Socioeconomic, demographic and nutritional factors associated with maternal weight gain in general practices in Southern Brazil.

In order to describe adequacy of weight gain during pregnancy and its association with pre-pregnancy nutritional status and other factors, a cohort study of pregnant women enrolled at 16-36 weeks of gestation and followed up until delivery was carried out in prenatal care in primary care services in Rio Grande do Sul State, Brazil. Maternal weight was recorded at each prenatal care visit. Weight gain was classified as "adequate," "insufficient" or "excessive" (Institute of Medicine). Poisson regression was used to measure the associations. The sample was comprised of 667 women, and insufficient and excessive weight gain incidences were 25.8% and 44.8%, respectively. Overweight and obese before pregnancy had a significant increased risk of excessive weight gain in pregnancy (RR: 1.75; 95%CI: 1.48-2.07, RR: 1.55; 95%CI: 1.23-1.96, respectively). Women with fewer than six prenatal visits had a 52% increased risk for weight gain below recommended values. Although insufficient weight gain may still be a public health problem, excessive gain is becoming a concern that needs immediate attention in prenatal care.