Timing of birth in multiple pregnancy

Chorionicity, birth weight discordance and neonatal morbidity in uncomplicated twin pregnancies delivered from 36 weeks

OBJECTIVES

To investigate the association between chorionicity, birth weight discordance and neonatal morbidity in uncomplicated twin pregnancies progressing to at least 36 weeks of gestation.

STUDY DESIGN

This was a retrospective single centre cohort study of all twin pregnancies referred to our twin clinic between 2011 and 2018. Outcome details were obtained from the computerized maternity and neonatal records. The primary outcome was incidence of composite neonatal morbidity according to chorionicity. We also determined the incidence of composite neonatal morbidity in pregnancies with birth weight discordance. Logistic regression was used to identify and adjust for potential confounders.

RESULTS

Three hundred and eighty-five twin pregnancies (286 dichorionic, 99 monochorionic) were included. Gestational age at birth was significantly lower in pregnancies complicated by neonatal morbidity (p = 0.013) compared with those which were not. On multivariable logistic regression analysis, gestational age at birth (p = 0.031) and birth weight discordance (p = 0.004), but not chorionicity (p = 0.626) were independently associated with neonatal morbidity.

CONCLUSION(S)

In uncomplicated twin pregnancies chorionicity is not associated with neonatal morbidity. Gestational age at birth is the major determinant of neonatal outcome while the clinical impact of weight discordance seems marginally significant.

Twins versus singleton pregnancies: outcomes in small for gestational age late preterm deliveries

Background: Compared to singleton pregnancies, small for gestational age (SGA) and twin gestations experience adverse maternal and neonatal outcomes. Specific data regarding outcomes in late preterm SGA twin gestations are lacking.Objective: This study sought to compare pregnancy outcomes of late preterm (≥34 and <37 weeks) SGA twins versus singletons. In addition, we sought to stratify the comparisons by <10 and <5 percentile categories.Study design: In this retrospective cohort of 1.85 million pregnancies, we identified 10,646 nonanomalous, SGA, late preterm singleton and twin pregnancies. Births at gestational ages <34 and ≥37 weeks were excluded. Multivariate regression analyses and Chi-squared test were used for statistical comparisons and a p-value of less than 0.05 was used to indicate statistical significance.Results: After controlling for race, education, parity, prenatal care, diabetes, and hypertensive disease, twin pregnancies were less likely to experience neonatal death (aOR 0.14; 95% CI 0.03-0.63; p = .01) and intrauterine fetal demise (IUFD) (aOR 0.16; 95% CI 0.08-0.31; p < .001) compared to SGA <10 percentile singletons. Cesarean rates were higher in SGA <10 [percentile twin pregnancies (aOR 3.40; 95% CI 3.01-3.90; p < .001) as were postpartum hemorrhage (aOR 2.01; 95% CI 1.52-2.67; p < .001) and transfusion (aOR 1.54; 95% CI 1.52-2.67; p = .024).Conclusion: Late preterm SGA twin pregnancies were more like to be complicated by cesarean delivery, postpartum hemorrhage, and maternal transfusion compared to singleton pregnancies. However, neonatal death and IUFD were less common in SGA twin gestations.

Birth management and fetal outcome in multiple gestation: analysis of 1.444 births

PURPOSE

Since the late 1990s, controversies came up concerning the mode of delivery for multiples births. The twin birth study indicated no difference in maternal and fetal outcome between planned vaginal delivery and planned caesarean section, but did not analyze the influence of maternal and fetal characteristics or the obstetric management in vaginal birth. The purpose of this study is to analyze these parameters regarding fetal outcome.

METHODS

A large-scale retrospective analysis of twin births (n = 1.444) was performed at a university medical center. The analysis included pregnancy, delivery, and maternal and fetal parameters, including pH and base excess (BE) differences between the first- and second-born twin (delta pH, delta BE).

RESULTS

Delta pH correlated significantly with the birth interval for various positions of twins in the womb (p < 0.05). The longer the birth interval, the greater the delta pH with a lower pH of the second twin. Delta BE values were significantly correlated with the birth interval for a combination of twins in cephalic and breech presentation. Furthermore, it could be shown that higher differences in birth weight between the first/second twin are associated with higher delta pH, higher delta BE values (all p < 0.05). We found significantly decreasing delta pH values in vaginal deliveries over secondary and, finally, primary caesarean sections (p < 0.001).

CONCLUSION

We conclude a vaginal delivery of twin appears safe if experienced staff monitor birth weight discrepancies, birth interval, and blood values consequently. A good outcome also for the second twin delivered spontaneously is nevertheless feasible if experienced staff is available.

Neonatal outcomes of twin pregnancies delivered at late-preterm versus term gestation based on chorionicity and indication for delivery

OBJECTIVE

To investigate the neonatal outcomes of twin pregnancies delivered at late-preterm versus term gestation based on chorionicity and indication for delivery.

STUDY DESIGN

This is a retrospective cohort study of women with twin pregnancies delivered at ≥34 weeks of gestation from 1995 to 2014. Subjects were categorized into two groups according to gestational age at delivery: late-preterm group (34-36 weeks) and term group (≥37 weeks). Neonatal outcome measures including neonatal intensive care unit (NICU) admission, mechanical ventilator support, and respiratory distress syndrome (RDS) were compared between the late-preterm and term group based on chorionicity (monochorionic or dichorionic) and delivery indication (elective or non-elective).

RESULTS

A total of 1198 twin pregnancies were included in the study: 679 in the late-preterm group and 519 in the term group. Late-preterm twin infants had higher rates of NICU admission, mechanical ventilator support, and RDS than did term twin infants, regardless of the chorionicity and indication for delivery. In the multivariable analysis, late-preterm birth, monochorionicity, and non-elective delivery were independently associated with a significantly higher risk of NICU admission and mechanical ventilator support.

CONCLUSION

The late-preterm birth was associated with a higher risk of adverse neonatal outcome regardless of chorionicity and indication for delivery, and showed significantly increased risk by monochorionicity and non-elective delivery.

Gestational age at delivery and neonatal outcome in uncomplicated twin pregnancies: what is the optimal gestational age for delivery according to chorionicity?

Objective

To investigate the neonatal outcome according to the gestational age at delivery and to determine the optimal timing for delivery in uncomplicated monochorionic and dichorionic twin pregnancies.

Methods

This is a retrospective cohort study of women with uncomplicated twin pregnancies delivered at or beyond 35 weeks of gestation from 1995 to 2013. The primary outcome was neonatal composite morbidity, which was defined as when either one or both twins have one or more of the followings: fetal death after 35 weeks gestation, admission to neonatal intensive care unit, mechanical ventilator requirement, respiratory distress syndrome and neonatal death. To determine the optimal gestational age for delivery according to chorionicity, we compared the neonatal composite morbidity rate between women who delivered and women who remained undelivered at each gestational week in both monochorionic and dichorionic twin pregnancies.

Results

A total of 697 twin pregnancies were included (171 monochorionic and 526 dichorionic twins). The neonatal composite morbidity rate significantly decreased with advancing gestational age at delivery and its nadir was observed at 38 and ≥39 weeks of gestation in monochorionic and dichorionic twins, respectively. However, the composite morbidity rate did not differ between women who delivered and women who remained undelivered ≥36 and ≥37 weeks in monochorionic and dichorionic twins, respectively.

Conclusion

Our data suggest that the optimal gestational age for delivery was at ≥36 and ≥37 weeks in uncomplicated monochorionic and dichorionic twin pregnancies, respectively.

A population-based cohort study of stillbirth among twins in Lusaka, Zambia

OBJECTIVE

To determine rates of stillbirth and the associated risk factors for stillbirth among twins delivered in Lusaka, Zambia.

METHODS

A retrospective cohort analysis was conducted of singletons and twins delivered at 26 public sector facilities between February 1, 2006, and May 31, 2013. Data were obtained from the Zambian Electronic Perinatal Record System. Risk of stillbirth was estimated using logistic regression.

RESULTS

Overall, 260 657 singletons and 4021 twin pairs were included. There were 5105 stillbirths; 317 twins were stillborn. The crude stillbirth rate for twins was 39.4 per 1000 births (95% confidence interval [CI] 35.2-43.7) whereas the rate for singletons was 18.4 per 1000 births (95% CI 17.9-18.9; P<0.001). Factors associated with stillbirth among twins were increased interval between delivery (>60 minutes), low birth weight (<2500 g), birth order (being the second-born), and difference in birth weights (>30% discordance).

CONCLUSION

Twins were at an increased risk of stillbirth. Improved understanding of factors associated with stillbirth in this population could help to improve perinatal outcomes globally.

Clinical factors affecting the timing of delivery in twin pregnancies

OBJECTIVE

To investigate clinical factors affecting the timing of delivery in twin pregnancies in order to minimize perinatal complications.

METHODS

A retrospective study involved 163 twin pregnancies delivered from January 2006 to September 2011 at Gachon University Gil Medical Center. These cases were divided into three groups based on the delivery timing: less than 32 weeks' gestation (group A), between 32 and 35+6 weeks' gestation (group B), and over 36 weeks' gestation (group C). Clinical factors including maternal age, parity, presence of premature uterine contraction, presence of premature rupture of membrane, white blood cell, high sensitive C-reactive protein level, cervical dilatation, maternal complication, chorionicity, twin specific complication, and perinatal complication were analyzed for each group.

RESULTS

In group B, the timing of delivery was postponed for 14 days or more from the time of admission, and there were fewer numbers of babies with low Apgar score at birth compared with other groups. The frequency of uterine contraction (P<0.001), presence of premature rupture of membranes (P=0.017), dilatation of cervix (P<0.001), increased white blood cell and high sensitive C-reactive protein levels (P=0.002, P<0.001) were important clinical factors during decision making process of delivery timing in twin pregnancies. Twin specific fetal conditions, such as twin-twin transfusion syndrome and discordant growth (over 25% or more) were shown more frequently in group A. However, there were no significant statistical differences among three groups (P=0.06, P=0.14).

CONCLUSION

Proper management for preventing premature contraction and inflammation can be essential in twin pregnancies until 32 weeks' gestation, and may decrease maternal and perinatal complications.