What is the Right Amount of Weight to Gain During Pregnancy?

Eat this; don’t eat that. Stay active, just don’t push yourself too hard. Don’t stress about the weight gain — but don’t gain too much weight, either. 

If you’re expecting a baby, chances are you’ve been inundated with all sorts of advice from well-meaning family, friends, and even perfect strangers about what you should and shouldn’t do to ensure a healthy pregnancy.   

While you’re sure to receive valuable tips and suggestions on how to sleep more comfortably, soothe persistent heartburn, and avoid stretch marks, specific advice about weight gain should be taken with a proverbial grain of salt.  

That’s because there’s no single “right” amount of weight gain for all pregnant women; there’s just the right amount based on your specific, individual needs. Here’s what you should know. 

Pregnancy weight gain basics

While your growing baby is responsible for some of the weight you gain during pregnancy, your body also stores extra calories to fuel your baby’s rapid growth through the third trimester and help you produce enough breast milk to nourish your baby once they’re born. 

Gaining the “right” amount of weight during pregnancy means gaining just what you need — not less or more than you need — to nourish your growing baby. 

Gaining too little weight can compromise your baby’s growth and development, putting them at an increased risk of being born with health problems, at a low birth weight, or both. 

Besides boosting your chances of developing serious pregnancy complications like gestational diabetes and preeclampsia, gaining too much weight can lead to increased birth weight and long-term postpartum weight retention. 

Gaining weight at a steady rate that falls within the recommended boundaries, on the other hand, can help you avoid common pregnancy pitfalls like varicose veins, stretch marks, hemorrhoids, and backaches; it also makes you less likely to experience severe pregnancy-induced fatigue.  

Total weight gain guidelines

You’ve probably heard that most pregnant women should gain a total of 25 to 35 pounds, but don’t let that generalization lead you astray. In reality, there’s no one-size-fits-all approach to pregnancy weight gain. 

The amount of added weight that’s best for you is determined by your pre-pregnancy weight and body mass index (BMI), and whether you’re carrying one baby, twins, or multiples. 

Your BMI, or the standard measure of body fat calculated from your weight and height, helps establish whether you’re underweight, at a normal weight, overweight, or obese. This online calculator can help you figure out which BMI category you fall into: 

• Underweight = less than 18.5 BMI
• Normal weight = 18.5 to 24.9 BMI
• Overweight = 25 to 29.9 BMI 
• Obese = 30 or higher BMI

Once you know your pre-pregnancy BMI category, you can work out how much weight you should gain based on the current Institute of Medicine guidelines, which state that:  

• Underweight women should gain 28 to 40 pounds
• Normal-weight women should gain 25 to 30 pounds
• Overweight women should gain 15 to 25 pounds
• Obese women (all categories) should gain 11 to 20 pounds

If you’re carrying twins or multiples, you’ll need to gain even more weight to support a healthy pregnancy; an underweight woman who’s carrying twins should aim to gain a total of 50 to 62 pounds during her pregnancy. 

Weight gain by trimester

The rate at which you gain weight during pregnancy is just as important as the total amount of weight you gain. If you’re at a normal, healthy body weight before pregnancy, you can expect to gain about two to four pounds during your first trimester, and about one pound per week for the rest of your pregnancy. 

Steady weight gain is just as important if you’re underweight, overweight, or obese when you become pregnant, but the amount of weight you should gain in each trimester (and week by week) is determined by your specific needs.

Healthy, controlled weight gain

Here at Serrano OBGyn, we believe that helping expectant moms manage their weight gain is an essential part of quality prenatal care. 

Besides helping you understand what kind of food you should choose and how many calories you should consume when you’re “eating for two,” we provide detailed advice on how to stay fit and active through your pregnancy. 

Above all, we’re here to offer guidance and support to ensure your pregnancy is healthy and enjoyable. Call our San Antonio, Texas, office today, or click online to schedule an appointment with board-certified obstetrician Dr. Christopher Serrano any time.