Objective: Offspring of mothers with diabetes have increased birth weight and higher rates of obesity in early childhood. The relative role of maternal glycemia and maternal obesity is uncertain. We therefore studied the impact of maternal glycemia and maternal obesity on offspring birth measures and early postnatal growth in nondiabetic pregnancies.
Research design and methods: We studied 547 full-term singleton babies of nondiabetic parents. Data available included parental height and weight; maternal prepregnant weight; maternal fasting plasma glucose (FPG) at 28 weeks of gestation; and offspring weight and length at birth, 12 weeks of age, and 1 and 2 years of age. Relationships between parental and offspring measures were estimated using Pearson correlations.
Results: Maternal FPG was correlated with offspring birth weight (r = 0.25, P < 0.001), length (r = 0.17, P < 0.001), and BMI (r = 0.2, P < 0.001) but was not correlated with offspring growth at 12 weeks. Maternal prepregnancy BMI was significantly correlated with offspring weight (r = 0.26, P < 0.001), length (r = 0.12, P = 0.01), and BMI at birth (r = 0.26, P < 0.001) and remained correlated with offspring weight (r = 0.13-0.14, P = 0.007-0.002) and BMI (r = 0.14-0.19, P = 0.002 to <0.001) during the first 2 years. Paternal BMI was correlated with offspring weight from 12 weeks onwards (r = 0.11-0.22, P = 0.017 to <0.001), length (r = 0.10-0.12, P = 0.01-0.05), and BMI from 1 year onwards (r = 0.16-0.25, P = <0.001).
Conclusions: In a nondiabetic cohort, the effect of maternal glycemia on birth weight is transitory, while the impact on growth of maternal BMI continues into early childhood. The independent association of paternal BMI with offspring postnatal growth suggests that the impact of parental BMI could be explained by genetic factors, shared environment, or both.