Patterns of gestational weight gain among overweight and obese women related to small- and large-for-gestational-age births

OBJECTIVE: Maternal obesity is associated with increased risk of large-for-gestational-age (LGA) and small-for-gestational-age (SGA) births. Both are related to childhood obesity. We considered that patterns of gestational weight gain (GWG) may help to disentangle these competing risks. DESIGN AND METHODS: Patterns of GWG were characterized among a cohort of overweight or obese women (n=651). Polytomous logistic regression models tested for associations between GWG patterns and birthweight outcomes: SGA (<10(th)) and LGA (>90(th) percentile). RESULTS: Rates of SGA were higher than those for LGA (14.9% vs. 7.8%). Four GWG patterns were identified: consistently high (29%), early adequate/late high (33%), consistently adequate (18%), and consistently low (20%). Risk of LGA was highest in women with consistently high GWG (adjusted odds ratio [OR] 4.62 [1.53, 13.96]), and risk was elevated, but with lower magnitude, among women with early adequate/late high gains (OR 3.07 [1.01, 9.37]). High GWG before 20 weeks, regardless of later gain, was related to LGA. Low gain before 20 weeks accompanied by high gain later may be associated with reduced SGA risk (0.55 [0.29, 1.07]). CONCLUSIONS: The pattern of weight gain during pregnancy may be an important contributor to or marker of abnormal fetal growth among overweight and obese women.