Timing of gestational weight gain in association with birth weight outcomes: a prospective cohort study

Abstract

Maternal gestational weight gain (GWG) is an important determinant of infant birthweight and having adequate total GWG has been widely recommended. However, the association of timing of GWG with birthweight remains controversial. We aimed to evaluate the association of timing of GWG with birthweight, especially among women with adequate total GWG. In a prospective cohort study, pregnant women’s weight was routinely measured during pregnancy, and their GWG was calculated for the 10 intervals: the first 13, 14–18, 19–23, 24–28, 29–30, 31–32, 33–34, 35–36, 37–38, and 39–40 weeks. Birthweight was measured and small- and large-for-gestational-age were assessed. Generalized linear models with Gaussian distribution and Poisson models were used to evaluate the associations of GWG with birthweight and birthweight outcomes after multivariate adjustment, respectively. Of the 5049 women, increased GWG in the first 30 weeks was associated with increased birthweight for male infants (birthweight increased by 63.91 (95% CI 28.64, 99.19), 105.07 (77.54, 132.61), 95.10 (65.18, 125.02), 70.31 (40.24, 100.39), and 73.59 (46.09, 101.08) g for 0.5 kg/wk increase in GWG during the first 5 intervals, respectively), and increased GWG in the first 28 weeks was associated with increased birthweight for females (birthweight increased by 47.99 (95% CI 9.85, 86.13), 81.12 (52.15, 110.08), 75.46 (46.52, 104.40), and 61.06 (32.18, 89.94) g for 0.5 kg/wk increase in GWG during the first 4 intervals, respectively). Among 1713 women with adequate total GWG, increased GWG percent between 14–23 weeks was associated with increased birthweight. Moreover, inadequate GWG between 14–23 weeks, compared with the adequate GWG, was associated with an increased risk of small-for-gestational-age (43 [13.7%] vs 42 [7.2%]; relative risk 1.83, 95% CI 1.21, 2.76). Timing of GWG may influence infant birthweight differentially, and women with inadequate GWG between 14–23 weeks may be at higher risk of delivering small-for-gestational-age infants, despite having adequate total GWG.

Gestational weight trajectory and risk of adverse pregnancy outcomes among women with gestational diabetes mellitus: A retrospective cohort study

“…We identified three GWG trajectories using the latent class trajectory model among women with GDM and explored their associations with the risk of related adverse pregnancy outcomes. The percentages of three trajectories were 64.02%, 17.75% and 18.23%, respectively, in the study, which was not consistent with those among general pregnant women (Lin et al, 2023). The possible reason of the difference might be that for GDM pregnant women, they were asked to control weight gain during the third trimester.…”