Trends in the delivery route of twin pregnancies in the United States, 2006–2013

Surgical-site infection in multifetal cesarean delivery

PURPOSE

The relationship between multifetal cesarean delivery and surgical-site infection (SSI) is unclear. If SSI is more common in multifetal cesareans, adjustment of practices such as antibiotic dosing could be warranted. The purpose of this study was to determine whether patients undergoing multifetal cesarean delivery are more likely to experience SSI than those undergoing singleton cesarean delivery.

METHODS

This was a retrospective cohort study including all cesarean deliveries at a tertiary hospital from 10/1/2009 to 12/28/2018. The primary outcome was rate of SSI in women after multifetal cesarean delivery as compared to those who underwent singleton cesarean delivery. Univariable analysis and multivariable logistic regression were used to assess independent clinical factors associated with SSI in multifetal cesarean deliveries.

RESULTS

34,340 women underwent cesarean delivery during this period. 33,211 were singletons (96.7%), and 1,129 were multifetal (3.3%). There was no difference in the rate of SSI in multifetal gestations (15/1,129, 1.3%) as compared to singletons (493/33,211, 1.5%) (p = 0.670, OR 0.89 [95% CI 0.53, 1.50], aOR 1.06 [95% CI 0.61, 1.84]). Limiting analysis to multifetal deliveries, prolonged rupture of membranes (p < 0.004, OR 5.43 [95% CI 1.49, 19.88]), labor augmentation (p < 0.001, OR 15.84 [1.74, 144.53]), and chorioamnionitis (p < 0.001, OR 15.43 [95% CI 3.11, 76.62]) were more common in women with SSI.

DISCUSSION

SSI is not increased in multifetal cesarean delivery as compared to singleton cesarean delivery. In multifetal cesareans, chorioamnionitis, prolonged rupture of membranes, and labor augmentation were associated with increased odds of SSI.

Methods for the induction of labor: efficacy and safety

This review assessed the efficacy and safety of pharmacologic agents (prostaglandins, oxytocin, mifepristone, hyaluronidase, and nitric oxide donors) and mechanical methods (single- and double-balloon catheters, laminaria, membrane stripping, and amniotomy) and those generally considered under the rubric of complementary medicine (castor oil, nipple stimulation, sexual intercourse, herbal medicine, and acupuncture). A substantial body of published reports, including 2 large network meta-analyses, support the safety and efficacy of misoprostol (PGE1) when used for cervical ripening and labor induction. Misoprostol administered vaginally at doses of 50 μg has the highest probability of achieving vaginal delivery within 24 hours. Regardless of dosing, route, and schedule of administration, when used for cervical ripening and labor induction, prostaglandin E2 seems to have similar efficacy in decreasing cesarean delivery rates. Globally, although oxytocin represents the most widely used pharmacologic agent for labor induction, its effectiveness is highly dependent on parity and cervical status. Oxytocin is more effective than expectant management in inducing labor, and the efficacy of oxytocin is enhanced when combined with amniotomy. However, prostaglandins administered vaginally or intracervically are more effective in inducing labor than oxytocin. A single 200-mg oral tablet of mifepristone seems to represent the lowest effective dose for cervical ripening. The bulk of the literature assessing relaxin suggests this agent has limited benefit when used for this indication. Although intracervical injection of hyaluronidase may cause cervical ripening, the need for intracervical administration has limited the use of this agent. Concerning the vaginal administration of nitric oxide donors, including isosorbide mononitrate, isosorbide, nitroglycerin, and sodium nitroprusside, the higher incidence of side effects with these agents has limited their use. A synthetic hygroscopic cervical dilator has been found to be effective for preinduction cervical ripening. Although a pharmacologic agent may be administered after the use of the synthetic hygroscopic dilator, in an attempt to reduce the interval to vaginal delivery, concomitant use of mechanical and pharmacologic methods is being explored. Combining the use of a single-balloon catheter with dinoprostone, misoprostol, or oxytocin enhances the efficacy of these pharmacologic agents in cervical ripening and labor induction. The efficacy of single- and double-balloon catheters in cervical ripening and labor induction seems similar. To date, the combination of misoprostol with an intracervical catheter seems to be the best approach when balancing delivery times with safety. Although complementary methods are occasionally used by patients, given the lack of data documenting their efficacy and safety, these methods are rarely used in hospital settings.

Disparities in Trial of Labor among Women with Twin Gestations in the United States

OBJECTIVE

The aim of the study is to examine clinical and demographic factors associated with trial of labor (TOL) among women with twin gestations eligible for a vaginal delivery.

STUDY DESIGN

This was a population-based cohort study of women giving birth to twin gestations in the United States (2012-2014). Inclusion criteria for the analysis included live births greater than 23 weeks' gestation and a cephalic presenting twin. Women with prior cesarean delivery were excluded. Women were categorized by whether they underwent a TOL. Clinical and demographic characteristics associated with TOL status were evaluated using multivariable logistic regression analyses. Secondary analyses with stratification by parity and by second twin presentation were performed.

RESULTS

Of 90,000 women eligible for inclusion, a minority (39.3%) underwent TOL. Women who had a greater gestational age at delivery were more likely to have a TOL. In contrast, several demographic factors were associated with decreased likelihood of TOL, including maternal age >35 years and identifying as Hispanic or Asian compared with non-Hispanic White. No differences in odds of TOL were observed for women who were identified as non-Hispanic Black versus non-Hispanic White, nor were other demographic factors such as marital status, insurance status, or educational attainment associated with undergoing TOL. Clinical factors associated with decreased odds of TOL included nulliparity, obesity, and hypertensive disorders of pregnancy. Results did not substantively change when stratified by parity or second twin presentation, nor did findings differ in the subgroup who delivered at 32 weeks of gestation or greater.

CONCLUSION

In this large population of women with twins who were eligible for a TOL, a minority of individuals attempted a vaginal delivery. Demographic and clinical factors such as older maternal age, Asian or Hispanic racial or ethnic identification, nulliparity, and obesity are associated with decreased odds of undergoing TOL.

KEY POINTS

· Understanding disparities in trial of labor among patients with twins is key to promoting equity.. · Older maternal age and identifying as Hispanic or Asian were associated with lower odds of TOL.. · Nulliparity, obesity, and hypertension were associated with decreased odds of TOL..

Experience in different modes of delivery in twin pregnancy

Background/purpose

Vaginal delivery, compared with Cesarean delivery, remains a less chosen mode of delivery for twin pregnancy. We studied the maternal and perinatal outcomes of twin pregnancy with different modes of delivery.

Methods

A retrospective study with data collected from a regional hospital, including vital twin pregnancies delivered at gestational age of 32 weeks and above. Medical charts were reviewed for prenatal conditions and postpartum outcomes.

Results

Ninety-eight pairs of twins were included and 44.9% were delivered via vaginal delivery. Women in the vaginal delivery group were significantly younger (32.5 ±4.3 years versus 34.8 ±4.6 years, p < 0.01), multiparous (34.1% versus 18.5%) and with more twins in vertex-vertex presentation (70.5% versus 33.3%) compared with women in the Cesarean delivery group. There were no differences between maternal postpartum complications and neonatal outcomes in both groups. The outcomes showed longer inter-twin delivery time interval (5.7 ± 5.6 versus 1.5 ± 0.9 min, p < 0.01), less estimated blood loss (198.7 ± 144.1 versus 763.2 ± 332.3 mL, p < 0.01), and shorter maternal hospital stay (3.0 ± 0.5 versus 5.7 ± 0.5 days, p< 0.01) in the vaginal delivery group. Twenty newborns had Apgar score below seven at birth. Logistic regression analysis revealed that low Apgar score was independently related to younger maternal age, maternal obstetric diseases and fetal non-vertex presentation. Gestational weeks and mode of delivery were not related to low Apgar score.

Conclusion

With careful case selection, vaginal delivery could be safely performed in twin pregnancies with less estimated blood loss and better recovery than Cesarean delivery.

Norepinephrine versus phenylephrine infusion for preventing postspinal hypotension during cesarean section for twin pregnancy: a double-blinded randomized controlled clinical trial

Background

Compared with singleton pregnancy, twin gestation is featured by a greater increase in cardiac output. Therefore, norepinephrine might be more suitable than phenylephrine for maintaining blood pressure during cesarean section for twins, as phenylephrine causes reflex bradycardia and a resultant decrease in cardiac output. This study was to determine whether norepinephrine was superior to phenylephrine in maintaining maternal hemodynamics during cesarean section for twins.

Methods

Informed consent was obtained from all the patients before enrollment. In this double-blinded, randomized clinical trial, 100 parturients with twin gestation undergoing cesarean section with spinal anesthesia were randomized to receive prophylactic norepinephrine (3.2 μg/min) or phenylephrine infusion (40 μg/min). The primary outcome was the change of heart rate and blood pressure during the study period. The secondary outcomes were to compare maternal complications, neonatal outcomes, Apgar scores and umbilical blood acid-base status between the two vasopressors.

Results

There was no significant difference observed for the change of heart rate between two vasopressors. The mean standardized area under the curve of heart rate was 78 ± 12 with norepinephrine vs. 74 ± 11 beats/min with phenylephrine (mean difference 4.4, 95%CI − 0.1 to 9.0; P = .0567). The mean standardized area under the curve of systolic blood pressure (SBP) was significantly lower in parturients with norepinephrine, as the mean of differences in standardized AUC of SBP was 6 mmHg, with a 95% CI from 2 to 9 mmHg (P = .0013). However, requirements of physician interventions for correcting maternal hemodynamical abnormalities (temporary cessation of vasopressor infusion for reactive hypertension, rescuing vasopressor bolus for hypotension and atropine for heart rate less < 50 beats/min) and neonatal outcomes were also not significantly different between two vasopressors.

Conclusion

Infusion of norepinephrine was not associated with less overall decrease in heart rate during cesarean section for twins, compared with phenylephrine.

Trial registration

Chinese Clinical Trial Registry (ChiCTR1900021281).

The Charité external cephalic version for leading twin breech without regional anesthesia and tocolysis. A prospective study on feasibility, sonographic assessment and outcomes

OBJECTIVES

To assess the feasibility of external cephalic version (ECV) for the leading twin (twin A) in breech presentation in dichorionic and diamniotic twin pregnancies without the use of regional anesthetics and tocolysis and to characterize the sonographic parameters, maternal and neonatal outcomes.

STUDY DESIGN

Prospective study performed in the Charité University Hospital outpatient obstetric department in Berlin, Germany. A total of 23 women from the 35th completed week of pregnancy with confirmed dichorionic-diamniotic twin pregnancy were recruited. ECVs were performed by the lead consultant for the breech and ECV clinic. Ethical approval provided by the Charité Ethics Commission (EA2/241/18). Demographic data were recorded. Fetal sonographic parameters were assessed. The success rate of ECV, duration of the ECV, gestational age at delivery, mode of delivery for both fetuses, maternal and neonatal outcomes were analyzed.

RESULTS

Our main finding showed that ECV for twin A breech in dichorionic-diamniotic twins is successful in 56% (10/18) of cases without the need for regional anesthesia and without tocolysis. There is a significant increase in the spontaneous vaginal delivery rate for both twins of 95% (19/20) vs 12.5% (2/16) (p < 0.001). There is also a significant reduction in blood loss at delivery of 300 ml vs 500 ml (p = 0.034) in successful cases.

CONCLUSIONS

We show that ECV for twin A in breech is feasible and in 56% (10/18) successful without regional anesthesia and tocolysis. The option of ECV for twin A breech should be offered to women.

Normal labor curve in twin gestation

BACKGROUND

Failure to progress is one of the leading indications for cesarean delivery in trials of labor in twin gestations. However, assessment of labor progression in twin labors is managed according to singleton labor curves.

OBJECTIVE

This study aimed to establish a partogram for twin deliveries that reflects normal and abnormal labor progression and customized labor curves for different subgroups of twin labors.

STUDY DESIGN

This was a multicenter, retrospective cohort analysis of twin deliveries that were recorded in 3 tertiary medical centers between 2003 and 2017. Eligible parturients were those with twin gestations at ≥34 weeks' gestation with cephalic presentation of the presenting twin and ≥2 cervical examinations during labor. Exclusion criteria were elective cesarean delivery without a trial of labor, major fetal anomalies, and fetal demise. The study group comprised twin gestations, whereas singleton gestations comprised the control group. Statistical analysis was performed using Python 3.7.3 and SPSS, version 27. Categorical variables were analyzed using chi-square tests. Student t test and Mann-Whitney U test were applied to analyze the differences in continuous variables, as appropriate.

RESULTS

A total of 1375 twin deliveries and 142,659 singleton deliveries met the inclusion criteria. Duration of the active phase of labor was significantly longer in twin labors than in singleton labors in both nulliparous and multiparous parturients; the 95th percentile duration was 2 hours longer in nulliparous twin labors and >3.5 hours longer in multiparous twin labors than in singleton labors. The cervical dilation progression rate was significantly slower in twin deliveries than in singleton deliveries with a mean rate in twin deliveries of 1.89 cm/h (95th percentile, 0.51 cm/h) and a mean rate of 2.48 cm/h (95th percentile, 0.73 cm/h) in singleton deliveries (P<.001). In addition, epidural use further slowed labor progression in twin deliveries. The second stage of labor was also markedly longer in twin deliveries, both in nulliparous and multiparous women (95th percentile, 3.04 vs 2.83 hours, P=.002).

CONCLUSION

Twin labors are characterized by a slower progression of the active phase and second stage of labor compared with singleton labors in nulliparous and multiparous parturients. Epidural analgesia further slows labor progression in twin labors. Implementation of these findings in clinical management might lower cesarean delivery rates among cases with protracted labor in twin gestations.

Impact of mode of delivery on perinatal outcome in moderately and late preterm twin birth

OBJECTIVE

To examine the impact of the mode of delivery on neonatal and maternal outcomes in moderately and late preterm twin birth.

METHODS

This single-center cohort study included 275 live diamniotic moderately and late preterm twin deliveries at 32⁺⁰ -36⁺⁶  weeks of gestation. These twin deliveries were divided into two groups according to the planned mode of delivery: trial of labor (TOL) (N=199, 72.4%) and planned cesarean section (CS) (N=76, 27.6%). The primary outcome was neonatal morbidity. Maternal outcome and the effects of gestational age and chorionicity on neonatal outcome were also studied.

RESULTS

Of the women in the TOL group, 170 (85.4%) delivered vaginally. Both for the first and second twin, and for dichorionic or monochorionic deliveries, there were no differences between the TOL and CS groups in composite neonatal morbidity or in other neonatal outcomes. No significant differences were found between the TOL and CS groups when the moderately and late preterm gestational age cohorts were studied separately. Mothers in the planned CS group more often had puerperal infection and surgical complications in comparison with mothers in the TOL group.

CONCLUSION

Among 275 moderately and late preterm twin deliveries, planned mode of delivery did not affect neonatal outcome.

Induction of Labor versus Cesarean Delivery in Twin Pregnancies

OBJECTIVE

This study was aimed to compare maternal and neonatal outcomes between women with twin pregnancies who underwent induction of labor with those women who had planned Cesarean delivery (CD).

STUDY DESIGN

This is a retrospective cohort study of women with twin pregnancies ≥ 24 weeks with an indication for delivery but not in labor. Two groups were examined, women who underwent induction and women who underwent planned CD. Maternal and neonatal outcomes were compared between groups both for deliveries at gestational age ≥ 37 weeks and < 37 weeks.

RESULTS

A total of 453 patients were included. Overall, 212 (46.8%) women underwent induction and 241 (53.2%) underwent planned CD. Women who underwent induction of labor had a high rate of VD, both in the term and preterm groups (69.8 and 73.6%, respectively). Women who underwent induction of labor had reduced maternal length of stay, neonatal length of stay, and blood loss, without any increase in adverse outcomes. Neonatal ventilation of either twin delivered < 37 weeks was higher in the CD compared with induction group (27.5 vs. 9.4%, p < 0.01), but this was not significant on adjusted odds ratio analysis (aOR = 0.71, 95% CI: 0.19-2.66).

CONCLUSION

Labor induction in twin gestations have improved maternal outcomes and similar neonatal outcomes compared with planned CD.

Anal Sphincter Injury Associated with Vaginal Twin Delivery

OBJECTIVE

Obstetric anal sphincter injury remains the most common cause of fecal incontinence in women, and research in twin pregnancies is sparse. This study aimed to examine risk factors for sphincter injury in twin deliveries over a 10-year period.

STUDY DESIGN

This was a retrospective study of twin vaginal deliveries in a tertiary-level hospital over 10 years. We examined the demographics of women who had a vaginal delivery of at least one twin. Logistic regression analysis was used to examine risk factors.

RESULTS

There were 1,783 (2.1%) twin pregnancies, of which 556 (31%) had a vaginal delivery of at least one twin. Sphincter injury occurred in 1.1% (6/556) women with twins compared with 2.9% (1720/59,944) singleton vaginal deliveries. Women with sphincter injury had more instrumental deliveries (83.3 vs. 27.6%; p = 0.008). On univariate analysis, only instrumental delivery was a significant risk factor (odds ratio: 2.93; p = 0.019).

CONCLUSION

Sphincter injury occurs at a lower rate in vaginal twin pregnancies than in singletons. No twin-specific risk factors were identified. Discussion of the risk of sphincter injury should form part of patient counseling with regard to the mode of delivery.

Risk factors of unsuccessful vaginal twin delivery

INTRODUCTION

Twin trial of labor presents a challenge to obstetricians, as it is associated with a greater number of adverse birth outcomes compared with singleton deliveries. The risk of poor outcome has shown to be highest with unsuccessful vaginal twin delivery. The purpose of this study was to identify the clinical risk factors associated with intrapartum cesarean section in late preterm and term twin births.

MATERIAL AND METHODS

All live diamniotic twin deliveries of at least 35⁺⁰ weeks of gestation with planned vaginal delivery were included in this retrospective single-center cohort study. Maternal and newborn characteristics were compared between a vaginal delivery group and an intrapartum cesarean section group. Logistic regression analysis was carried out to determine independent risk factors of intrapartum cesarean section. Further, maternal and neonatal outcomes were compared between groups of vaginal delivery and cesarean section for both twins and also between groups of vaginal delivery and cesarean section for the second twin only (combined delivery). The impact of presentation of the second twin on the mode of twin delivery and on neonatal outcome was also examined.

RESULTS

Among 821 twin pregnancies, 581 mothers (70.8%) attempted trial of labor and were eligible for the study. With a cephalic-presenting first twin, the trial of labor rate was 89.3% and vaginal delivery was successful in 82.8%. Nulliparity (odds ratio [OR] 3.2, 95% confidence interval [CI] 2.0-5.1) and non-cephalic presentation of the second twin (OR 3.0, 95% CI 1.9-4.8) were found to be independent risk factors of cesarean section. However, 76.1% of mothers with non-cephalic second twins achieved vaginal delivery and perinatal outcomes were comparable with cases of cephalic-presenting second twins. When comparing delivery modes, maternal outcomes were more favorable with vaginal delivery, whereas combined delivery increased the second twin's risk of adverse neonatal outcome.

CONCLUSIONS

This study, with high rates of trial of labor and successful vaginal twin delivery, found nulliparity and non-cephalic presentation of the second twin to be risk factors of intrapartum cesarean section in twin pregnancies.

Maternal morbidity of induction of labor compared to planned cesarean delivery in twin gestations

Objective: To compare maternal morbidity associated with induction of labor (IOL) with planned cesarean delivery (CD) in twin gestations.Methods: This was a retrospective cohort study of vertex-presenting twin pregnancies ≥24-week gestation delivering at our institution from 2016 to 2017. We compared patients undergoing IOL with patients undergoing planned CD. Demographic and pregnancy outcome data were abstracted from the medical record. Our primary outcome was composite maternal morbidity including severe postpartum hemorrhage (PPH) (EBL >1500 cc), hysterectomy, transfusion, ICU admission, use of ≥2 uterotonic medications or maternal death. These morbidities were also assessed independently. Secondary analyses of maternal morbidity among unplanned CD versus planned CD and successful IOL versus planned CD was also performed. Chi-square, Mann-Whitney U and multivariate logistic regression were used in statistical analysis.Results: Of 211 twin gestations included, 70.6% were nulliparous, the median age was 35.5 years [32-38], and the median gestational age at delivery was 37 weeks [35-38]. One hundred and five underwent IOL and 106 had a planned CD. Composite morbidity was higher in the IOL group versus planned CD group (30.5 versus 11.3%, p = .001). In the IOL group, 64 (61.0%) achieved a vaginal delivery. Patients in the planned CD group were more likely to be >35 years of age (62.3 versus 48.6%, p = .045), nulliparous (80.2 versus 61.0%, p = .002) and deliver preterm (53.8 versus 38.1%, p = .022). Patients with a planned CD had a significantly lower risk of composite morbidity compared to those who had CD after failed IOL (11.3 versus 48.8%, p ≤ .001) and there was no significant difference in composite morbidity in the successful IOL compared to the planned CD group (18.8 versus 11.3%, p = .18). There were four peri-partum hysterectomies, all within the IOL group.Conclusion: Labor induction in twins was associated with increased maternal morbidity compared to planned CD. The increase in adverse maternal outcomes was due to those who underwent an IOL and ultimately required CD.

Comparing pregnancy outcomes and loss rates in elective twin pregnancy reduction with ongoing twin gestations in a large contemporary cohort

BACKGROUND

As compared with singleton gestations, twin pregnancies are associated with a significantly higher risk of preterm birth and maternal complications as well as fetal and neonatal morbidity and mortality. Multifetal pregnancy reduction is a technique developed in the 1980s to reduce the fetal number in higher-order multiple pregnancies to reduce the risk of adverse pregnancy outcomes, most importantly preterm birth.

OBJECTIVE

The objective of the study was to compare pregnancy outcomes and loss rates in elective twin pregnancy reduction to ongoing twin gestations in a large contemporary cohort.

STUDY DESIGN

This was a retrospective review of dichorionic diamniotic twin gestations that underwent first-trimester ultrasound at our institution from January 2008 to September 2016. Planned elective 2-to-1 multifetal pregnancy reductions at less than 15 weeks' gestation were compared with ongoing dichorionic diamniotic twin gestations. Data were collected via chart review. Demographics between 2-to-1 reduced singletons and ongoing twins were assessed using a Student t test or a Wilcoxon rank-sum test, as appropriate, for continuous variables and χ² or Fisher exact tests, as appropriate, for categorical variables. Univariable and multivariable logistic regressions were used to compare pregnancy outcomes between ongoing twins and reduced singletons adjusting for maternal age, body mass index, race, in vitro fertilization, use of chorionic villus sampling, prior term birth, and prior preterm birth.

RESULTS

Of 1070 dichorionic diamniotic twin pregnancies identified, completed follow-up data were available and analyzed for 855 patients (79.9%). Among those, 250 (29.2%) were 2-to-1 singletons and 605 (70.8%) were ongoing twins. Reduced singleton patients were slightly older, more likely white, and had lower body mass index. They were also more likely to have undergone in vitro fertilization (63.6% vs 48.8%), had chorionic villus sampling (92% vs 37.5%), and had prior term births (54% vs 35.7%). Compared with 2-to-1 singletons, the adjusted odds of having preterm delivery at 37 weeks for ongoing twins were 5.62 times (95% confidence interval, 3.67-8.61; P < .001) and 2.22 times (95% confidence interval, 1.20-4.11; P < .001) at 34 weeks. While intrauterine growth restriction, placental abruption, and gestational diabetes were not significant, ongoing twins were more likely to have a cesarean delivery (odds ratio, 5.53, 95% confidence interval, 3.60-8.49; P < .001) and preeclampsia (odds ratio, 3.33, 95% confidence interval, 1.60-6.96; P < .001) after adjusting for maternal characteristics. There were also significant differences between groups for preterm premature rupture of membranes and low birthweight at less than the fifth and 10th percentiles. Total pregnancy loss (at 24 and 20 weeks) was similar between singleton and ongoing twins (4% vs 2.5%, P = .23, and 3.6% vs 1.7%, P = .09 for respective weeks). There were no significant differences in the rate of unintended pregnancy loss (2.4% vs 2.3%; P = .94) and the rate of intrauterine fetal death greater than 24 weeks (1.2% vs 0.7%; P = .43) in reduced singleton versus ongoing twin group, respectively.

CONCLUSION

In our study, patients who elected to reduce to a singleton pregnancy had a higher gestational age of delivery and lower rates of preterm birth and pregnancy complications without an increased risk of pregnancy loss.

Trend in cesarean delivery rate among twin pregnancies over a 20 years epoch and the accompanied maternal and perinatal outcomes

Objective

To examine the trend of cesarean delivery (CD) rate among twin pregnancies and the trend in maternal and neonatal morbidities within two decades.

Study design

Population-based cohort study, conducted at a single teaching hospital in Israel on data between January 1995 and December 2015. All pregnant women with twin gestation who delivered at a gestational age of 24 weeks or more were included. Data on mode of deliveries, Apgar score <7 at 5 min, cord artery pH < 7.1, early postpartum hemorrhage, blood transfusion, and intrapartum fever for each year were extracted and plotted, and trends were analyzed. CDs performed for one or both twins were divided to laboring, i.e., after a trial of labor, and non-laboring CDs. Data was obtained from the hospital discharge register with ICD-9 codes and crosschecked with the labor medical records. The Cochran-Armitage Trend Test was used to identify trends and correlations.

Results

Of all 88,145 deliveries that took place during this period, 1955 (2.2%) were twins. Of these 53 were ineligible and were excluded. There was a statistically significant trend (increase) in twins birth over time (p = 0.004). CD rate increased significantly from 43.4% in 1995 to 66.0% in 2015 (p = 0.001). This increase was observed only among non-laboring cesareans (p = 0.001). Multivariate logistic regression analysis revealed that maternal and early neonatal morbidities examined did not differ significantly during the study period.

Conclusion

Non-laboring CD rate increased significantly over the past two decades among twin pregnancies. Despite this increase, maternal and early neonatal morbidities did not change.

Trial of labor after cesarean delivery in twin gestations: systematic review and meta-analysis

BACKGROUND

Trial of labor after cesarean is offered as a routine option for singleton gestations with previous cesarean delivery. However, adequate data are not available to determine whether the approach is equally valid in women with twin gestation.

OBJECTIVE

This systematic review and meta-analysis aimed to assess maternal morbidities associated with trial of labor after cesarean delivery in twin gestations.

STUDY DESIGN

Electronic databases were searched for cohort studies and randomized controlled trials evaluating the association between trial of labor after cesarean delivery in twin gestations and pregnancy outcomes. Maternal mortality and severe morbidities, such as uterine rupture and hysterectomy, were compared between women who had trial of labor and women who had a planned repeat cesarean delivery. Pooled odds ratios were calculated using a random-effects model. Additional analyses were performed to compare trial of labor after cesarean outcomes in singleton and twin gestations.

RESULTS

Eleven cohort studies including a total of 8209 twin gestations with previous cesarean delivery were included in the present study. Of these gestations, 2484 were intended for planned vaginal birth and 5725 were intended for planned repeat cesarean delivery. The rate of uterine rupture in twin gestations was higher in the trial of labor after cesarean group than the elective cesarean group (odds ratio, 10.09, 95% confidence interval, 4.30-23.69, I² = 68%). However, no statistically significant difference was found in the rate of uterine rupture between twin and single gestations attempting trial of labor after cesarean delivery (odds ratio, 1.34, 95% confidence interval, 0.54-3.31, I² = 0%). Women who attempted a trial of labor after cesarean delivery with twins did not have an increased risk of uterine scar dehiscence, hemorrhage, blood transfusion, or neonatal morbidity and mortality compared with elective repeat cesarean delivery. Patients with twins had similar rates of successful vaginal delivery as patients with singletons (odds ratio, 0.85, 95% confidence interval, 0.61-1.18, I² = 36%).

CONCLUSION

This meta-analysis demonstrates that, although trial of labor with twins after previous cesarean delivery is associated with higher rates of uterine rupture compared with elective cesarean delivery, pregnancy outcomes and success rates are similar to a trial of labor after previous cesarean delivery in singleton gestations. Planned vaginal birth for women with twin gestation and previous cesarean delivery may be a safe alternative to a planned repeat cesarean.

Twin pregnancy and risk of postpartum hemorrhage

Objective: To identify maternal and peripartum characteristics in twin gestations that are associated with postpartum hemorrhage (PPH) in which one or more units of packed red blood cells (PRBCs) were either administered or recommended but declined (PPH + PRBC).Methods: This retrospective cohort study evaluated all women with twin gestations who delivered at greater than 23 weeks of gestational age at a single, tertiary medical center from 2011 to 2016. Patients were included if they had documentation of estimated blood loss (EBL) at delivery and complete inpatient medical records available for review. Patients with incomplete records or an intrauterine fetal demise of one or both twins were excluded. The primary outcome was PPH + PRBC. Secondary outcomes included PPH with delivery EBL ≥1500 ml, PPH with atony and uterotonic administration, PPH with maternal hemorrhagic morbidity (MHM), and PPH with severe maternal morbidity (SMM). MHM was a composite outcome defined as PPH associated with any of the following: atony requiring uterotonics, any PRBC transfusion (≥1 unit), uterine or hypogastric artery ligation, hysterectomy, compression sutures, intrauterine balloon tamponade, uterine artery embolization, and/or exploratory laparotomy. SMM was a composite outcome defined as PPH associated with any of the following: administration of ≥4 units of PRBC, administration of ≥2 units of PRBC, and ≥2 units of fresh frozen plasma (FFP), return to operating room for any major procedure (excludes dilation and curettage), any peripartum hysterectomy, uterine artery embolization, intrauterine balloon tamponade or compression suture placed and administration of ≥2 units of PRBC, and/or intensive care unit (ICU) admission for invasive monitoring/treatment. A multivariable logistic regression analysis was performed.Results: A total of 1081 women with twin gestations were included. PPH + PRBC occurred in 4.4% (n = 48), delivery EBL ≥1500 ml occurred in 3.9% (n = 42), and atony with uterotonic administration occurred in 12.1% (n = 131) of the study population. The rate of MHM and SMM were 13.9% (n = 150) and 1.9% (n = 20), respectively. Although the rate of cesarean delivery was high overall (83.2%), it was nearly universal in the PPH + PRBC group (97.9%; p < .02). PPH + PRBC occurred at a rate of 0.5% (n = 1/182) among vaginally delivered twins compared to 5.2% (n = 47/899) among those delivered by cesarean (p < .03). The final multivariable logistic regression model to predict PPH + PRBC identified six significant maternal and peripartum factors: nulliparity, either pregestational or gestational diabetes, intrapartum magnesium sulfate, admission hematocrit <30%, admission platelets <100 000/µL and administration of general anesthesia.Conclusions: A number of maternal and peripartum factors are associated with PPH in twin gestations. Optimization of maternal hematologic parameters and chronic medical conditions, and reduction in the rate of cesarean delivery in twin pregnancies may decrease the risk of postpartum hemorrhage.

The frequency and clinical significance of intra-amniotic inflammation in twin pregnancies with preterm labor and intact membranes

OBJECTIVE

The objective of this study is to evaluate the frequency and clinical significance of intra-amniotic inflammation in twin pregnancies with preterm labor and intact membranes.

STUDY DESIGN

Amniotic fluid (AF) was retrieved from both sacs in 90 twin gestations with preterm labor and intact membranes (gestational age between 20 and 34 6/7 weeks). Preterm labor was defined as the presence of painful regular uterine contractions, with a frequency of at least 2 every 10 min, requiring hospitalization. Fluid was cultured and assayed for matrix metalloproteinase-8. Intra-amniotic inflammation was defined as an AF matrix metalloproteinase-8 concentration >23 ng/mL.

RESULTS

The prevalence of intra-amniotic inflammation for at least 1 amniotic sac was 39% (35/90), while that of proven intra-amniotic infection for at least one amniotic sac was 10% (9/90). Intra-amniotic inflammation without proven microbial invasion of the amniotic cavity was found in 29% (26/90) of the cases. Intra-amniotic inflammation was present in both amniotic sacs for 22 cases, in the presenting amniotic sac for 12 cases, and in the non-presenting amniotic sac for one case. Women with intra-amniotic inflammation observed in at least one amniotic sac and a negative AF culture for microorganisms had a significantly higher rate of adverse pregnancy outcome than those with a negative AF culture and without intra-amniotic inflammation (lower gestational age at birth, shorter amniocentesis-to-delivery interval, and significant neonatal morbidity). Importantly, there was no significant difference in pregnancy outcome between women with intra-amniotic inflammation and a negative AF culture and those with a positive AF culture.

CONCLUSION

Intra-amniotic inflammation is present in 39% of twin pregnancies with preterm labor and intact membranes and is a risk factor for impending preterm delivery and adverse outcome, regardless of the presence or absence of bacteria detected using cultivation techniques.

Neonatal morbidity associated with vaginal delivery of noncephalic second twins

BACKGROUND

Management of noncephalic second twin delivery rests on the results of population-based retrospective studies of twin births that have shown higher neonatal mortality and morbidity for second twins with noncephalic, compared with cephalic, presentations after vaginal delivery of the first twin. Because these studies are flawed by data of questionable validity, do not report the obstetrical practices at delivery, and do not allow collection of potential confounding variables, we performed a national prospective study specially designed to evaluate the management of twins' delivery.

OBJECTIVE

We sought to assess neonatal mortality and morbidity according to second twin presentation after vaginal birth of the first twin.

STUDY DESIGN

The Jumeaux Mode d'Accouchement study was a nationwide prospective population-based cohort study of twin deliveries performed in 176 maternity units in France from February 2014 through March 2015. The primary outcome was a composite of intrapartum mortality and neonatal mortality and morbidity. Neonatal outcomes of second twins born ≥32 weeks of gestation after vaginal delivery of the first cephalic or breech twin were compared according to the noncephalic or cephalic second twin presentation. Multivariable logistic regression models controlled for potential confounders. Subgroup analyses were conducted according to the breech or transverse presentation of the noncephalic second twin, and gestational age at delivery, before or after 37 weeks of gestation.

RESULTS

Among 3903 second twins enrolled in the study, 2384 (61.1%) were in cephalic and 1519 (38.9%) in noncephalic presentations, of whom 999 (25.6%) were in breech and 520 (13.3%) in transverse presentation. Composite neonatal mortality and morbidity did not differ between the noncephalic and cephalic group (47/1519 [3.1%] vs 59/2384 [2.5%]; adjusted odds ratio, 1.23; 95% confidence interval, 0.81-1.85). No significant difference between groups was shown for the primary outcome in subgroup analyses according to type of noncephalic second twin presentation or gestational age at delivery. Cesarean delivery rates for the second twin were lower in the breech than in the cephalic group (14/999 [1.4%] vs 75/2384 [3.1%], P = .003) and lower in the cephalic than in the transverse group (75/2384 [3.1%] vs 35/520 [6.7%], P < .001).

CONCLUSION

Noncephalic and cephalic second twin presentations after vaginal delivery of the first twin ≥32 weeks of gestation are associated with similar low composite neonatal mortality and morbidity. Vaginal delivery of noncephalic second twin is a reasonable option.

Epidemiology of Periviable Births: The Impact and Neonatal Outcomes of Twin Pregnancy

This article discusses a study that estimated the prevalence of twin live births in the United States that were delivered in the periviable (20-25 weeks) gestational age, and compared changes in twin neonatal mortality and morbidity rates between 2005 and 2013 overall, and at periviable gestations. Although the decline in twin neonatal mortality rates at 23 and 24 weeks is encouraging, and suggests advancement in the neonatal care of these extremely small twins, the concomitant increase in neonatal morbidity at 23 weeks is concerning. Efforts to understand if twins delivered at periviable gestations suffer from long-term consequences of neurodevelopmental and cognitive deficits remain important.