Weight gain between pregnancies can also be a problem. In a study of more than 150,000 Swedish women, Harvard and Swedish researchers found that, even in normal weight women, gaining just seven pounds between pregnancies can up the risk of high blood pressure, and stillbirth. And the chance of diabetes rose 30 percent from that small weight gain. But weight loss between pregnancies has its dangers, too. An Irish study found that women whose BMIs lowered by five or more units raised the risk of premature births.
So, what’s an expectant mom to do? Crites offers her suggestions:
Don’t gain fat.
Pregnancy weight breaks down like this: baby, eight pounds; amniotic fluid, three; placenta, one; extra blood, four; and a few extra for breast tissue and fluids. “That’s not fat,” says Crites. “That’s weight to support the pregnancy.”
Keep on moving.
“Most patients gain too much weight not because they’re not smart and don’t know better but because they reduce their activity,” says Crites. “It’s OK to go to the gym.” Check with your doctor first.
Pace your gain.
Normal and underweight women should gain about two to four pounds a month. “But if you’re overweight,” says Crites, “maintain your weight within five to ten pounds.”