The impact of maternal flood-related stress and social support on offspring weight in early childhood

The current study examined the moderating role of social support in the association between prenatal maternal stress (PNMS) and childhood body mass index (BMI) in the context of the Iowa floods of 2008. In addition, the mediating role of offspring birthweight was examined in the association between PNMS and childhood BMI. We recruited women from eastern Iowa who were pregnant in 2008 when disastrous floods occurred. Self-report measures of PNMS and cognitive appraisal of the flood's consequences were obtained shortly after the disaster. Social support was assessed during pregnancy. Offspring anthropometric measures were collected at birth and 30 months. Moderated mediation results indicated that greater PNMS predicted greater BMI at age 30 months through effects on higher birthweight as a mediator, but only for participants with low social support. High social support (satisfaction or number) buffered the effect of PNMS or a negative appraisal of the flood on birthweight. The combination of high PNMS or a negative appraisal of the flood's consequences and low social support resulted in higher offspring birthweight, which predicted greater BMI at 30 months. Providing strong social support to pregnant women following a stressor might buffer the effects of PNMS on offspring birthweight and later obesity.