Q: Is weight gain during pregnancy related to premature delivery?

A: Yes, weight gain in the second half of pregnancy is related to the risk of preterm delivery.
You have a higher risk of delivering early:

  • If you are underweight and normal-weight and you gain on average less than 0.8 pounds per week in the second trimester 
  • If you are overweight and obese and you gain on averag less than 0.7 pounds per week in the third trimester

Low rates of weight gain in the first half of pregnancy are more closely related to the birth of small infants, especially among women who begin pregnancy underweight.