General Obstetrics and Gynecology: Obstetrics
Neonatal mortality and morbidity rates in term twins with advancing gestational age

https://doi.org/10.1016/j.ajog.2006.01.018Get rights and content

Objective

The purpose of this study was to identify the gestational age with the lowest morbidity and mortality rates for twin pregnancies that reach term.

Study design

A retrospective cohort study carried out with 60,443 twin pairs from the United States (1995-1997). Analysis was restricted to pregnancies that had reached at least 37 weeks of gestation; groups were created on the basis of the gestational ages of 37, 38, 39, and ≥40 weeks. The incidence of death and morbidity were calculated; multiple logistic regression models were used to estimate the independent effect of gestational age for twin A and B.

Results

The neonatal mortality rate increased significantly after 40 weeks of gestation (twin A: odds ratio, 3.47 [95% CI, 2.29, 5.38]; twin B, odds ratio, 2.52 [95% CI, 1.75, 3.67]). There was also an increased risk of neonatal morbidity in the ≥40 weeks of gestation group for twin A and B (Apgar score, ≤3; odds ratio, 1.88 [95% CI, 1.18, 3.02], 1.74 [95% CI, 1.21, 2.52], respectively). There was a decreased risk of assisted ventilation in the 38 and 39 weeks of gestation group for twin A (odds ratio, 0.86 [95% CI, 0.77, 0.97], odds ratio, 0.83 [95% CI, 0.72, 0.95], respectively) and a decreased risk in the 39 and ≥40 weeks of gestation groups for twin B (assisted ventilation: odds ratio, 0.83 [95% CI, 0.73, 0.93], odds ratio, 0.81 [95% CI, 0.72, 0.92], respectively).

Conclusion

This study suggests that the optimal date of delivery for twins should be <40 weeks of gestation; there was no compelling evidence for delivering at <38 weeks of gestation.

Section snippets

Material and methods

A population-based retrospective cohort study was carried out with twin registry data (1995-1997) from the United States using the Matched Multiple Birth File created by the Centers for Disease Control and Prevention. Sets of multiple births in the 1995 through 1997 birth files were matched by plurality, state and country of occurrence of delivery, mother's date of birth, date of last menstrual period, number of prenatal visits, level of education, weight gain during pregnancy, and date of

Results

There were 152,233 twin pairs in the database. Of which, 18,689 twin pairs were excluded because of a missing value on birth order, and 2480 pairs were excluded because of a missing value or apparent coding error (first twin cesarean delivery but second twin vaginal delivery) on mode of delivery. There were 70,621 twins excluded because they were delivered at <37 completed weeks of gestation, which left 60,443 twin pairs for analysis.

From Table I, it can be seen that a significant difference

Comment

There was an increased incidence of total neonatal and noncongenital anomaly-related deaths in the ≥40 weeks of gestation group when compared with the 37 weeks of gestation group for both twin A and B. When morbidity was examined, there was an increased risk of having a low Apgar score for the ≥40 weeks of gestation group for both twin A and B. In regards to the need of assisted ventilation, there was a decreased risk in the 38 and 39 weeks of gestation group for twin A and a decreased risk in

References (16)

There are more references available in the full text version of this article.

Cited by (25)

  • Optimizing Term Delivery and Mode of Delivery

    2020, Clinics in Perinatology
    Citation Excerpt :

    In a study by Soucie and colleagues71 (2006) it was found that the risk of neonatal respiratory complications requiring ventilatory support decreases after 38 weeks. This study also identified significant risk of neonatal death with DCDA pregnancies extending after 40 weeks.71 A randomized controlled trial of uncomplicated twin pregnancies (including both monochorionic and dichorionic gestations) comparing delivery at 37 versus 38 weeks noted no difference in composite adverse infant outcomes.72

  • Second twin delivery in cephalic presentation. Apropos of a series of 127 patients

    2016, Journal de Gynecologie Obstetrique et Biologie de la Reproduction
  • Medical care and perinatal health in twin pregnancies: Situation in 2010 and recent trends in France

    2015, Journal de Gynecologie Obstetrique et Biologie de la Reproduction
View all citing articles on Scopus
View full text