Gaining too much or too little weight during pregnancy can risk both mom and baby’s health.
Most women think of pregnancy as the one time in their lives that they are free to gain weight. They carry out nightly refrigerator raids, forgo their formerly tough workout sessions and declare family-size ice cream tubs as single-serving containers. Hey, I do have a family member growing inside of me!
And while anyone who does comment on a pregnant woman’s weight gain will likely live to regret it, there is reason for concern over too-big belly bumps. About half of women gain too much weight during pregnancy, according to a 2015 Obstetrics & Gynecology study of more than 44,000 women. The effects hit more than vanity. Excess weight gain puts women at risk for health problems including pre-eclampsia (a potentially deadly condition marked by high blood pressure and damage to organs such as the kidneys), says Gema Sanabria-Martinez, a maternal and fetal medicine researcher at the Virgen de la Luz Hospital in Spain.
Furthermore, excess weight gain is to blame for up to 20 percent of pregnant women developing gestational diabetes, in which blood sugar levels are too high during pregnancy. Women who develop gestational diabetes are seven times more likely to develop Type 2 diabetes in the years following pregnancy. This may be due to metabolism disorders that can progress during gestational diabetes, Sanabria-Martinez says.
Mom’s weight can also affect baby’s health. After delivery, babies born to mothers with gestational diabetes are at risk for hypoglycemia (low blood sugar), jaundice, breathing problems and admittance to the neonatal intensive care unit, adds Stephen Thung, chief of obstetrics at The Ohio State University Wexner Medical Center. Children of women who gain too much weight during pregnancy are also more than four times likelier to be overweight at age 3 than those whose mothers gained the right amount, per research from Harvard Medical School.
While less common than gaining too much weight, gaining too little (or even losing) weight during pregnancy can also contribute to serious health complications, including preterm births, low birth weights and, according to a 2014 American Journal of Obstetrics and Gynecology study, overweight children. In the recent Obstetrics & Gynecology study, about 1 in 5 women didn’t gain enough weight during pregnancy. Women with the highest BMIs or body mass indexes, indicators of one’s height-to-weight ratio, were twice as likely to gain too little weight compared to other women in the study.
Know Your Numbers: Healthy Weight Gain During Pregnancy
So where’s the scale-moving sweet spot? Well, it depends on how much you weighed before your pregnancy test displayed a smiley face. According to the Institute of Medicine’s current guidelines, women who were at a normal weight (a BMI of 18.5 to 24.9) before conception should gain between 25 and 35 pounds during pregnancy. Women who were underweight (a BMI of less than 18.5) should gain between 28 and 40 pounds during pregnancy. Women who were overweight (a BMI of 25 to 29.9), should aim for 15 to 25 pounds. For obese women (a BMI of 30 or greater), 11 to 20 pounds gained is recommended. (Although some experts believe it’s OK for obese women to gain less weight, weight loss during pregnancy is always discouraged, Thung says.)
Therefore, identifying your pre-pregnancy BMI is the best way to determine how the scale should fluctuate during the next nine months. Then, while we know the last thing you want to do when you’re pregnant is step on the scale, weigh in and track your weight every week to make sure you are on track to gain the right amount. Although every woman’s pregnancy weight gain will be different, for a good rule of thumb, normal-weight women should aim to gain a few pounds in the first trimester and 0.8 to 1 pound a week during their second and third trimesters, according to the Institute of Medicine. You’ll want to gain slightly more or less per trimester if you are underweight or overweight heading into pregnancy. Your doctor can help you identify your exact weight-gain goals and keep you on target.
Gain the Right Way
Most women need to rethink the whole “eating for two” mentality. Instead of being an excuse to eat seconds, it should be a reminder that whatever you eat, your baby eats. After all, 2013 research published The FASEB Journal suggests that babies whose mothers eat junk food while pregnant are at increased risk of growing up addicted to junk food.
Thung recommends filling 50 percent of your plate with vegetables, 25 percent with starches like whole grains and 25 percent with lean protein like chicken. Fish is also a great lean, nutrient-rich source of protein. The American Congress of Obstetricians and Gynecologists recommends that pregnant women eat at least two 8- to 12- ounce servings of fish or shellfish per week. Opt for low-mercury choices such as shrimp, salmon and catfish, while avoiding shark, swordfish, king mackerel and tilefish, and limiting white tuna intake to 6 ounces per week.
Avoid excess sugars (including those from sugary, low-fiber fruit juices), and remember that the average woman only needs to consume an extra 200 to 300 calories per day during pregnancy to gain the right amount of weight, Thung says. That amounts to eating an extra apple a day with peanut butter.
Staying active is also important to preventing excessive weight gain, especially if you are having trouble following those nutritional guidelines. In fact, in Sanabria-Martinez’s recent study published in BJOG: an International Journal of Obstetrics and Gynecology, she found that women who exercise during pregnancy are 36 percent less likely to develop gestational diabetes. The American College of Obstetricians and Gynecologists recommends that pregnant women perform moderate-intensity physical activity for a minimum of 30 minutes on most (if not all) days of the week.
And although walking and yoga are great prenatal exercises and should be integrated into any pregnancy exercise routine, if your workouts were much more intense before becoming pregnant, you don’t necessarily need to limit yourself to stereotypical “pregnancy” workouts.
“Women usually reduce physical activity during pregnancy because they believe that physical exercise could produce disorders such as miscarriages, preterm deliveries or small babies,” says Sanabria-Martinez. Or they just don’t feel like exercising. However, unless your doctor advises otherwise (make sure to discuss exercise with your OB-GYN before breaking a sweat during pregnancy), you should be able to continue your pre-pregnancy workouts throughout pregnancy. Bonus: Hitting the gym while pregnant can help improve your energy levels, help you sleep better and reduce back pain. Win-win.
Written for Health.USnews.com