Preparing for Baby: Watch Your Weight

By Editorial Staff

Weight gain is inevitable during pregnancy. If nothing else, a woman gains the weight of her developing child, plus additional weight (placenta, uterus, fluid retention). But generally, a woman who is "average" weight prior to conceiving will gain anywhere from 25-35 total pounds over the course of nine months. That's healthy and normal; it's the weight a woman carries before becoming pregnant that can cause problems.

In this case, we're talking about a child's risk of developing asthma, and research involving nearly 250,000 infants suggests a woman's pre-pregnancy weight can play a role. Specifically, compared with normal body-mass index, maternal obesity increased the risk that a woman's child would develop asthma.

Interestingly, being underweight prior to becoming pregnant  also had health consequences for the child; while below-normal BMI didn't raise asthma risk, it did increase the risk the child would develop dermatitis.

Weight gain during pregnancy wasn't a factor, by the way; according to the study, published in Paediatric and Perinatal Epidemiology, no association was noted between maternal gestational weight gain and allergic disease development among offspring. However, pre-pregnancy weight above normal BMI and gestational weight gain above recommended guidelines were both "highly prevalent" in the study.