The risk of being hospitalised during pregnancy is fourfold if overweight, writes Kathryn Holmquist

Want to have a baby? Lose weight first. Women who are overweight or obese are up to 40 per cent more likely to have a baby with a major birth defect than women of normal weight.

This is according to a report by the March of Dimes Task Force on Nutrition and Optimal Human Development in the US.

"It's an area where weight matters more than we think," says Dr Richard Deckelbaum, chairman of the task force and director of the Institute of Human Nutrition at Columbia University in New York City.

It is more difficult for women to get pregnant when they are overweight and, if pregnancy does occur, the risk of complications during pregnancy and problems for the baby after birth increase dramatically.

Overweight and obese women are also at increased risk of having complications during pregnancy, according to the report.

The risk to a woman of being hospitalised during pregnancy is fourfold if she is overweight.

Deckelbaum believes that the public have got the message about some of the things important to a healthy pregnancy and baby, such as folic acid supplementation, but that the message about being in shape before pregnancy has been lost.