Twins and triplets: The effect of plurality and growth on neonatal outcome compared with singleton infants

doi:10.1016/j.ajog.2004.03.040

American Journal of Obstetrics and Gynecology

Volume 191, Issue 3, September 2004, Pages 700-707

https://doi.org/10.1016/j.ajog.2004.03.040 Get rights and content

Abstract

Objective

Information on outcome by gestational age from large numbers of twins and triplets is limited and is important for counseling and decision-making in obstetric practice. We reviewed one of the largest available neonatal databases to describe mortality and morbidity rates and growth in newborn infants from multiple gestations and compared these data with data for singletons.

Study design

Data from a large prospectively recorded neonatal database that incorporated neonatal records from January 1997 to July 2002 were reviewed. We evaluated birth weight and neonatal mortality and morbidity rates that affected long-term outcome for each week of gestational age from 23 to 35 weeks of gestation for all nonanomolous inborn twins and triplets who were admitted to the neonatal intensive care unit and compared these data to all singletons who met similar criteria during the same time period.

Results

There were 12,302 twin and 2155 triplet births that met the entry criteria. The data for these newborn infants were compared with 36,931 singletons. Average birth weights at each gestational week were similar for all gestational ages until 29 weeks of gestation for triplets and 32 weeks of gestation for twins. After these gestational ages, the entire difference between twins and singletons was due to the weight of the smaller twin; the larger twins' mean weights were similar to singletons at all weeks that were studied. Birth order at each week also did not affect neonatal mortality rates, even when corrected for route of delivery and antenatal steroids. Neonatal morbidities associated with adverse long-term outcomes (intraventricular hemorrhage, retinopathy of prematurity, necrotizing enterocolitis) were also not different between multiple infants and singletons. Intrauterine growth restriction (IUGR) was associated with increased mortality rates at all gestational ages, but in the absences of IUGR, discordance was not.

Conclusion

Data on a large number of twins and triplets provide reassurance that neonatal outcome at all viable premature weeks of gestation are similar to singletons. Intrauterine growth restriction and prematurity are therefore the principal issues that drive neonatal mortality and morbidity rates in multiple gestations. These data are important for obstetric decision-making and patient counseling.

Section snippets

Material and methods

We performed a retrospective review from the “RDS” database. This data base is a large de-identified collection of neonatal records that is maintained by the Pediatrix Medical Group. This study was approved by the Institutional Review Board of the University of California Irvine. This database includes neonatal records from 124 NICUs that are dispersed geographically throughout the United States. The data are generated from progress notes and discharge summaries that are entered by the

Results

There were 121,774 perinatal records in the data set, of which 51,389 records met the inclusion criteria. We excluded 6751 babies who were not born in the study facilities, 62,464 babies who were <23 or >35 weeks of gestation, 206 higher order multiple births, and 935 babies with congenital anomalies or chromosomal defects. Those babies who were included in the study consisted of 36,931 singletons, 12,302 twins, and 2155 triplets. The gestational age distributions for these babies are shown in

Comment

This in-depth analysis, which is of one of the largest accumulations of data on multiple births, allowed the authors to gather a substantial amount of clinically relevant data. It is reassuring for care of these patients that gestational age-specific mortality rates and survival without significant morbidity are similar for singletons, twins, and triplets. Our study that shows similar mortality rates at various gestational ages for singletons versus multiple births is similar to 2 other recent

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The incidence of extrauterine growth retardation (EUGR) varies considerably in different countries due to the distinct definitions and inclusion criteria of individual studies. Most studies included small for gestational age (SGA) very preterm infants (VPIs), resulting in a higher incidence of EUGR. Experts have suggested the accurate definition of “EUGR” in SGA infants is not “true EUGR”. The postnatal growth curve of multiple premature births also differs from that of singletons. As far as we know, there is no study about relationship between singleton-non-SGA preterm infants and EUGR.
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Editors' ChoiceTwins and triplets: The effect of plurality and growth on neonatal outcome compared with singleton infants

Abstract

Objective

Study design

Results

Conclusion

Section snippets

Material and methods

Results

Comment

Obstet Gynecol

Am J Obstet Gynecol

Semin Neonatol

Am J Obstet Gynecol

Obstet Gynecol

BJOG

Am J Obstet Gynecol

Obstet Gynecol

Obstet Gynecol

Obstet Gynecol

Am J Obstet Gynecol

Trends in multiple births

Stat Bull

Editors' Choice
Twins and triplets: The effect of plurality and growth on neonatal outcome compared with singleton infants