Alcohol drinking pattern during pregnancy and risk of infant mortality

Abstract

Background: The safety of small amounts of alcohol drinking and occasional binge-level drinking during pregnancy remains unsettled. We examined the association of maternal average alcohol intake and binge drinking (>or=5 drinks per sitting) with infant mortality, both in the neonatal and postneonatal period.

Methods: Participants were 79,216 mothers who were enrolled in the Danish National Birth Cohort in 1996-2002, gave birth to a live-born singleton, and provided information while they were pregnant on alcohol consumption during pregnancy. Information on infant mortality and causes of death was obtained from national registries and medical records.

Results: During the first year of life, 279 children (0.35%) died, 204 during the neonatal period. Infant mortality was not associated with alcohol drinking, even at a consumption level of either 4+ drinks per week or 3+ occasions of binge drinking. Postneonatal mortality was associated with an intake of 4+ drinks per week (hazard ratio = 3.56 [95% confidence interval = 1.15-8.43]) and with 3+ binge episodes (2.69 [1.27-5.69]). When restricting analyses to term births, both infant mortality and postneonatal mortality were associated with a weekly average intake of 4+ drinks or 3+ binge episodes.

Conclusions: Among term infants, intake of at least 4 drinks of alcohol per week or binging on 3 or more occasions during pregnancy are associated with an increased risk of infant mortality, especially during the postneonatal period.