Delivery of the term twin

Cesarean delivery or induction of labor in pre-labor twin gestations: a secondary analysis of the twin birth study

Background

In the Twin Birth Study, women at 32^0/7–38^6/7 weeks of gestation, in whom the first twin was in cephalic presentation, were randomized to planned vaginal delivery or cesarean section. The study found no significant differences in neonatal or maternal outcomes in the two planned mode of delivery groups. We aimed to compare neonatal and maternal outcomes of twin gestations without spontaneous onset of labor, who underwent induction of labor or pre-labor cesarean section as the intervention of induction may affect outcomes.

Methods

In this secondary analysis of the Twin Birth Study we compared those who had an induction of labor with those who had a pre-labor cesarean section. The primary outcome was a composite of fetal or neonatal death or serious neonatal morbidity. Secondary outcome was a composite of maternal morbidity and mortality. Trial Registration: NCT00187369.

Results

Of the 2804 women included in the Twin Birth Study, a total of 1347 (48%) women required a delivery before a spontaneous onset of labor occurred: 568 (42%) in the planned vaginal delivery arm and 779 (58%) in the planned cesarean arm. Induction of labor was attempted in 409 (30%), and 938 (70%) had a pre-labor cesarean section. The rate of intrapartum cesarean section in the induction of labor group was 41.3%. The rate of the primary outcome was comparable between the pre-labor cesarean section group and induction of labor group (1.65% vs. 1.97%; p = 0.61; OR 0.83; 95% CI 0.43–1.62). The maternal composite outcome was found to be lower with pre-labor cesarean section compared to induction of labor (7.25% vs. 11.25%; p = 0.01; OR 0.61; 95% CI 0.41–0.91).

Conclusion

In women with twin gestation between 32^0/7–38^6/7 weeks of gestation, induction of labor and pre-labor cesarean section have similar neonatal outcomes. Pre-labor cesarean section is associated with favorable maternal outcomes which differs from the overall Twin Birth Study results. These data may be used to better counsel women with twin gestation who are faced with the decision of interventional delivery.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12884-020-03369-x.

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.

Obstetric Outcomes of Twin Pregnancies in Japanese Women Aged 40 and Older

Background

The aim of this study was to compare the obstetric outcomes of twin pregnancies between Japanese women aged ≥ 40 years and their younger counterparts aged 25 - 29.

Methods

This was a retrospective study of twin pregnancies managed at Japanese Red Cross Katsushika Maternity Hospital between 2002 and 2016. Women aged 40 and older at delivery (n = 117) were compared with women aged 25 - 29 at delivery (n = 536).

Results

Although the women ≥ 40 years old were more likely to have increased risks of HELLP (hemolytic, elevated liver enzymes and low platelet) syndrome and very low birth weight neonates, there were no measurable differences in obstetric outcomes such as hypertensive disorders, premature delivery and neonatal asphyxia between the two groups.

Conclusion

Advanced maternal age did not seem to affect obstetric outcomes in twin pregnancies seriously.

Safety of vaginal delivery among dichorionic diamniotic twins over 10 years in a UK teaching hospital

OBJECTIVE

To determine whether vaginal delivery among dichorionic diamniotic twins remains a safe option following full implementation of the European Working Time Directive in the UK.

METHODS

A retrospective study was conducted using data for women with dichorionic diamniotic twin pregnancies who attended a teaching hospital in London, UK, for delivery between January 4, 2000, and December 23, 2010.

RESULTS

Among 892 women, 474 (53.1%) attempted vaginal delivery, 220 (46.4%) of whom achieved spontaneous vaginal delivery of both twins. Instrumental vaginal delivery was performed among 89 women (18.8%), and 165 (34.8%) women underwent emergency cesarean delivery. Delivery of the second twin by emergency cesarean (n=31) was predominantly for fetal distress (13 [41.9%]) or abnormal lie (10 [32.3%]). A 5-minute Apgar score of 9 or 10 was recorded for 384 (83.7%) of 459 first twins and 369 (82.9%) of 445 second twins, irrespective of the mode of delivery.

CONCLUSION

Vaginal delivery among dichorionic diamniotic twins had a good success rate and a low intrapartum emergency cesarean delivery rate. Training in cardiotocography and intrapartum procedures might further reduce the need for emergency cesarean delivery.

Planned caesarean section for women with a twin pregnancy

BACKGROUND

Twin pregnancies are associated with increased perinatal mortality, mainly related to prematurity, but complications during birth may contribute to perinatal loss or morbidity. The option of planned caesarean section to avoid such complications must therefore be considered. On the other hand, randomised trials of other clinical interventions in the birth process to avoid problems related to labour and birth (planned caesarean section for breech, and continuous electronic fetal heart rate monitoring), have shown an unexpected discordance between short-term perinatal morbidity and long-term neurological outcome. The risks of caesarean section for the mother in the current and subsequent pregnancies must also be taken into account.

OBJECTIVES

To determine the short- and long-term effects on mothers and their babies, of planned caesarean section for twin pregnancy.

SEARCH METHODS

We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (18 November 2015) and reference lists of retrieved studies.

SELECTION CRITERIA

Randomised trials comparing a policy of caesarean section with planned vaginal birth for women with twin pregnancy.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed eligibility, quality and extracted data. Data were checked for accuracy. For important outcomes the quality of the evidence was assessed using the GRADE approach.

MAIN RESULTS

We included two trials comparing planned caesarean section versus planned vaginal birth for twin pregnancies.Most of the data included in the review were from a multicentre trial where 2804 women were randomised in 106 centres in 25 countries. All centres had facilities to perform emergency caesarean section and had anaesthetic, obstetrical, and nursing staff available in the hospital at the time of planned vaginal delivery. In the second trial carried out in Israel, 60 women were randomised. We judged the risk of bias to be low for all categories except performance (high) and outcome assessment bias (unclear).There was no clear evidence of differences between women randomised to planned caesarean section or planned vaginal birth for maternal death or serious morbidity (risk ratio (RR) 0.86, 95% confidence interval (CI) 0.67 to 1.11; 2844 women; two studies; moderate quality evidence). There was no significant difference between groups for perinatal or neonatal death or serious neonatal morbidity (RR 1.15, 95% CI 0.80 to 1.67; data for 5565 babies, one study, moderate quality evidence). No studies reported childhood disability.For secondary outcomes there was no clear evidence of differences between groups for perinatal or neonatal mortality (RR 1.41, 95% CI 0.76 to 2.62; 5685 babies; two studies, moderate quality evidence), serious neonatal morbidity (RR 1.03, 95% CI 0.65 to 1.64; 5644 babies; two studies, moderate quality evidence) or any of the other neonatal outcomes reported.The number of women undergoing caesarean section was reported in both trials. Most women in the planned caesarean group had treatment as planned (90.9% underwent caesarean section), whereas in the planned vaginal birth group 42.9% had caesarean section for at least one twin. For maternal mortality; no events were reported in one trial and two deaths (one in each group) in the other. There were no significant differences between groups for serious maternal morbidity overall (RR 0.86, 95% CI 0.67 to 1.11; 2844 women; two studies) or for different types of short-term morbidity. There were no significant differences between groups for failure to breastfeed (RR 1.14, 95% CI 0.95 to 1.38; 2570 women, one study; moderate quality evidence) or the number of women with scores greater than 12 on the Edinbugh postnatal depression scale (RR 0.95, 95% CI 0.78 to 1.14; 2570 women, one study; moderate quality evidence).

AUTHORS' CONCLUSIONS

Data mainly from one large, multicentre study found no clear evidence of benefit from planned caesarean section for term twin pregnancies with leading cephalic presentation. Data on long-term infant outcomes are awaited. Women should be informed of possible risks and benefits of labour and vaginal birth pertinent to their specific clinical presentation and the current and long-term effects of caesarean section for both mother and babies. There is insufficient evidence to support the routine use of planned caesarean section for term twin pregnancy with leading cephalic presentation, except in the context of further randomised trials.

Planned caesarean section for women with a twin pregnancy

BACKGROUND

Twin pregnancies are associated with increased perinatal mortality, mainly related to prematurity, but complications during birth may contribute to perinatal loss or morbidity. The option of planned caesarean section to avoid such complications must therefore be considered. On the other hand, randomised trials of other clinical interventions in the birth process to avoid problems related to labour and birth (planned caesarean section for breech, and continuous electronic fetal heart rate monitoring), have shown an unexpected discordance between short-term perinatal morbidity and long-term neurological outcome. The risks of caesarean section for the mother in the current and subsequent pregnancies must also be taken into account.

OBJECTIVES

To determine the short- and long-term effects on mothers and their babies, of planned caesarean section for twin pregnancy.

SEARCH METHODS

We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (30 September 2011).

SELECTION CRITERIA

Randomised trials comparing a policy of caesarean section with planned vaginal birth for women with twin pregnancy.

DATA COLLECTION AND ANALYSIS

Two researchers independently assessed eligibility, quality and extracted data. Data were checked for accuracy.

MAIN RESULTS

One small trial with unconfirmed allocation concealment compared caesarean section with planned vaginal birth in 60 women with vertex/non-vertex twin pregnancies. There were no differences in perinatal outcome. The trial was too small to exclude the possibility of clinically meaningful benefits of either approach. There is one additional trial currently ongoing.

AUTHORS' CONCLUSIONS

There is a lack of robust evidence to guide clinical advice regarding the method of birth for twin pregnancies. Women should be informed of possible benefits and risks of either approach, including short-term and long-term consequences for both mother and babies. Future research should aim to provide unbiased evidence, including long-term outcomes.

Ophthalmic phenotypes and the representativeness of twin data for the general population

PURPOSE

To compare the distributional parameters for a series of ocular biometric traits between twins and their singleton siblings, to evaluate the generalizability of twin data, as used in heritability analyses to the general population.

METHODS

A series of birth, anthropometric, and 13 ocular biometric traits were selected for analysis: interpupillary distance (IPD), visual acuity (logMAR), spherical equivalent refractive error, corneal curvature, axial length, anterior chamber depth (ACD), central corneal thickness (CCT), intraocular pressure (IOP), optic disc, cup and rim areas, and measures of retinal vessel caliber; central retinal arteriolar equivalent (CRAE), and central retinal venular equivalent (CRVE). Structural equation modeling was used to test the assumption that the means and variances for each trait did not differ between twins and their siblings.

RESULTS

Significant differences in log-likelihood for birth weight and gestational age were observed between twins and siblings, with the latter being both heavier and closer to full-term at birth. Siblings were also found to have larger IPD and axial length, and better visual acuity compared with their twin counterparts. Refractive error, corneal curvature, ACD, CCT, optic disc parameters, and retinal vascular calibers did not differ significantly between the two groups.

CONCLUSIONS

Twins are representative of the general population for some but not all measures of ocular biometry. Consequently, care should be taken when extrapolating twin data for these traits in heritability and other genetic studies. Birth weight differences between twins and siblings do not appear to account for the differences in ocular biometry observed in this study.

Vaginal delivery of vertex-nonvertex twins: a fading skill?

BACKGROUND

Delivery of the second twin is one of the most challenging events for practicing obstetricians. Due to the increased incidence of twin gestations and lack of well-designed clinical trials, evidence-based recommendations are lagging behind clinical demand.

OBJECTIVE

The present review examines the practice of second nonvertex twin deliveries.

METHODS

A review of the literature was conducted using the term vertex-nonvertex; twin gestation; mode of delivery; and cesarean delivery.

RESULTS

There is a lack of evidence supporting the appropriate approach to second nonvertex twin deliveries. Larger studies with increased power are needed to examine the variations regarding gestational period, birth weight, and institutional experience. In the mean time, unless otherwise contraindicated, it is reasonable to attempt vaginal delivery and total breech extraction and proceed to assisted delivery or cesarean delivery if unsuccessful.

CONCLUSIONS

Preserving the art of obstetric maneuvering is important as well for twin deliveries. In cases of vertex-nonvertex presentation, vaginal delivery is preferred in certain conditions.

Twin deliveries and place of birth in NSW 2001-2005

BACKGROUND

Twin pregnancies have an elevated risk of adverse outcomes, particularly preterm twins.

AIMS

Describe the distribution of twin deliveries by hospital level, the associated perinatal and maternal morbidity, and determine predictors of perinatal morbidity and urgent transfer to a neonatal intensive care unit.

METHODS

Longitudinally linked New South Wales delivery and hospital records for the years 2001-2005 were used to identify perinatal and maternal morbidity/mortality in twin pregnancies. Regression analysis was used to examine predictive factors, including birth hospital volume.

RESULTS

At < or = 32 weeks, 88.1% of twins were delivered in tertiary referral hospitals. By 34-35 weeks, only 39.7% of twins were delivered in tertiary units. Gestational age was the primary predictor of perinatal morbidity/mortality. Perinatal morbidity/mortality and maternal morbidity were lowest for deliveries at 38 weeks. There was no evidence that planned caesarean section at < or = 38 weeks was protective against perinatal morbidity/mortality. There was an increased risk of perinatal morbidity/mortality (odds ratio (OR) = 2.22) for twins delivered at 33-35 weeks gestation at hospitals with < 500 deliveries per annum, and an increased risk of urgent neonatal transfer (OR = 2.06). Twin pairs for whom there was a > or = 20% discordance in birthweight had an increased risk of morbidity/mortality at 36-38 weeks (OR = 1.79).

CONCLUSIONS

Both infant and maternal morbidity increase from 39 weeks gestation. Delivery of twins before 36 weeks at smaller hospitals (< 500 deliveries per annum) should be avoided. A twin pregnancy where there is a > or = 20% difference in estimated fetal weights should be considered for referral to a tertiary obstetric unit.

Infant morbidity and mortality associated with vaginal delivery in twin gestations

OBJECTIVE

To compare infant outcomes for twin gestations delivered vaginally with those with cesarean delivery by using a large national dataset containing birth certificate data.

STUDY DESIGN

Vertex/vertex presenting twins delivering at >/= 30 weeks' gestation were separated by method of delivery and compared for neonatal morbidities and death in the first year of life. Similar comparisons were performed for vertex/nonvertex presenting twins.

RESULTS

For vertex/vertex presenting twins, vaginal delivery was not associated with an increase in composite morbidity or mortality compared with cesarean birth. For vertex/nonvertex presenting twins, vaginal delivery was associated with small increases in the incidences of 5-minute Apgar scores </= 3, ventilation for < 30 minutes, and birth injury but not seizures or infant death. When the birthweight of the second twin exceeded that of the first by 25% or more, excess morbidity with vaginal delivery was not seen.

CONCLUSION

For both vertex/vertex and vertex/nonvertex presentations, morbidity and mortality are similar for vaginal and cesarean deliveries of twin gestations at or beyond 30 weeks' gestation.

Twin gestation and neurodevelopmental outcome in extremely low birth weight infants

OBJECTIVE

The purpose of this work was to compare the risk-adjusted incidence of death or neurodevelopmental impairment at 18 to 22 months' corrected age between twin and singleton extremely low birth weight infants. We hypothesized that twin gestation is independently associated with increased risk of death or adverse neurodevelopmental outcomes at 18 to 22 months' corrected age in these infants.

METHODS

We conducted a retrospective study of inborn extremely low birth weight infants admitted to Eunice Kennedy Shriver National Institute of Child Health and Human Development Neonatal Research Network units between 1997 and 2005, who either died or had follow-up data available at 18 to 22 months' corrected age. Neurodevelopmental impairment, the primary outcome variable, was defined as the presence of any 1 of the following: moderate or severe cerebral palsy, severe bilateral hearing loss, bilateral blindness, Bayley Mental Developmental Index or Psychomotor Developmental Index of <70. Death was included with neurodevelopmental impairment as a composite outcome. Results were compared for both twins, twin A, twin B, same-gender twins, unlike-gender twins, and singleton infants. Logistic regression analysis was performed to control for demographic and clinical factors that were different among the groups.

RESULTS

The cohort of infants who either died or were assessed for neurodevelopmental impairment consisted of 7630 singleton infants and 1376 twins. Logistic regression adjusting for clinical and sociodemographic risk factors showed an increased risk of death or neurodevelopmental impairment for twins as a group when compared with the singletons. On analyzing twin A and B separately as well, risk of death or neurodevelopmental impairment was increased in both twin A and twin B.

CONCLUSIONS

Twin gestation in extremely low birth weight infants is associated with an independent increased risk of death or neurodevelopmental impairment at 18 to 22 months' corrected age compared with singleton-gestation infants. Both first- and second-born twins are at increased risk.

Preterm birth in twins after subfertility treatment: population based cohort study

OBJECTIVES

To assess gestational length and prevalence of preterm birth among medically and naturally conceived twins; to establish the role of zygosity and chorionicity in assessing gestational length in twins born after subfertility treatment.

DESIGN

Population based cohort study.

SETTING

Collaborative network of 19 maternity facilities in East Flanders, Belgium (East Flanders prospective twin survey).

PARTICIPANTS

4368 twin pairs born between 1976 and 2002, including 2915 spontaneous twin pairs, 710 twin pairs born after ovarian stimulation, and 743 twin pairs born after in vitro fertilisation or intracytoplasmic sperm injection.

MAIN OUTCOME MEASURES

Gestational length and prevalence of preterm birth.

RESULTS

Compared with naturally conceived twins, twins resulting from subfertility treatment had on average a slightly decreased gestational age at birth (mean difference 4.0 days, 95% confidence interval 2.7 to 5.2), corresponding to an odds ratio of 1.6 (1.4 to 1.8) for preterm birth, albeit confined to mild preterm birth (34-36 weeks). The adjusted odds ratios of preterm birth after subfertility treatment were 1.3 (1.1 to 1.5) when controlled for birth year, maternal age, and parity and 1.6 (1.3 to 1.8) with additional control for fetal sex, caesarean section, zygosity, and chorionicity. Although an increased risk of preterm birth was therefore seen among twins resulting from subfertility treatment, the risk was largely caused by a first birth effect among subfertile couples; conversely, the risk of prematurity was substantially levelled off by the protective effect of dizygotic twinning.

CONCLUSIONS

Twins resulting from subfertility treatment have an increased risk of preterm birth, but the risk is limited to mild preterm birth, primarily by virtue of dizygotic twinning.

Intrapartum management of twins: truths and controversies

Twin gestations pose a challenge in management, and the intrapartum phase of care is not exempt. Despite increasing numbers of twin gestations, the literature does not adequately answer several basic questions regarding appropriate intrapartum management. This article provides an overview of the available literature supporting appropriate intrapartum actions in twin gestations and highlights areas that are still awaiting further study, with the eventual goal of optimizing intrapartum conditions, leading to an improved neonatal outcome.