Risk of major birth defects rises with severity of mother’s overweight

The risk of major congenital malformations during the first year of life increases with a mother’s weight, from 5% higher in women who are overweight to 37% higher in women with the most severe obesity, a large cohort study in The BMJ has found.1

The findings prompted researchers to advise doctors to encourage women who are planning to become pregnant to establish a normal weight before conceiving.

Maternal obesity is already known to increase the risk of congenital malformations, but it was not clear whether overweight mothers all carry similar risks or whether these risks increase with …