You just found out you’re going to be a mom. Congratulations! While you’re painting the nursery, buying tiny onesies, and picking potential names, there’s something else to consider: gaining a healthy amount of baby weight! According to the Los Angeles Times, women who start their pregnancy at a normal weight are advised to gain between 25 and 35 pounds and overweight women are told to gain 15 to 25 pounds. However, statistics show that over half of the women of childbearing age are already overweight and a third of pregnant women gain more than doctors recommend. All that excess weight raises the risk of gestational diabetes, high blood pressure, C-sections, delivery complications, and birth defects. Studies also show that babies born to overweight women are more likely to become overweight adults.

On the flip side, gaining too little weight during pregnancy is dangerous. It’s even got a name: Pregorexia! That’s when a mother-to-be is so obsessed with not getting fat during pregnancy, she diets and exercises like crazy, and puts her baby’s health at risk. Part of the reason for the rise in pregorexia is celebrities like Nicole Kidman and Nicole Richie.These are women in the spotlight who stayed slim during pregnancy, with barely detectable baby bumps, and looked thin again immediately after giving birth.

Not gaining enough weight leads to poor fetal growth, lower birth weight, and an increased chance of a premature birth. Too much exercise can also hurt. Sensible exercise during pregnancy leads to better physical and mental health for mothers, better deliveries, better postpartum recoveries, and even a higher IQ for the baby. However, if you exercise to the point of exhaustion, it deprives the fetus of oxygen, which has been linked to neurological defects. So, talk to your doctor about the right amount of exercise for you. You should get a minimum of 30 minutes of moderate cardiovascular activity 4 days a week. That means walking briskly, dancing, or swimming. If you'd like to go further, check out the book: the Mayo Clinic Guide to a Healthy Pregnancy.