Maternal Body Mass Index during Pregnancy and Offspring Neurocognitive Development

This hypothesis generating study explores second trimester maternal body mass index (BMI) during pregnancy and offspring neurocognitive development.

Mothers and offspring served as controls in two earlier studies: 101 children at age two years and 118 children at age eight years.

Frequency of maternal BMI ≥30 kg/m² increased from 10% in 1987-1990 to 30% in 2004-2006 (P < 0.001); the socioeconomic gradient became more pronounced. At age two, one or more BSID-III (Bayley Scales of Infant Development, 3rd Edition) scores <85 were more frequent with higher maternal BMI (P = 0.029); regression analysis suggested an inverse relationship between language scores and BMI (P = 0.054). Among eight-year-olds, one or more WISC-III (Wechsler Intelligence Scale for Children, 3rd edition) scores <85 increased with maternal BMI (P = 0.017); regression analysis showed an inverse relationship between performance subscale IQ score and BMI (P = 0.023).

Second trimester maternal obesity may be an independent risk factor for some aspects of children's neurocognitive development. Further study is indicated.