Pregnancy Weight Gain
IOM Guideline Tracker
Track healthy pregnancy weight gain based on pre-pregnancy BMI using the IOM guidelines.
Pregnancy Weight Gain Calculator
Track healthy weight gain during pregnancy based on IOM guidelines.
IOM Pregnancy Weight Gain Guidelines
The Institute of Medicine released updated pregnancy weight gain guidelines in 2009 after reviewing outcomes from thousands of pregnancies. They're based on pre-pregnancy BMI because women entering pregnancy at different sizes have different fat stores available to support fetal growth.
First Trimester Is Flat
Most women gain very little in the first 13 weeks — 1 to 4 pounds is typical, and some lose a little due to nausea. Gain accelerates in the second trimester and stays steady through the third. Rapid early gain isn't dangerous, but it's worth discussing with your OB.
Quality Over Quantity
Weight gain is a rough proxy for nutrition. A woman hitting her numbers on ultra-processed foods is not in the same nutritional position as one eating whole foods. Prenatal vitamins, adequate protein (about 1.1 g/kg), iron, folate, choline, and omega-3s matter more than the scale.
Singleton Pregnancy
Medical Disclaimer
Every pregnancy is different. Work with your obstetrician or midwife for personalized recommendations, especially if you have gestational diabetes, hypertension, a history of pregnancy complications, or are carrying multiples.