Doctors base how much weight a woman should gain when she's pregnant on how much she weighed at the start. That means 25 to 35 pounds for a woman of normal weight, 15 to 25 for overweight women and less than 20 pounds for obese women.
In a study by researchers at Penn State College of Medicine, all of the overweight women exceeded the recommended weight gain, and nine of the obese did. Most said they didn't receive specific advice on weight gain at the start of pregnancy,
Overweight and obese women already have a higher risk of pregnancy complications.