ABSTRACT
Background: Maternal prepregnancy adiposity may influence child
adiposity beyond the transmitted genetic effects, which, if true, may
accelerate the obesity epidemic, but the evidence for this mechanism
is inconsistent.
Objective: The aim was to assess whether the associations of maternal
body mass index (BMI) with child anthropometric measurements from birth
through infancy and at 7 y of age exceed those of paternal associations.
Design: In the Danish National Birth Cohort, information on parental
and child anthropometric measures is available for 30,655 trio
families from maternal interviews during pregnancy and the postpartum
period and from a 7-y follow-up. By using multiple linear
and logistic regression models of child SD (z) scores of weight and
BMI at birth, 5 mo, 12 mo, and 7 y of age, and of child overweight at
age 7 y, we compared associations with maternal prepregnancy and
postpartum BMI z scores and with paternal BMI z scores.
Results: When comparing maternal-child and paternal-child BMI z
score associations, the strongest associations were observed with
mothers’ BMI at birth [maternal and paternal BMI z scores: 0.143
(95% CI: 0.130, 0.155) and 0.017 (95% CI: 0.005, 0.029), respectively]
and throughout infancy, but the relative difference in the associations
declined by child age [for BMI z score at child age 7 y per maternal
and paternal BMI z scores: 0.208 (95% CI: 0.196, 0.220) and 0.154
(95% CI: 0.143, 0.166), respectively]. At 7 y of age, ORs of child
overweight were 2.30 (95% CI: 1.99, 2.67) by maternal overweight
and 1.96 (95% CI: 1.74, 2.21) by paternal overweight. There were no
differences between the results based on maternal BMI before and
after pregnancy or on child’s weight adjusted for length or height.
Conclusions: The associations of child weight and BMI with maternal
BMI were stronger than with paternal BMI. The differences
between the associations were strong at birth but declined with child
aging.