Maternal obesity, gestational diabetes, and central nervous system birth defects.

Abstract

BACKGROUND:

Maternal obesity and diabetes are both associated with increased risk of congenital central nervous system (CNS) malformations in the offspring and may share a common underlying mechanism. Our objective was to evaluate whether gestational diabetes influenced the association of prepregnancy maternal obesity and risks for CNS birth defects.

METHODS:

This Texas population-based case-control study evaluated births occurring January 1997 through June 2001. Data came from structured telephone interviews. Cases (n=477) were mothers of offspring with anencephaly (n=120), spina bifida (n=184), holoprosencephaly (n=49), or isolated hydrocephaly (n=124). Controls (n=497) were mothers of live infants without abnormalities randomly selected from the same hospitals as cases. Response rates were approximately 60% for both cases and controls. We evaluated maternal obesity (body mass index > or =30.0 kg/m) and risks for CNS birth defects, as well as whether gestational diabetes influenced the risks.

RESULTS:

After adjusting for maternal ethnicity, age, education, smoking, alcohol use, and periconceptional vitamin use, obese women had substantially increased risks of delivering offspring with anencephaly (odds ratio=2.3; 95% confidence interval=1.2-4.3), spina bifida (2.8; 1.7-4.5), or isolated hydrocephaly (2.7; 1.5-5.0), but not holoprosencephaly (1.4; 0.5-3.8). Odds ratios were higher for the joint effects of maternal obesity and gestational diabetes, with evidence for interaction on a multiplicative scale.

CONCLUSIONS:

Maternal obesity and gestational diabetes may increase the risk of CNS birth defects through shared causal mechanisms.

• Authors: James L Anderson, D Kim Waller, Mark A Canfield, Gary M Shaw, Margaret L Watkins, Martha M Werler
• Journal: Epidemiology (Cambridge, Mass.) (Epidemiology) Vol. 16 Issue 1 Pg. 87-92 (Jan 2005) ISSN: 1044-3983 [Print] United States
• PMID: 15613950 (Publication Type: Journal Article, Research Support, U.S. Gov't, P.H.S.)

Topics

• Central Nervous System Diseases (etiology)
• Congenital Abnormalities (etiology)
• Diabetes, Gestational (complications)
• Educational Status
• Female
• Humans
• Maternal Age
• Obesity (complications, ethnology)
• Pregnancy
• Risk Factors
• Texas (epidemiology)