Details

Autor(en) / Beteiligte

• Bruckner, Tim A., PhD, MPH
• Mayo, Jonathan A., MPH
• Gould, Jeffrey B., MD
• Stevenson, David K., MD
• Lewis, David B., PhD
• Shaw, Gary M., DrPH
• Carmichael, Suzan L., PhD

Titel

Heightened risk of preterm birth and growth restriction after a first-born son

Ist Teil von

• Annals of epidemiology, 2015-10, Vol.25 (10), p.743-747.e1

Ort / Verlag

United States: Elsevier Inc

Erscheinungsjahr

2015

Link zum Volltext

Quelle

MEDLINE

Beschreibungen/Notizen

• Abstract Purpose In Scandinavia, delivery of a first-born son elevates the risk of preterm delivery and intrauterine growth restriction of the next-born infant. External validity of these results remains unclear. We test this hypothesis for preterm delivery and growth restriction using the linked California birth cohort file. We examined the hypothesis separately by race and/or ethnicity. Methods We retrieved data on 2,852,976 births to 1,426,488 mothers with at least two live births. Our within-mother tests applied Cox proportional hazards (preterm delivery, defined as less than 37 weeks gestation) and linear regression models (birth weight for gestational age percentiles). Results For non-Hispanic whites, Hispanics, Asians, and American Indian and/or Alaska Natives, analyses indicate heightened risk of preterm delivery and growth restriction after a first-born male. The race-specific hazard ratios for preterm delivery range from 1.07 to 1.18. Regression coefficients for birth weight for gestational age percentile range from −0.73 to −1.49. The 95% confidence intervals for all these estimates do not contain the null. By contrast, we could not reject the null for non-Hispanic black mothers. Conclusions Whereas California findings generally support those from Scandinavia, the null results among non-Hispanic black mothers suggest that we do not detect adverse outcomes after a first-born male in all racial and/or ethnic groups.