It's a tough subject -- weight gain during pregnancy. You have cravings, you feel entitled to indulge a little bit, you need to eat to stave off nausea -- you're eating for two! But how much is too much?

A new study -- conducted on 40,000 women and their babies and published in the November issue of Obstetrics & Gynecology -- found that women who gained more than 40 pounds during their pregnancies were nearly twice as likely to have a heavy baby. What's a heavy baby? A nine-pounder or more. And heavy babies are more likely to become overweight or obese later in life.

According to the study, more than one in five women gains excessive weight -- deemed as more than 40 pounds.

The study found that women who gain too much are even more likely to have heavy babies than women who have gestational diabetes.

So how to maintain a little balance? There are some good ideas -- and support from women with the same goals -- in the Staying Fit During Pregnancy group.

And here are some no-nonsense tips from the lead author of the weight gain study, Dr. Teresa Hillier, MD, an endocrinologist and senior investigator at the Kaiser Permanente Center for Health Research in Oregon and Hawaii:

Tips for Healthy Weight Gain During Pregnancy

  • Eat foods loaded with nutrients for your baby: fruits, vegetables, low-fat dairy, and protein.
  • Avoid high-fat, high-carb, and calorie-dense foods and drinks such as processed foods, soda, and fried foods.
  • Listen to your internal hunger signals, eat frequent small meals when hungry, and stop when full.
  • Exercise every day (check with your doctor first.)
  • Join a prenatal exercise class to connect with other pregnant women and learn about activity geared to pregnancy.

What about you? How much weight have you gained, and are you worried about gaining too much?