Gestational weight gain among average-weight and overweight women--what is excessive?

Our purpose was to determine the association between increased gestational weight gain and birth weight outcomes for low-income women.

A total of 53,541 single, live infants delivered from 1990 to 1991 to white, black, and Hispanic women in eight states were evaluated. Multiple logistic regression was used to calculate risk of low and high (> 4500 gm) birth weight, adjusting for selected factors.

The association between gestational weight gain and birth weight varied by prepregnancy body mass index. Risk for low birth weight decreased with increasing weight gain for average-weight women. There was no reduction in risk for low birth weight, however, beyond weight gains of 30 to 34 pounds for overweight women and 15 to 19 pounds for very-overweight women. Risk for high birth weight, however, increased with increasing weight gain in all three groups.

Very-overweight women (body mass index > 29 kg/m2) may benefit from an upper guideline of 25 pounds of weight gain to help reduce risk for high birth weight.