did not include psychiatric and reproductive disorders triggered by life events (eg, trauma, infection, surgery) to address potential confounding. Data Extraction and Synthesis: A search yielded 1197 records, of which 50 met the inclusion criteria for the qualitative and 31 for the quantitative synthesis in our study. A random-effects model was used for data synthesis and Egger test and I2 to assess study bias and heterogeneity. Data were analyzed from January to December 2022. This study followed the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guideline. Main Outcomes and Measures: Psychiatric and reproductive system disorders. Results: A total of 1197 records were identified, of which 50 met the inclusion criteria for qualitative and 31 for quantitative synthesis. Diagnosis of a reproductive system disorder was associated with a 2- to 3-fold increased odds of having a psychiatric disorder (lower bound odds ratio [OR], 2.00; 95% CI, 1.41-2.83; upper bound OR; 2.88; 95% CI, 2.21-3.76). The analysis focused on specific diagnoses described in the literature and found that polycystic ovary syndrome was associated with increased odds of depression (population-based studies OR, 1.71; 95% CI, 1.19-2.45; clinical studies OR, 2.58; 95% CI, 1.57-4.23) and anxiety (population-based studies OR, 1.69; 95% CI, 1.36-2.10; clinical studies OR, 2.85; 95% CI, 1.98-4.09). Chronic pelvic pain was also associated with both depression (OR, 3.91; 95% CI, 1.81-8.46) and anxiety (OR, 2.33; 95% CI, 1.33-4.08). Few studies investigated risk of other reproductive system disorders in women with psychiatric disorders, or reverse associations (risk of reproductive system disorder among women with a psychiatric diagnosis). Conclusions and Relevance: In this systematic review and meta-analysis, a high rate of reported co-occurrence between psychiatric and reproductive disorders overall was observed. However, data for many disorder pairs were limited. The available literature focused overwhelmingly on affective disorders in polycystic ovary syndrome, overlooking a substantial portion of disease overlap. As such, the associations between the majority of mental health outcomes and conditions of the female reproductive system are largely unknown.

Outcomes of Elective Compared to Non-Elective Fetal Reduction by Radiofrequency Ablation in Monochorionic Multifetal Pregnancies.

INTRODUCTION: Higher order fetal gestation is associated with adverse pregnancy outcomes, and monochorionic (MC) pregnancies have unique complications. Multifetal pregnancy reduction (MPR) by radiofrequency ablation (RFA) may be used to optimize the outcomes of a single fetus. The purpose of this study was to determine whether pregnancy outcomes differ for elective reduction compared to reduction for medically complicated MC multifetal pregnancies. METHODS: This was a retrospective cohort of patients with MC twins and higher order multiples who underwent MPR via RFA at a single institution between 2008 and 2021. Patients undergoing elective reduction were compared to patients undergoing reduction due to a complication of MC pregnancy. Pregnancy outcomes were evaluated. RESULTS: Forty-eight patients who underwent RFA reduction between 2008 and 2021 were included in the analysis. Sixteen patients (33.3%) underwent elective RFA for MPR, and 32 (66.7%) underwent an RFA procedure for a complicated pregnancy. All pregnancies with RFA performed for elective indication had a continuing pregnancy (live birth rate 100%). There were no reported pregnancy losses within 4 weeks of the procedure when performed for a solely elective indication (n = 0) compared to 6.3% of complicated multifetal pregnancy (n = 2; 6.3%) (p = 0.001). CONCLUSION: In this retrospective cohort study, elective reduction of MC twins using RFA was associated with no cases of fetal loss or PPROM within 4 weeks of the procedure and a 100% live birth rate.

Maternal Morbidity with Repeated Cesarean Deliveries.

OBJECTIVE: This study aimed to estimate the association between adverse maternal outcomes and the number of repeated cesarean deliveries (CDs) in a single obstetrical practice. STUDY DESIGN: Retrospective cohort study of all CDs between 2005 and 2020 in a single maternal fetal medicine practice. We used electronic records to get baseline characteristics and pregnancy/surgical outcomes based on the number of prior CDs. We performed two subgroup analyses for women with and without placenta previa. Chi-square for trend and one-way analysis of variance (ANOVA) were used. RESULTS: A total of 3,582 women underwent CD and met inclusion criteria. Of these women, 1,852 (51.7%) underwent their first cesarean, 950 (26.5%) their second, 382 (10.7%) their third, 191 (5.3%) their fourth, 117 (3.3%) their fifth, and 84 (2.3%) their sixth or higher CDs. The incidence of adverse outcomes (placenta accreta, uterine window, uterine rupture, hysterectomy, blood transfusion, cystotomy, bowel injury, need for a ventilator postpartum, intensive care unit admission, wound complications, thrombosis, reoperation, and maternal death) increased with additional CDs. However, the absolute rates remained low. In women without a placenta previa, the likelihood of adverse outcome did not differ across groups. In women with a placenta previa, adverse outcomes increased with increasing CDs. However, the incidence of placenta previa did not increase with increasing CDs (<5% in each group). The incidence of a uterine dehiscence increased significantly with additional CDs: first, 0.2%; second, 2.0%; third, 6.6%; fourth, 10.3%; fifth, 5.8%; and sixth or higher, 10.4% (p < 0.001). CONCLUSION: Maternal morbidity increases with CDs, but the absolute risks remain low. For women without placenta previa, increasing CDs is not associated with maternal morbidity. For women with placenta previa, risks are highest, but the incidence of placenta previa does not increase with successive CDs. The likelihood of uterine dehiscence increases significantly with increasing CDs which should be considered when deciding about timing of delivery in this population. KEY POINTS: · Maternal morbidity increase with each CD.. · Absolute adverse outcomes remains low in highest order CDs.. · In women without placenta previa, there is no added morbidity with additional CDs..

Trial of labor of vertex-nonvertex twins following a previous cesarean delivery.

BACKGROUND: Maternal and neonatal outcomes of trial of labor after cesarean delivery of twins are similar to those of singleton trials of labor after cesarean delivery. However, previous studies did not stratify outcomes by second-twin presentation on admission to labor. OBJECTIVE: To examine maternal and neonatal outcomes following trial of labor after cesarean delivery in twins with vertex-nonvertex presentation. STUDY DESIGN: A retrospective multicenter study was conducted including data on deliveries occurring between the years 2005 and 2020. We included trials of labor after a previous cesarean delivery (at ≥320/7 weeks' gestation) of twin gestations with a vertex-presenting first twin on admission to labor. The exposed group was defined as deliveries with a nonvertex second twin at admission to labor, whereas the comparison group included deliveries with a vertex second twin at admission. Only parturients who attempted vaginal delivery were included. Cases of prelabor fetal death of either twin or major fetal anomalies were excluded. The primary outcome was uterine rupture. RESULTS: A total of 236 twin trials of labor after cesarean delivery were included, of which 128 involved nonvertex second twins and 108 a second vertex twin. Uterine rupture rates were comparable between the groups (1/128 [0.9%] vs 1/108 [0.8%]; P=1.000). Successful trial of labor after cesarean delivery of both twins occurred in 76.6% of the exposed group vs 81.5% of the comparison group, whereas cesarean delivery of both twins was performed in 21.9% of the exposed group vs 17.6% of the comparison group (P=.418; odds ratio, 1.32; confidence interval, 0.7-2.5). Two cases of cesarean delivery of the second twin occurred in the exposed group and 1 in the comparison group (1.6% vs 0.9%, respectively, P=1.000). There was no difference between the groups in maternal outcomes, including rates of postpartum hemorrhage, blood transfusion, placental abruption, thromboembolic events, and maternal fever. Neonatal outcomes were also comparable between the groups, including rates of intensive care admission and low (≤7) 5-minute Apgar scores. CONCLUSION: Our data show that trial of labor after cesarean delivery of noncephalic second twins holds favorable maternal and neonatal outcomes, comparable with those of vertex-vertex trials of labor after cesarean delivery. Second-twin noncephalic presentation should not discourage parturients and caregivers from considering trial of labor after cesarean delivery if desired.

Should twin-specific growth charts be used to assess fetal growth in twin pregnancies?

One of the hallmarks of twin pregnancies is the slower rate of fetal growth when compared with singleton pregnancies during the third trimester. The mechanisms underlying this phenomenon and whether it represents pathology or benign physiological adaptation are currently unclear. One important implication of these questions relates to the type growth charts that should be used by care providers to monitor growth of twin fetuses. If the slower growth represents pathology (ie, intrauterine growth restriction caused uteroplacental insufficiency), it would be preferable to use a singleton growth chart to identify a small twin fetus that is at risk for perinatal mortality and morbidity. If, however, the relative smallness of twins is the result of benign adaptive mechanisms, it is likely preferable to use a twin-based charts to avoid overdiagnosis of intrauterine growth restriction in twin pregnancies. In the current review, we addressed this question by describing the differences in fetal growth between twin and singleton pregnancies, reviewing the current knowledge regarding the mechanisms responsible for slower fetal growth in twins, summarizing available empirical evidence on the diagnostic accuracy of the 2 types of charts for intrauterine growth restriction in twin pregnancies, and addressing the question of whether uncomplicated dichorionic twins are at an increased risk for fetal death when compared with singleton fetuses. We identified a growing body of evidence that shows that the use of twin charts can reduce the proportion of twin fetuses identified with suspected intrauterine growth restriction by up to 8-fold and can lead to a diagnosis of intrauterine growth restriction that is more strongly associated with adverse perinatal outcomes and hypertensive disorders than a diagnosis of intrauterine growth restriction based on a singleton-based chart without compromising the detection of twin fetuses at risk for adverse outcomes caused by uteroplacental insufficiency. We further found that small for gestational age twins are less likely to experience adverse perinatal outcomes or to have evidence of uteroplacental insufficiency than small for gestational age singletons and that recent data question the longstanding view that uncomplicated dichorionic twins are at an increased risk for fetal death caused by placental insufficiency. Overall, it seems that, based on existing evidence, the of use twin charts is reasonable and may be preferred over the use of singleton charts when monitoring the growth of twin fetuses. Still, it is important to note that the available data have considerable limitations and are primarily derived from observational studies. Therefore, adequately-powered trials are likely needed to confirm the benefit of twin charts before their use is adopted by professional societies.

Stratified risk of pregnancy loss for women with a viable singleton pregnancy in the first trimester.

OBJECTIVE: Calculate the risk of miscarriage in women with a viable (defined as presence of fetal heart rate on ultrasound) first trimester singleton pregnancy and to create a model for stratified risk-assessment for pregnancy loss based on significant risk factors. STUDY DESIGN: Retrospective cohort study of unselected women with singleton pregnancies in a large obstetrical practice who presented for prenatal care prior to 14 weeks over a three-year period. All women underwent a formal first-trimester ultrasound, and we only included women with viable pregnancies with fetal heart activity seen on that ultrasound. Our primary outcome was pregnancy loss prior to 20 weeks. Statistical modeling was used to create a risk-assessment tool from adjusted likelihood ratios of pregnancy loss based on risk factors independently associated with this outcome. RESULTS: From January 2015-December 2017, 2,446 women met the inclusion criteria for the study and 132 (5.4%) had a pregnancy loss <20 weeks. On regression analysis, the independent risk factors for pregnancy loss were earlier gestational age (aOR 0.72, 95% CI 0.65-0.80) and increasing number of prior miscarriages (aOR 1.56, 95% CI 1.32-1.83). Using these risk factors, we calculated the stratified risk of pregnancy loss, which ranged from 0.8% in women at 13 weeks of gestation with no prior miscarriages to 33.7% in women at six weeks of gestation with three or more prior miscarriages. CONCLUSION: In first trimester singleton pregnancies, the overall risk of pregnancy loss <20 weeks after confirmation of fetal heart activity is 5.4%, but can be stratified for each woman and ranges from 0.8% to 33.7% based on the gestational age and number of prior pregnancy losses.

The association between sonographic cervical length components and preterm birth in women with ultrasound- or exam-indicated cerclage.

OBJECTIVE: To evaluate which parameters of a sonographic cervical length measurement are associated with preterm birth in women with ultrasound- or exam-indicated cerclage. METHODS: This was a retrospective cohort study of women with singleton pregnancies who underwent ultrasound- or exam-indicated Shirodkar cerclage by a single maternal-fetal medicine practice between 2011 and 2019. All patients underwent sonographic cervical length measurement 2-3 weeks after cerclage placement, and then every 2-4 weeks up to 32 weeks. The images from the first and second post-cerclage cervical lengths were reviewed. Total cervical length, upper cervical length (from the internal cervical os to the cerclage), and lower cervical length (from the cerclage to the external os) were measured. The primary outcome for this study was gestational age at delivery. RESULTS: A total of 114 women with cerclage were included (85 (74.6%) ultrasound-indicated and 29 (25.4%) exam-indicated). The first and second total cervical lengths correlated with gestational age at delivery (r = 0.26, p=.005; r = 0.33, p<.001, respectively), and the change from first to second was inversely correlated with gestational age at delivery (r = -0.20, p=.032). The first and second upper cervical lengths also correlated with gestational age at delivery (r = 0.22, p = .019; r = 0.33, p<.001, respectively), and the change from first to second upper cervical length was inversely correlated with gestational age at delivery (r= -0.20, r = 0.029). Neither the first nor the second lower cervical lengths were significantly associated with gestational age at delivery. On regression analysis, total cervical length and upper cervical length were not independently associated with gestational age at delivery (p = .108 and p=.806, respectively, for the first scan; p = .153 and p=.166, respectively, for the second scan). CONCLUSIONS: Postcerclage total cervical length and upper cervical length are both associated with gestational age at delivery and risk of preterm birth, but not independently. After ultrasound- or exam-indicated cerclage, sonographic monitoring of either the total cervical length or the upper cervical length might be predictive of gestational age at delivery and the risk of preterm birth.

Incidence and Risk Factors for a Malpositioned Intrauterine Device Detected on Three-Dimensional Ultrasound Within Eight Weeks of Placement.

OBJECTIVES: To estimate the incidence of intrauterine device (IUD) malpositioning detected on three-dimensional (3D) transvaginal ultrasound within 8 weeks of placement and identify risk factors for malpositioning. METHODS: Retrospective study of women who had an IUD placed at a large obstetrics and gynecology practice from January 1, 2015, to December 31, 2020. All patients underwent two-dimensional ultrasound at the time of insertion and routine three-dimensional ultrasound within 8 weeks. Baseline characteristics and potential risk factors were compared between women with correctly positioned and malpositioned IUDs. Odds ratios were calculated by logistic regression to identify risk factors independently associated with malpositioning. RESULTS: A total of 763 IUD placements were included, and 127 malpositioned IUDs were identified representing an overall rate of malpositioning of 16.6% (95% confidence interval [CI] 14.0-19.3) with 8.8% (95% CI 6.8-10.8) requiring removal. Patients with malpositioned IUD had higher rates of morbid obesity (13.4% versus 3.8%, adjusted odds ratio [aOR] 2.46, 95% CI 1.10-5.50), prior uterine window or rupture (9.0% versus 2.2%, aOR 2.78, 95% CI 1.06-7.30), copper IUD placement (64.2% versus 47.4%, aOR 1.99, 95% CI 1.31-3.03), and symptoms such as bleeding or pain at follow-up (35.8% versus 20.1%, aOR 2.58, 95% CI 1.67-3.98). Parity, breastfeeding, difficult insertion, and uterine size and positioning were not significant. CONCLUSIONS: The incidence of malpositioned IUD within 8 weeks of placement on 3D ultrasound is 16.6%, with 8.8% requiring removal. Significant risk factors for malpositioning include morbid obesity, prior uterine window or rupture, and copper IUD placement. These findings support the importance of routine follow-up 3D ultrasound after seemingly successful IUD placement.

Screening for preterm birth in twin pregnancies.

Twins represent 3.2% of all live births. However, they account for 20% of all preterm deliveries, with 60% delivered before 37 weeks and 10.7% before 32 weeks of gestation. Twin pregnancies have a 5 times higher risk of early neonatal and infant death related to prematurity. Monochorionic twins have a higher incidence of both indicated and spontaneous preterm delivery than dichorionic twins. Additional risk factors include a history of preterm delivery and cervical surgery. The transvaginal cervical length before 24 weeks is the best factor to predict preterm birth, independent of other risk factors.

Prevention of preterm birth in twin pregnancies.

Twins represent 3.2% of all live births; however, they account for 20.0% of all preterm deliveries, with 60.0% and 10.7% of twins delivered before 37 and 32 weeks' gestation, respectively. Twin pregnancies have 5 times higher risk of early neonatal and infant death related to prematurity. Monochorionic twins have a higher incidence of both indicated and spontaneous preterm delivery than dichorionic twins. Transvaginal ultrasound of the cervical length before 24 weeks' gestation is the best tool to predict preterm birth, independent of other risk factors. Among all evaluated therapies to decrease or prevent preterm birth in twin pregnancies, the use of vaginal progesterone in women with a transvaginal cervical length of <25 mm decreased neonatal morbidity, and physical examination-indicated cerclage in women with a cervical dilation of >1 cm showed a significant decrease in preterm birth at different gestational ages and perinatal mortality.

Arcuate Uterus as an Independent Risk Factor for Adverse Pregnancy Outcomes.

OBJECTIVE: The aim of the study is to estimate the association between arcuate uterus and pregnancy outcomes using controls selected from a similarly high-risk cohort. STUDY DESIGN: This is a retrospective cohort study of women with an arcuate uterus cared for by a single maternal-fetal medicine practice from 2005 to 2020. We included all women with a singleton pregnancy ≥20 weeks and diagnosis of arcuate uterus and randomly selected (3:1) patients with a singleton pregnancy and no uterine anomaly from the same practice as controls. Baseline characteristics and pregnancy outcomes were compared between the two groups. Chi-square, Fisher's exact, and independent samples t-test were used for data analysis, as indicated. RESULTS: A total of 37 women with an arcuate uterus (55 independent singleton pregnancies) and 165 controls were included. There were no differences in baseline characteristics. Women with an arcuate uterus had a significantly higher rate of spontaneous preterm birth less than 37 weeks (10.9 vs. 3.0%, p = 0.031) and were more likely to require vaginal progesterone (5.5 vs. 0.6%, p = 0.049) and administration of antenatal corticosteroids (16.4 vs. 5.5%, p = 0.020). Arcuate uterus was also associated with lower birthweight (3,028.1 ± 528.0 vs. 3257.2 ± 579.9 g, p = 0.010) and higher incidence of intrauterine fetal growth restriction (20.0 vs. 7.3%, p = 0.008), despite similar starting body mass index (BMI) and weight gain throughout pregnancy. There were no differences in preeclampsia, malpresentation, cesarean delivery, blood transfusion, retained placenta, or morbidly adherent placenta. CONCLUSION: Arcuate uterus is associated with a significantly increased risk of spontaneous preterm birth (<37 weeks), need for vaginal progesterone for short cervix and antenatal corticosteroids, fetal growth restriction, and lower mean birthweight. These findings suggest that arcuate uterus is not just a normal variant of uterine anatomy but rather a risk factor for poor fetal growth, short cervix, and a higher risk pregnancy. KEY POINTS: · Arcuate uterus is associated with increased risk of preterm birth and fetal growth restriction.. · Women with arcuate uteri had higher rates of vaginal progesterone use during pregnancy.. · Arcuate uterus should be treated as a true finding rather than a normal anatomical variant..

Mode of Delivery in Monochorionic Compared With Dichorionic Twin Pregnancies.

OBJECTIVE: To compare mode of delivery between monochorionic and dichorionic twin pregnancies. METHODS: This was a retrospective cohort study of women undergoing delivery of diamniotic twins in a single maternal-fetal medicine practice in New York City between 2005 and 2021. We compared baseline characteristics and delivery outcomes between monochorionic and dichorionic gestations. The primary outcome was mode of delivery. For monochorionic-diamniotic twin pregnancies at or after 34 weeks of gestation, we also compared neonatal outcomes between women who did and did not attempt vaginal delivery. Data were analyzed using the χ2 test, Fisher exact test, and t test when appropriate. RESULTS: A total of 1,121 diamniotic twin pregnancies were identified, of which 202 (18%) were monochorionic and 919 (82%) were dichorionic. Mode of delivery did not differ between monochorionic and dichorionic pregnancies, both in the overall cohort (cesarean delivery rate 61% vs 63%, P=.54) and in the subgroup of women who attempted vaginal delivery (cesarean delivery rate 22% vs 21%, P=.80). For patients with a vaginal delivery of twin A, the mode of delivery for twin B did not differ between the groups. Among the patients with monochorionic pregnancies at or after 34 weeks of gestation, neonatal outcomes did not differ between women who did and did not attempt vaginal delivery. CONCLUSION: Monochorionic-diamniotic pregnancies are not at an increased risk of cesarean delivery when compared with their dichorionic-diamniotic counterparts.

Elective fetal reduction by radiofrequency ablation in monochorionic diamniotic twins decreases adverse outcomes compared to ongoing monochorionic diamniotic twins.

BACKGROUND: Multifetal pregnancy reduction is a technique used to reduce the fetal number to mitigate the risks of adverse outcomes associated with multiple gestations. Monochorionic diamniotic twin pregnancies are subject to unique complications, contributing to adverse pregnancy outcomes. Thus, patients have an option to electively reduce 1 fetus to improve outcomes. OBJECTIVE: This study aimed to compare outcomes of elective reduction of monochorionic diamniotic twins by radiofrequency ablation to planned ongoing monochorionic diamniotic twins. STUDY DESIGN: We performed a retrospective review of 315 monochorionic diamniotic twin gestations that underwent first-trimester ultrasound within 1 institution. Planned electively reduced twins were compared with ongoing monochorionic diamniotic twins. All reductions were performed via radiofrequency ablation of the cord insertion site into the fetal abdomen. The primary outcome was preterm birth at <36 weeks' gestation. Secondary outcomes included gestational age at delivery; preterm birth at less than 37-, 34-, 32-, and 28-weeks' gestation; unintended loss; and adverse perinatal outcomes. RESULTS: Among 315 monochorionic diamniotic pregnancies, 14 (4.4%) underwent elective multifetal pregnancy reduction, and 301 (95.6%) were planned ongoing twins. The mean gestational age of radiofrequency ablation in the elective multifetal pregnancy reduction group was 15.1±0.68 weeks. Patients who underwent elective multifetal pregnancy reduction had significantly higher maternal age (P<.01) and were more likely to be Asian (P<.01). Moreover, they were more likely to have undergone in vitro fertilization (P=.03) and chorionic villus sampling (P<.01). There was a significantly higher rate of term deliveries in the elective radiofrequency ablation group compared with ongoing twins (gestational age, 38 weeks [interquartile range, 36.1-39.1] vs 35.9 weeks [interquartile range, 34.0-36.9]; P<.01). Patients with ongoing pregnancies had a trend of increased rate of preterm birth at <36 weeks' gestation (odds ratio, 3.4; 95% confidence interval, 1.0-12.0; P=.06), a significantly increased risk of preterm birth at <37 weeks' gestation (odds ratio, 8.0; 95% confidence interval, 2.4-26.4; P<.01), and no difference at less than 34-, 32-, or 28- weeks' gestation. All patients who underwent elective radiofrequency ablation had successful pregnancies with no pregnancy losses or terminations. Of ongoing gestations, 36 required procedures, including 16 (5.3%) medically indicated radiofrequency ablation, 14 (4.6%) laser ablation, and 6 (1.9%) amnioreductions. Furthermore, 22 patients (7.3%) with planned ongoing twins had total pregnancy loss at <24 weeks' gestation. Notably, 12 patients (4.0%) had unintended loss of 1 fetus before 24 weeks' gestation in the ongoing pregnancy cohort, and 12 patients (4.0%) had unintended loss of both fetuses before 24 weeks' gestation. Moreover, 5 patients (1.7%) in the ongoing pregnancy group had intrauterine fetal demise at >24 weeks' gestation and 10 patients (3.3%) electively terminated both fetuses. There was no significant difference in loss rates between the 2 groups. CONCLUSION: In this study of monochorionic diamniotic twins, patients who elected to undergo multifetal pregnancy reduction had significantly lower rates of preterm birth at <37 weeks and a lower trend of preterm birth at <36 weeks' gestation without an increased risk of pregnancy loss. Median gestational age at delivery was significantly higher in the elective multifetal pregnancy reduction group (38 weeks) than in the ongoing pregnancy group (35.9 weeks). Further research is needed to clarify if multifetal pregnancy reduction improves long-term outcomes.

The Association between Shirodkar Cerclage and Preterm Premature Rupture of Membranes in Singleton Pregnancies.

OBJECTIVE: The aim of this study was to estimate if preterm premature rupture of membranes in women with cerclage is due to the cerclage itself or rather the underlying risk factors for preterm birth in this population. STUDY DESIGN: This was a retrospective cohort study of singleton pregnancies who underwent Shirodkar cerclage by a single maternal-fetal medicine practice between 2005 and 2019. The control group was an equal number of randomly selected women with a singleton gestation who had a prior preterm birth and were treated with 17-OH-progesterone but no cerclage. Patients with major uterine anomalies or fetal anomalies were excluded. The primary outcome was preterm premature rupture of membranes prior to 34 weeks. Chi-square and logistic regression were used. RESULTS: A total of 350 women with cerclage (154 [44%] history-indicated, 137 [39%] ultrasound-indicated, and 59 [17%] exam-indicated) and 350 controls were included. Preterm premature rupture of membranes prior to 34 weeks did not differ between the groups (8.9% in cerclage vs. 6.0% in controls, p = 0.149, adjusted odds ratio 0.62, 95% confidence interval: 0.24-1.64) nor between the different cerclage indications (9.1% of history-indicated, 7.3% of ultrasound-indicated, and 11.9% of exam-indicated, p = 0.582). This study had 80% power with an α error of 0.05 to detect an increase in preterm premature rupture of membranes prior to 34 weeks from 6.0% in the control group to 12.0% in the cerclage group. CONCLUSION: Cerclage does not increase the risk of preterm premature rupture of membranes prior to 34 weeks compared with other women at increased risk of preterm birth. The observed association between cerclage and preterm premature rupture of membranes is likely due to underlying risk factors and not the cerclage itself. The risk of preterm premature rupture of membranes prior to 34 weeks in women with cerclage is 10% or less and does not appear to differ based on cerclage indication. KEY POINTS: · Cerclage does not increase the risk of PPROM.. · Risk of PPROM with cerclage is approximately 10%.. · Risk does not appear to vary by indication..

Subchorionic Hematomas and Adverse Pregnancy Outcomes among Twin Pregnancies.

OBJECTIVE: This study estimates the association of a first trimester finding of subchorionic hematoma (SCH) with third trimester adverse pregnancy outcomes in women with twin pregnancies. STUDY DESIGN: Retrospective cohort study of twin pregnancies prior to 14 weeks at a single institution from 2005 to 2019, all of whom had a first trimester ultrasound. We excluded monoamniotic twins, fetal anomalies, history of fetal reduction or spontaneous reduction, and twin-to-twin transfusion syndrome. Ultrasound data were reviewed, and we compared pregnancy outcomes after 24 weeks in women with and without a SCH at their initial ultrasound 60/7 to 136/7 weeks. Regression analysis was used to control for any differences in baseline characteristics. RESULTS: A total of 760 women with twin pregnancies met inclusion criteria for the study, 68 (8.9%) of whom had a SCH. Women with SCH were more likely to have vaginal bleeding and had their initial ultrasound at earlier gestational ages. On univariate analysis, SCH was not significantly associated with gestational age at delivery, preterm birth, birthweight of either twin, low birthweight percentiles of either twin, fetal demise, or preeclampsia. SCH was associated with placental abruption on univariate analysis, but not after controlling for vaginal bleeding and gestational age at the time of the initial ultrasound (adjusted odds ratio: 2.00, 95% confidence interval: 0.63-6.42). Among women with SCH, SCH size was not associated with adverse pregnancy outcomes. CONCLUSION: In women with twin pregnancies, the finding of a first trimester SCH is not associated with adverse pregnancy outcomes >24 weeks.

The Association between Placental Histopathology, Fetal Growth Restriction, and Preeclampsia in Twin Pregnancies.

OBJECTIVE: This study aims to estimate the association between abnormal placental histopathology, fetal growth restriction (FGR), and preeclampsia (PEC) in twin pregnancies. STUDY DESIGN: Retrospective cohort study of women with diamniotic twin pregnancies with live births at ≥24 weeks of gestation and available placental pathology. Findings were compared between women with and without FGR, which was defined as a birthweight <10th percentile, using singleton and twin growth curves, and those with and without PEC. The primary study outcome was a composite of abnormal placental histopathology. Chi-square, Fisher's exact, and Student's t-tests were used for analysis. RESULTS: Among 859 patients with diamniotic twins, 806 (93.8%) had placental pathology. A total of 422 (52.4%) women had at least one twin with FGR, using a singleton growth curve. FGR affected 136 (16.9%) pregnancies when a twin growth curve was applied. There was no significant difference in composite outcome between groups, using either growth curve (45.5 vs. 44.8%, p = 0.84; adjusted odds ratio (aOR): 1.06, 95% CI: 0.79-1.40 and 52.2 vs. 43.7%, p = 0.07; aOR: 1.44, 95% CI: 0.90-2.10). A total of 122 of 789 (15.5%) patients developed PEC. There was no significant difference in composite outcome between patients with and without PEC (41.8 vs. 45.4%, p = 0.46; aOR: 0.79, 95% CI: 0.53-1.18). CONCLUSION: In twin pregnancies, FGR and PEC are not associated with abnormal placental histopathology. This suggests that the pathologic placental manifestations of these conditions may differ in twins and include factors other than those commonly described in singletons.