Weight retention from early pregnancy to three years postpartum: a study in Iranian women

Objectivesto examine weight retention from early pregnancy to three years postpartum in Iranian women.Designa prospective cohort study.Setting12 health centres selected at random in urban and rural areas in Guilan.Participants1315 pregnant women (705 in urban areas and 610 in rural areas) who regularly attended health centres for antenatal care and growth monitoring of their babies.Measurementsdetails of weight, height, pregnancy weight gain, body weight at one to three years postpartum, mother's age, parity, duration of any breast feeding, education and employment status of women who carried singleton fetuses and delivered at term were collected at the first antenatal visit. The women were categorised based on their pre-pregnancy body mass index, weight retention at one to three years postpartum, employment status and educational levels.Findingswomen who gained more weight than recommended during pregnancy tended to be heavier at three years postpartum than women who gained weight within the recommended ranges during pregnancy (7.0±5.3 versus 4.8±6.7 kg; p<0.0001). Less-educated women were at greater risk for inadequate pregnancy weight gain than other educational groups, and they had less weight retention at three years postpartum than other educational groups. Also, weight retention for primiparous women was higher than that for multiparous women (5.4±6.6 versus 3.8±6.3 kg; p<0.0001). The results of logistic regression analysis revealed that only total pregnancy weight gain was independently related to major weight retention (⩾4 kg) at three years postpartum (odds ratio 1.34, 95% confidence intervals 1.03–1.74; p=0.02).Conclusiona high body mass index before pregnancy is not associated with increased risk of retaining more weight after pregnancy. On the other hand, total pregnancy weight gain was the most important determinant of weight retention at three years postpartum in this population of Iranian women.