Maternal obesity and the fetal brain
By Andrea G Edlow MD MSc, Larissa H Mattei BA
May 26, 2016
Contemporary OB/Gyn
... every increase of 1 unit in maternal prepregnancy BMI found to be associated with a significant reduction in offspring IQ and non-verbal IQ, suggesting a dose-response relationship.
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Of note, extremely low maternal pre-pregnancy BMI (<18.5 kg/m2) has also been significantly associated with lower offspring IQ, although the reported decrement is less than in the setting of maternal obesity
While correlation does not mean causation, this article suggests that maintaining a healthy weight prior to pregnancy may provide lasting benefits to the child... including possible influence upon the child's IQ.