Pregnancy: is obesity a teratogen?

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  • Obesity during early pregnancy associated with an increased risk for major congenital malformations.

Why this matters

  • Consider preconception counseling in overweight women.
  • Hyperglycemia is associated with increased oxidative stress and the production of free radical species.

Key results

  • Major congenital malformations: 3.4% in underweight, 3.4% for normal weight, 4.2% in class II obesity, 4.7% in class III obesity.
  • Adjusted risk ratios (aRR) for congenital malformation increased with maternal BMI compared with normal weight women (overweight: aRR, 1.05 [95% CI, 1.02-1.07], obesity class I: aRR, 1.12 [95% CI, 1.08-1.15], obesity class II: aRR, 1.23 [95% CI, 1.17-1.30], obesity class III: aRR, 1.37 [95% CI, 1.26-1.49]).
  • Congenital heart defects were most prevalent.

Study design

  • Cohort obtained from the Swedish medical birth register.
  • ...