Macrosomic Newborns Delivered at Term after Labor among Nondiabetic Women: Maternal and Neonatal Morbidities

Abstract

Abstract Objective This study aimed to compare morbidities among nonmacrosomic versus macrosomic singleton live births of nondiabetic women who labored. Study Design This retrospective study utilized the 2003 revision of U.S. birth certificate data of singleton live births (2011–2013) at 37 to 41 weeks who labored. The primary outcomes were composite maternal and neonatal morbidities (CMM and CNM, respectively). We compared these outcomes by birth weight, 2,500 to 3,999 g (group 1; reference), 4,000 to 4,449 g (group 2), and 4,500 to 5,999 g (group 3). We used multivariable Poisson regression analyses to examine the association between birth weight groups and the outcomes. Results Among 6,691,338 live births, 92.0% were in group 1, 7.1% in group 2, and 0.9% in group 3. The overall CMM and CNM rates were 4.4 and 6.8 per 1,000 live births, respectively. Compared with group 1, the risk of CMM was significantly higher in group 2 (adjusted risk ratio [aRR] = 1.50; 95% confidence interval [CI]: 1.44–1.56) and group 3 (aRR = 2.00; 95% CI: 1.82–2.19). Likewise, the risk of CNM was significantly higher in group 2 (aRR = 1.38; 95% CI: 1.33–1.43) and group 3 (aRR = 2.57; 95% CI: 2.40–2.75) than in group 1. Conclusion Nondiabetic women who labor with a macrosomic newborns have a significantly higher rate of adverse outcomes than nonmacrosomic.