One of the most challenging yet common conversations I have with pregnant patients concerns weight gain. Though most women logically know better, many pregnant women have a hard time giving up that old idea that they are “eating for two.”

According to the Institute of Medicine, most women should only be gaining 25 to 35 lbs. during their entire pregnancy. These guidelines apply to women with a healthy weight for height (body mass index, 18.5–24.9).

Women who are overweight (BMI 25–29.9) should limit pregnancy weight gain to 15 to 25 lbs., and obese women (BMI 30 or greater) should only gain between 11 and 20 lbs.  

Increased weight gain in pregnancy can increase the risk for gestational diabetes, preeclampsia and large for gestational age babies, as well as childhood obesity in offspring. Women who gain excess weight in pregnancy also have a higher chance of cesarean birth.

Extra weight during pregnancy can make losing the weight during the postpartum period more difficult, and makes it more challenging to maintain a healthy weight in subsequent pregnancies, particularly if pregnancies are closely spaced.

Despite the risks, this topic remains difficult to broach with my patients. Many women find that eating frequently is the only way to fight nausea in the early months of gestation. Others feel that pregnancy is a free pass to consume anything and everything want, and many women experience frequent, strong cravings for unhealthy foods.

In reality, most pregnant moms only need to consume an extra 300 calories a day. I try to discuss diet at every prenatal visit, and will often ask my patients to keep a food diary for a few days, so we can discuss their choices at the next visit.

I discourage pregnant women from eating empty calories, like soda and candy, and encourage small, frequent protein-rich meals instead of three large meals a day.

I also encourage daily moderate exercise such as walking, swimming or yoga to help maintain a healthy weight during pregnancy.

Robyn Carlisle, MSN, CNM, WHNP, works as a full-scope midwife at University Doctors and Kennedy University Hospital in Sewell, N.J.