Morbidity In Twin Pregnancies Research Articles

Evaluating the Impact of Maternal Exposure to Ozone on Twin Fetal Growth in China.

Unlike singletons, twins require attention not only to the birth weight of the fetuses but also to discordance (i.e., the differences between weights) because twin growth discordance is a significant factor contributing to perinatal mortality and morbidity in twin pregnancies. However, the impact of maternal air pollution exposure on twin growth discordance has rarely been investigated. We examined the association of long-term ozone exposure during preconception and pregnancy with the birth weight of twins and twin growth discordance among 35,795 twins from the National Free Preconception Health Examination Project between January 2010 and December 2019. Linear mixed-effect models and random-effect logistic regression models were used to examine the associations of ozone exposure with the birth weight-related outcomes (i.e., birth weight of twins and within-pair birth weight difference) and risk of twin growth discordance, respectively, after adjustment for demographic characteristics and lifestyle. We found that an interquartile range (IQR) increase (15 μg/m3) in ozone exposure during the entire pregnancy was associated with a reduction (-28.96g, 95% confidence interval [CI]: -46.37, -11.56) in the total birth weight of twins, and ozone had a more pronounced impact on the birth weight of the smaller fetuses (-18.28 g, 95% CI: -27.22, -9.34) compared to the larger fetuses (-9.88 g, 95% CI: -18.84, -0.92) in twin pregnancies. An IQR increase in ozone exposure during the entire pregnancy was associated with a significant increase (8.41 g, 95% CI: 4.13, 12.69) in the within-pair birth weight difference; the odds ratio (OR) of twin growth discordance related to ozone exposure increased by 9% (OR = 1.09, 95% CI: 1.01, 1.18). However, no consistently significant associations were observed for ozone exposure during prepregnancy. Male-male twin pairs and those who were born prematurely appeared to be more susceptible to ozone exposure than their counterparts. Long-term ozone exposure during pregnancy was associated with twin growth discordance, and our findings provide reference data for future studies.

Pre-pregnancy body mass index and adverse maternal and perinatal outcomes in twins: A population retrospective cohort study.

To examine the association between pre-pregnancy BMI and severe maternal morbidity (SMM), perinatal death and severe neonatal morbidity in twin pregnancies. All twin births at ≥ 20 weeks gestation in British Columbia, Canada, from 2000 to 2017 were included. We estimated rates of SMM, a perinatal composite of death and severe morbidity, and its components per 10,000 pregnancies. Confounder-adjusted rate ratios (aRR) between pre-pregnancy BMI and outcomes were estimated using robust Poisson regression. Overall, 7770 (368 underweight, 1704 overweight, and 1016 obese) women with twin pregnancy were included. The rates of SMM were: 271.1, 320.4, 270.0, and 225.9 in underweight, normal BMI, overweight and obese women, respectively. There was little association between obesity and any of the primary outcomes (e.g., aRR = 1.09, 95% CI = 0.85, 1.38 for composite perinatal outcome). Underweight women had higher rates of the composite perinatal adverse outcome (aRR = 1.79, 95% CI = 1.32-2.43), driven by increased rates of severe respiratory distress syndrome, and neonatal death. There was no evidence of elevated risk of adverse outcomes among twin pregnancies of women who were overweight or obese. Risk was higher in underweight women, who may require specific care when carrying twins.

Evaluation of the Arabin cervical pessary for prevention of preterm birth in women with a twin pregnancy and short cervix (STOPPIT-2): An open-label randomised trial and updated meta-analysis.

BackgroundPreterm-labour-associated preterm birth is a common cause of perinatal mortality and morbidity in twin pregnancy. We aimed to test the hypothesis that the Arabin pessary would reduce preterm-labour-associated preterm birth by 40% or greater in women with a twin pregnancy and a short cervix.Methods and findingsWe conducted an open-label randomised controlled trial in 57 hospital antenatal clinics in the UK and Europe. From 1 April 2015 to 14 February 2019, 2,228 women with a twin pregnancy underwent cervical length screening between 18 weeks 0 days and 20 weeks 6 days of gestation. In total, 503 women with cervical length ≤ 35 mm were randomly assigned to pessary in addition to standard care (n = 250, mean age 32.4 years, mean cervical length 29 mm, with pessary inserted in 230 women [92.0%]) or standard care alone (n = 253, mean age 32.7 years, mean cervical length 30 mm). The pessary was inserted before 21 completed weeks of gestation and removed at between 35 and 36 weeks or before birth if earlier. The primary obstetric outcome, spontaneous onset of labour and birth before 34 weeks 0 days of gestation, was present in 46/250 (18.4%) in the pessary group compared to 52/253 (20.6%) following standard care alone (adjusted odds ratio [aOR] 0.87 [95% CI 0.55–1.38], p = 0.54). The primary neonatal outcome—a composite of any of stillbirth, neonatal death, periventricular leukomalacia, early respiratory morbidity, intraventricular haemorrhage, necrotising enterocolitis, or proven sepsis, from birth to 28 days after the expected date of delivery—was present in 67/500 infants (13.4%) in the pessary group compared to 76/506 (15.0%) following standard care alone (aOR 0.86 [95% CI 0.54–1.36], p = 0.50). The positive and negative likelihood ratios of a short cervix (≤35 mm) to predict preterm birth before 34 weeks were 2.14 and 0.83, respectively. A meta-analysis of data from existing publications (4 studies, 313 women) and from STOPPIT-2 indicated that a cervical pessary does not reduce preterm birth before 34 weeks in women with a short cervix (risk ratio 0.74 [95% CI 0.50–1.11], p = 0.15). No women died in either arm of the study; 4.4% of babies in the Arabin pessary group and 5.5% of babies in the standard treatment group died in utero or in the neonatal period (p = 0.53). Study limitations include lack of power to exclude a smaller than 40% reduction in preterm labour associated preterm birth, and to be conclusive about subgroup analyses.ConclusionsThese results led us to reject our hypothesis that the Arabin pessary would reduce the risk of the primary outcome by 40%. Smaller treatment effects cannot be ruled out.Trial registrationISRCTN Registry ISRCTN 02235181.ClinicalTrials.gov NCT02235181.

Perinatal outcomes of twin pregnancies complicated by late twin-twin transfusion syndrome: A systematic review and meta-analysis.

Untreated twin-to-twin transfusion syndrome (TTTS) is associated with a high risk of perinatal mortality and morbidity. Laser surgery is recommended before 26weeks of gestation. However, the optimal management in case of late TTTS (occurring after 26weeks of gestation) is yet to be established. We conducted a systematic review and meta-analysis to evaluate the outcomes of monochorionic-diamniotic twin pregnancies complicated by late TTTS according to different management options (expectant, laser therapy, amnioreduction, or delivery). The primary outcome was mortality, including single and double intrauterine, neonatal, and perinatal death. Secondary outcomes were composite morbidity, neuromorbidity, respiratory distress syndrome, admission to neonatal intensive care unit, intact survival (ie, free from neurological complications), and preterm birth before <32weeks of gestation. Outcomes were reviewed according to the management and reported for the overall population of twins and disease status (ie, donor and recipient separately). Random-effect meta-analyses of proportions were used to analyze the data. Nine studies including 796 twin pregnancies affected by TTTS were included. No randomized controlled trials were available for inclusion. TTTS occurred at ≥26weeks of gestation in 8.7% (95% CI 6.9%-10.9%; 67/769) of cases reporting TTTS at all gestations. Intrauterine death occurred in 17.7% (95% CI 4.9%-36.2%) of pregnancies managed expectantly, 5.3% (95% CI 0.9%-12.9%) of pregnancies treated with laser, and 0% (95% CI 0%-9%) after amnioreduction. Neonatal death occurred in 42.5% (95% CI 17.5%-69.7%) of pregnancies managed expectantly, in 2.8% (95% CI 0.3%-7.7%) of cases treated with laser, and in 20.2% (95% CI 6%-40%) after amnioreduction. Only one study (10 cases) reported data on immediate delivery after diagnosis with no perinatal deaths. Perinatal death incidence was 55.7% (95% CI 31.4%-78.6%) in twin pregnancies managed expectantly, 5.6% (95% CI 0.5%-15.3%) in those treated with laser, and 20.2% (95% CI 6%-40%) in those after amnioreduction. Intact survival was reported in 44.4%, 96.4%, and 78% of fetuses managed expectantly, with laser or amnioreduction, respectively. Evidence regarding perinatal mortality and morbidity in twin pregnancies complicated by late TTTS according to the different managements was of very low quality. Therefore further high-quality research in this field is needed to elucidate the optimal management of these pregnancies.

Caesarean Section of Multifetal Pregnancy.

Planned caesarean delivery (CD) did not significantly decrease or increase the risk of fetal or neonatal death or serious neonatal morbidity in twin pregnancy between 32 0/7 and 38 6/7 weeks of gestation, with the first twin in the vertex presentation. As prevalence rises for the second twin, emergency CD is necessary for delivery of the second twin after vaginal delivery of the first twin. Waiting after 38 weeks' gestation essentially requires close fetal and maternal surveillance to identify if those pregnancies may benefit to extend a gestational period. It is important to construct a system in which an emergency CD can be performed anytime. The caesarean section does not change in even multifetal pregnancy. Each step after laparotomy has few tips: (1) because the uterus strongly leans to the right, image the uterine rotation. To avoid thick vessels on the uterine lateral wall, perform long U -shaped incision using a scissor. 2) Ensure not to rupture the membrane of the second twin before delivery of the first twin. (3) Check the presentation of the second twin before rupture of that fetus's membrane. The second twin tends to change the presentation. If the upper uterine segment will clamp down and entrap the second twin, a vertical uterine incision is performed without hesitation. Women with multifetal pregnancy are at increased risk of postpartum hemorrhage (PPH). Mainly PPH is caused by uterine atony. Oxytocin should be prepared before starting the CD. All bleeding may not be recognized in the operation field. Do not lose the timing of blood transfusion.

Risk factors and high-risk subgroups of severe acute maternal morbidity in twin pregnancy: A population-based study.

To determine risk factors of severe acute maternal morbidity in women with twin pregnancies and identify subgroups at high risk. In a prospective, population-based study of twin deliveries, the JUMODA cohort, all women with twin pregnancies at or after 22 weeks of gestation were recruited in 176 French hospitals. Severe acute maternal morbidity was a composite criterion. We determined its risk factors by multilevel multivariate Poisson regression modeling and identified high-risk subgroups by classification and regression tree (CART) analysis, in two steps: first considering only characteristics known at the beginning of pregnancy and then adding factors arising during its course. Among the 8,823 women with twin pregnancies, 542 (6.1%, 95% confidence interval (CI) 5.6-6.6) developed severe acute maternal morbidity. Risk factors for severe maternal morbidity identified at the beginning of pregnancy were maternal birth in sub-Saharan Africa (adjusted relative risk (aRR) 1.6, 95% CI 1.1-2.3), preexisting insulin-treated diabetes (aRR 2.2, 95% CI 1.1-4.4), nulliparity (aRR 1.6, 95% CI 1.3-2.0), IVF with autologous oocytes (aRR, 1.3, 95% CI, 1.0-1.6), and oocyte donation (aRR 2.0, 95% CI 1.4-2.8); CART analysis identified nulliparous women with oocyte donation as the subgroup at highest risk (SAMM rate: 14.7%, 95% CI, 10.3-19.1). At the end of pregnancy, additional risk factors identified were placenta praevia (aRR 3.5, 95% CI 2.3-5.3), non-severe preeclampsia (aRR 2.5, 95% CI 1.9-3.2), and macrosomia for either twin (aRR 1.7, 95% CI 1.3-2.1); CART analysis identified women with both oocyte donation and non-severe preeclampsia (SAMM rate: 28.9%, 95% CI, 19.9-37.9) and sub-Saharan nulliparous women with non-severe preeclampsia (SAMM rate: 26.9%, 95% CI, 9.9-43.9) as the two subgroups at highest risk. In woman with twin pregnancy, rates of severe acute maternal morbidity vary between subgroups from 4.6% to 14.7% and from 3.8% to 28.9% at the beginning and at the end of pregnancy respectively, depending on the combined presence of risk factors.

Birthweight discordance and neonatal morbidity in twin pregnancies: A systematic review and meta-analysis.

The aim of this systematic review was to quantify the association between birthweight discordance and neonatal morbidity in twin pregnancies. MEDLINE, Embase and Cinahl databases were searched. Studies reporting the occurrence of morbidity in twins affected compared with those not affected by birthweight discordance were included. The primary outcome was composite neonatal morbidity (including neurological, respiratory, infectious morbidities, abnormal acid-base status and necrotizing enterocolitis). The secondary outcomes were the individual morbidities. Sub-group analysis according to chorionicity, gestational age at birth and fetal weight (smaller vs larger twin) was also performed. Random-effect head-to-head meta-analyses were used to analyze the data. Twenty studies (10851 twin pregnancies) were included. The risk of composite morbidity was significantly higher in the pregnancies with birthweight discordance ≥15% (odds ratio [OR] 1.4, 95% confidence interval [CI] 1.0-1.9), ≥20% (OR 2.2, 95% CI 1.40-3.45), ≥25% (OR 2.5, 95% CI 1.8-3.6), and ≥30% (OR 3.4, 95% CI 2.2-3.2). In dichorionic twins, birthweight discordance ≥15% (OR 2.4, 95% CI 1.65-3.46), ≥20% (OR 2.2, 95% CI 1.3-3.8), ≥25% (OR 2.7, 95% CI 1.4-5.1) and ≥30% (OR 3.6, 95% CI 2.3-5.7) were all significantly associated with composite neonatal morbidity. Analysis of monochorionic twins was hampered by the very small number of included studies, which precluded adequate statistical power. Monochorionic twins with a birthweight discordance ≥20% were at significantly higher risk of composite neonatal morbidity (OR 2.2, 95% CI 1.1-4.9) compared with those presenting with lesser degree of discordance. When stratifying the analysis according to gestational age at birth and fetal size, twins with birthweight discordance ≥15%, 20%, 25% and 30% delivered at ≥34weeks were at higher risk of neonatal morbidity compared with controls, but there was no difference in the risk of morbidity between the larger and the smaller twin in the discordant pair. Birthweight discordance is associated with neonatal morbidity in twin pregnancies. The strength of this association persists for dichorionic twins. It was not possible to extrapolate robust evidence on monochorionic twins due to the low power of the analysis due to the small number of included studies.

148: Mode of conception and risk of severe acute maternal morbidity in twin pregnancies

148: Mode of conception and risk of severe acute maternal morbidity in twin pregnancies

147: Risk factors of severe maternal morbidity in twin pregnancy: national population-based cohort study in France

Compared to women with singletons, women with twin pregnancy are at higher risk of maternal complications. However, among women with twin pregnancy, risk factors for maternal morbidity and subgroups at higher risk of severe maternal outcomes have been poorly characterized. Our objective was to estimate the incidence, causes and risk factors of severe acute maternal morbidity (SAMM) in women with twin pregnancy In a national prospective population-based study of twin deliveries, the JUMODA cohort, all women with twin pregnancies at or after 22 weeks of gestation were recruited in 176 hospitals performing more than 1,500 annual deliveries in France from 02/2014 to 03/2015. SAMM was a composite criterion which combines diagnoses, organ dysfunctions and interventions. The incidence of SAMM was estimated, its timing of occurrence and its causes described. Multilevel multivariate Poisson regression modeling was used to determine risk factors of SAMM and regression tree (CART) analysis to identify high-risk clinical subgroups. Among the 8,823 women with twin pregnancy of the JUMODA cohort, 542 developed SAMM, ie a global incidence of 6.14% (95% CI 5.64-6.64). Most SAMM events occurred during the postpartum period (79.6%). The leading cause was severe obstetric hemorrhage (77.5%; 4.8 for 100 twin maternities). Admission to an Intensive Care Unit occurred in 121 women (1.4 for 100 twin maternities). Women at higher risk of developing severe acute maternal morbidity were those born in Sub-Saharan Africa (aRR 1.44, 95% CI 1.01-2.07), nulliparous (aRR 1.48, 95% CI 1.18-1.85), with pregnancy obtained by vitro fertilization with autologous oocyte (aRR 1.25, 95% CI 1.01-1.55) or with oocyte donation (aRR 1.65, 95% CI 1.17-2.31), with preeclampsia (aRR 2.48, 95% CI 1.94-3.17), placenta praevia (aRR 3.48, 95% CI 2.27-5.32) or macrosomia for either twins (aRR 1.67, 95% CI 1.34-2.07). CART identified women with preeclampsia and oocyte donation as those with the highest risk (28.9%), and multiparous without preeclampsia, placenta praevia and macrosomia as those with the lowest risk (3.8%). About one woman with twin pregnancy out of 17 will develop severe acute maternal morbidity. Identification of subgroups of women at increased risk will allow accurate information of women carrying twins early in and along pregnancy as well as anticipation and potentially prevention of these events in antenatal care and at delivery.View Large Image Figure ViewerDownload Hi-res image Download (PPT)

OC07.01: Perinatal mortality and morbidity in twin pregnancies with selective fetal growth restriction according to their management: a meta‐analysis

OC07.01: Perinatal mortality and morbidity in twin pregnancies with selective fetal growth restriction according to their management: a meta‐analysis

Association Between Perinatal Outcomes and Mode of Conception in Twin Pregnancies [8B

INTRODUCTION: Artificial reproductive technology (ART) is associated with increased risks of adverse perinatal outcomes in singleton gestations; however, the association in twin gestations is less clear. Minimal data exists on the impact of oral and injectable fertility medications on maternal and perinatal outcomes in twins. Our objective was to examine the impact of conception method on perinatal outcomes. METHODS: We performed a retrospective cohort of all twin pregnancies delivered in a single-tertiary care-center with ultrasound evaluation between 1/1/2013 and 4/1/2016. Women with unknown conception method, missing maternal or neonatal data, and monochorionic-monoamniotic twins were excluded. The primary outcome was maternal and neonatal morbidity in twin pregnancies conceived among three groups. RESULTS: Of 424 twin pregnancies during the study period, 417 met inclusion criteria. 199 conceived spontaneously (G1), 86 conceived through oral/injectable medications (G2), and 132 conceived through in-vitro fertilization (IVF) (G3). Compared to G1, G2 and G3 were more likely nulliparous, privately insured, diagnosed with preeclampsia (G2: P=.03; G3: P&lt;.01), experienced greater rates of postpartum hemorrhage (G2: P=.02; G3: P&lt;.01) and less likely to conceive monochorionic-diamniotic twins. No difference was noted in composite maternal or neonatal morbidity between groups. CONCLUSION: Twin gestations conceived via IVF or oral/injectable medications are similarly associated with an increased risk of preeclampsia and postpartum hemorrhage compared to spontaneous conception. Women who conceive by infertility treatment, regardless of the type, should be counseled regarding this increased maternal risk.

Long-term outcomes of twins based on gestational age at delivery

Objective: Prematurity is associated with adverse outcomes. However, there are less data regarding long-term outcomes of twins based on gestational age at delivery. Our objective was to identify the association between gestational age at delivery and long-term outcomes in twins.Study design: All patients with a twin pregnancy ≥24 weeks delivered by a single Maternal Fetal Medicine practice from 2005 to 2014 were surveyed regarding pediatric outcomes at or after 2 years of life. We excluded twins with aneuploidy or major fetal anomalies. The survey was mail-based, with phone follow-up for nonresponses or for clarification. Using logistic regression analysis, we compared long-term outcomes between twins born in four gestational age groups: 24 to 27–6/7 weeks, 28 to 31–6/7 weeks, 32 to 35–6/7 weeks, and 36 weeks or later.Results: Six hundred fifty-three twin deliveries met inclusion criteria and 425 (65.1%) mothers responded. Mean age at the time of survey completion was 6.0 ± 2.4 years. Earlier gestational age was significantly associated with neonatal death (14, 2, 0, and 0% in the four groups, respectively, p < .001). Prematurity was associated with a composite of major adverse outcomes (death; cerebral palsy; necrotizing enterocolitis; chronic renal, heart, or lung disease) (14, 7, 4, and 2% in the four groups, p = .036), as well as minor adverse outcomes (learning disability; need for speech, occupational, or physical therapy) (83, 69, 54, and 38%, p < .001).Conclusions: Long-term morbidity in twin pregnancies is inversely related to gestational age at delivery. However, for twins born after 28 weeks, neonatal death and severe long-term morbidity are rare.

Naproxen Sodium for Pain Control With Intrauterine Device Insertion: A Randomized Controlled Trial.

Naproxen Sodium for Pain Control With Intrauterine Device Insertion: A Randomized Controlled Trial.

Association Between Planned Cesarean Delivery and Neonatal Mortality and Morbidity in Twin Pregnancies.

To evaluate the association between the planned mode of delivery and neonatal mortality and morbidity in an unselected population of women with twin pregnancies. The JUmeaux MODe d'Accouchement (JUMODA) study was a national prospective population-based cohort study. All women with twin pregnancies and their neonates born at or after 32 weeks of gestation with a cephalic first twin were recruited in 176 maternity units in France from February 2014 to March 2015. The primary outcome was a composite of intrapartum mortality and neonatal mortality and morbidity. Comparisons were performed according to the planned mode of delivery, planned cesarean or planned vaginal delivery. The primary analysis to control for potential indication bias used propensity score matching. Subgroup analyses were conducted, one according to gestational age at delivery and one after exclusion of high-risk pregnancies. Among 5,915 women enrolled in the study, 1,454 (24.6%) had planned cesarean and 4,461 (75.4%) planned vaginal deliveries, of whom 3,583 (80.3%) delivered both twins vaginally. In the overall population, composite neonatal mortality and morbidity was increased in the planned cesarean compared with the planned vaginal delivery group (5.2% compared with 2.2%; odds ratio [OR] 2.38, 95% confidence interval [CI] 1.86-3.05). After matching, neonates born after planned cesarean compared with planned vaginal delivery had higher composite neonatal mortality and morbidity rates (5.3% compared with 3.0%; OR 1.85, 95% confidence interval 1.29-2.67). Differences in composite mortality and morbidity rates applied to neonates born before but not after 37 weeks of gestation. Multivariate and subgroup analyses after exclusion of high-risk pregnancies found similar trends. Planned vaginal delivery for twin pregnancies with a cephalic first twin at or after 32 weeks of gestation was associated with low composite neonatal mortality and morbidity. Moreover, planned cesarean compared with planned vaginal delivery before 37 weeks of gestation might be associated with increased composite neonatal mortality and morbidity.

Association of Intended Route of Delivery and Maternal Morbidity in Twin Pregnancy.

Association of Intended Route of Delivery and Maternal Morbidity in Twin Pregnancy.

Association of Intended Route of Delivery and Maternal Morbidity in Twin Pregnancy.

To evaluate maternal morbidity in twin pregnancies according to intended mode of delivery. We assembled a 7-year retrospective cohort (2007-2014) of women delivering viable, vertex-presenting twins at or beyond 32 weeks of gestation without contraindication to labor or uterine scar. We classified women as undergoing a trial of labor to attempt vaginal birth or choosing an elective cesarean delivery. Our primary outcome was a measure of composite maternal morbidity including death, postpartum hemorrhage, infection, major procedure, readmission for infection or reoperation, need for dilation and evacuation for hemorrhage or infection, venous thromboembolism, small bowel obstruction or ileus, or intensive care unit admission. Postpartum hemorrhage was defined as estimated blood loss greater than or equal to 1,500 mL or need for transfusion. The rate of lacerations in each group was also determined. Using logistic regression to control for confounders, we examined the odds of maternal morbidity according to intended mode of delivery. Of 2,272 twin pregnancies at or beyond 32 weeks of gestation, 1,140 (50%) met inclusion criteria with 571 (50%) electing cesarean delivery and 569 (50%) undergoing a trial of labor to attempt vaginal birth. Vaginal delivery of both twins was achieved in 74% (n=418) of women choosing a trial of labor. The rate of maternal morbidity was 12.3% in the trial of labor group compared with 9.1% in the elective cesarean delivery group (P=.08, adjusted odds ratio [OR] 1.6, 95% confidence interval [CI] 1.1-2.4). Postpartum hemorrhage was more common among women who attempted vaginal delivery (n=52) compared with those electing cesarean delivery (n=28) with rates of 9.1% compared with 4.9%, respectively (P<.01, adjusted OR 2.2, 95% CI 1.4-3.6) and was responsible for the difference in the composite morbidity rate between groups. When adjustment is made for potential confounders, women undergoing a trial of labor with twins experience a higher odds of maternal morbidity than those electing cesarean delivery, primarily as a result of hemorrhage. In pragmatic terms, the tradeoff for a 74% chance of vaginal delivery is a 4% absolute increase in the rate of serious postpartum hemorrhage.

Is Cesarean Delivery Preferable in Twin Pregnancies at >=36 Weeks Gestation?

BackgroundThe optimal mode of delivery in twin pregnancies remains controversial. A recent randomized trial did not find any benefit of planned cesarean vs. vaginal delivery at 32–38 weeks gestation, but the trial was not powered to detect a moderate effect. We aimed to evaluate the impact of cesarean delivery on perinatal mortality and severe neonatal morbidity in twin pregnancies at ≥32 weeks through a large database exploration approach with the power to detect moderate risk differences.MethodsIn a retrospective birth cohort study using the U.S. matched multiple births, 1995–2000 (the available largest multiple birth dataset), we compared perinatal outcomes in twins (n = 181,810 pregnancies) delivered at 32–41 weeks gestation without congenital anomalies. The primary outcome was a composite of perinatal death and severe neonatal morbidity. Cox regression was used to estimate the adjusted hazard ratio (aHR) controlling for the propensity to cesarean delivery, fetal characteristics (sex, birth weight, birth weight discordance, same-sex twin or not) and twin-cluster level dependence. Prospective risks were calculated using the fetuses-at-risk denominators.ResultsThe overall rates of the primary outcome were slightly lower in intended cesarean (6.20%) vs. vaginal (6.45%) deliveries. The aHRs of the primary outcome were in favor of vaginal delivery at 32 (aHR = 1.06, p = 0.03) or 33 (aHR = 1.22, p<0.001) weeks, neutral at 34–35 weeks, but in favor of cesarean delivery at 36 (aHR = 0.94, p = 0.004), 37, 38 and 39+ weeks (aHR: 0.72 to 0.78, all p<0.001). The lower risk of the primary outcome for cesarean vs. vaginal deliveries at 36+ weeks of gestation remained when the analyses were restricted to different-sex (dichorionic) twins (aHR = 0.84, 95% CI 0.80–0.88).ConclusionCesarean delivery may be beneficial for perinatal outcomes overall in twin pregnancies at ≥36 weeks gestation.

P15.06: Discordance in fetal biometry and Doppler are independent predictors of the risk of neonatal morbidity in twin pregnancies

P15.06: Discordance in fetal biometry and Doppler are independent predictors of the risk of neonatal morbidity in twin pregnancies

Mode of delivery of twin gestation with very low birthweight: is vaginal delivery safe?

The purpose of this study was to determine whether planned vaginal delivery is associated with increased risk of perinatal death and morbidity in twin pregnancies that are complicated by a very low birthweight of the second twin. We conducted a retrospective cohort study of twin pregnancies in which the second twin's birthweight was ≤1500 g. One hundred ninety-three twin gestations met the study criteria; patients were classified into 2 groups according to the planned mode of delivery: (1) cesarean delivery (n = 142) and (2) vaginal delivery (n = 51). In the vaginal delivery group, 21 pairs were in cephalic-cephalic presentation at the time of delivery; 28 pairs were cephalic-noncephalic, and 2 pairs were noncephalic-noncephalic. Composite adverse neonatal outcome was defined as the presence of neonatal death, respiratory distress syndrome, sepsis, necrotizing enterocolitis, or intraventricular hemorrhage grade 3-4. Trial of vaginal delivery was successful for both twins in 90.5% of cephalic-cephalic twins and 96.4% in cephalic-noncephalic twins. The rate of intraventricular hemorrhage was significantly higher in the vaginal delivery group (29.4% vs 8.5%, respectively; P = .013; adjusted odds ratio [OR], 3.65; 95% confidence interval [CI], 1.32-10.1). The increased risk of intraventricular hemorrhage in the vaginal delivery groups was evident in both twin A (17.6% vs 7.0%; P = .029) and twin B (15.7% vs 4.9%; P = .014); however, these differences were not significant after adjustment for possible confounders (twin A: adjusted OR, 1.79; 95% CI, 0.58-5.55; twin B: adjusted OR, 2.13; 95% CI, 0.63-7.25). In addition, subgroup analysis revealed that both cephalic-cephalic and cephalic-noncephalic twins who were delivered vaginally had increased risk for intraventricular hemorrhage. There were no significant differences between the cesarean and vaginal delivery groups in the rates of Apgar score <7 at 5 minutes, arterial cord pH <7.1, composite adverse neonatal outcome, and neonatal mortality rate. However, the rate of respiratory distress syndrome was significantly lower in the vaginal delivery group (66.7% vs 69%; P = .042; OR, 0.34; 95% CI, 0.12-0.96). Vaginal delivery of very low birthweight twins is associated with an increased risk of intraventricular hemorrhage, regardless of presentation. Because of the small sample size and the retrospective cohort design, large prospective randomized studies are needed.

Perinatal Mortality and Morbidity in Twin Pregnancies

Aim To investigate perinatal mortality and morbidity rates of twin pregnancies and to determine the underlying factors responsible for the increase in these rates.