Gestational weight gain by body mass index among US women delivering live births, 2004-2005: fueling future obesity

Objective Current pregnancy weight gain guidelines are based on prepregnancy body mass indices (BMI), but gestational weight gains by BMI class among US women are unknown. Study Design We assessed the amount of gestational weight gain among 52,988 underweight, normal-weight, overweight, and obese US women who delivered a singleton, full-term infant in 2004-2005. Excessive weight gain during pregnancy was defined as gaining 35 or more pounds for normal-weight and 25 or more pounds for overweight women. Results Approximately 40% of normal-weight and 60% of overweight women gained excessive weight during pregnancy. Obese women gained the least, although one-fourth of these women gained 35 or more pounds. Excessive weight gain levels were highest among women aged 19-years-old or younger and those having their first birth. Conclusion Excessive gestational weight gains were common, especially among the youngest and those who were nulliparous. These results predict higher obesity levels from pregnancy weight gains among US women.