The 130th Annual Meeting of APHA

4050.0: Tuesday, November 12, 2002 - 8:30 AM

Abstract #50147

Perinatal mortality in first-born versus second-born twins: Effects of birthweight and fetal growth restriction

Wendy C. Sheay, MPH, School of Public Health, University of Medicine and Dentistry of NJ, 170 Frelinghuysen Road, Piscataway, NJ 08854, 732-445-0199, sheaywe@umdnj.edu and Cande V. Ananth, PhD, MPH, Department of Obstetrics, Gynecology, and Reproductive Sciences/Division of Epidemiology and Biostatistics, University of Medicine and Dentistry of NJ/Robert Wood Johnson Medical School, 125 Paterson Street, New Brunswick, NJ 08901.

The rate of twinning in the US has increased dramatically in the past 25 years. Twins suffer higher perinatal mortality rates (PMR: fetal deaths at less than 20 weeks plus deaths within 28 days after birth) than singletons, with the rates of second-born twins exceeding those born first. We evaluated the relationship of birthweight and fetal growth restriction (FGR) with PMR in first- and second-born twins. Analyses were based on the 1995-97 US matched multiple birth/fetal death files assembled by the National Center for Health Statistics. Mortality was 16.8 for first-born twins compared with 20.0/1,000 for second-born twins (relative risk=1.20; 95% confidence interval=1.16, 1.25). Mortality rates of second-born twins surpassed those of first-born twins at every 500-gram birthweight category. We then examined mortality in relation to relative birthweight (z-score); PMR were similar to those of absolute weights. PMR were consistently higher in second-born than first-born twins at each gestational age beyond 26 weeks. FGR, defined as mean birthweight by gestational age, showed a similar pattern between first- and second-born twins. The disparity in mortality rates between first- and second-born twins might be related to pregnancy complications.

Learning Objectives:

Keywords: Perinatal Health, Mortality

Presenting author's disclosure statement:
I do not have any significant financial interest/arrangement or affiliation with any organization/institution whose products or services are being discussed in this session.

Outstanding Student Papers in Maternal and Child Health

The 130th Annual Meeting of APHA