Patterns of gestational weight gain and birthweight outcomes in the Eunice Kennedy Shriver National Institute of Child Health and Human Development Fetal Growth Studies–Singletons: a prospective study

Abstract

Background Inadequate or excessive total gestational weight gain (GWG) is associated with increased risks of small- and large-for-gestational age births, respectively, but evidence is sparse regarding overall and trimester-specific patterns of GWG in relation to these risks. Characterizing the interrelationship between patterns of GWG across trimesters can reveal whether the trajectory of GWG in the 1st trimester sets the path for GWG in subsequent trimesters, thereby serving as an early marker for at-risk pregnancies. Objective Describe overall trajectories of gestational weight gain across gestation and assess the risk of adverse birthweight outcomes associated with the overall trajectory and whether the timing of GWG (1st trimester versus 2nd/3rd trimester) is differentially associated with adverse outcomes. Study Design A secondary analysis of a prospective cohort of 2,802 singleton pregnancies from 12 U.S. prenatal centers (2009–2013). Small- and large-for-gestational age were calculated using sex-specific birth weight references <5th, <10th or ≥90th percentiles, respectively. At each of the research visits, women’s weight was measured following a standardized anthropometric protocol. Maternal weight at antenatal clinical visits was also abstracted from the prenatal records. Semiparametric, group-based, latent class, trajectory models estimated overall gestational weight gain and separate 1st and 2nd/3rd trimester trajectories to assess tracking. Robust Poisson regression was used to estimate the relative risk of small- and large-for-gestational age outcomes by the probability of trajectory membership. We tested whether relationships were modified by pre-pregnancy body mass index. Results There were 2,779 women with a mean (SD) of 15(5) weights measured across gestation. Four distinct gestational weight gain trajectories were identified based on the lowest Bayesian Information Criterion (BIC) value, classifying 10.0%, 41.8%, 39.2%, and 9.0% of the population from lowest to highest weight gain trajectories, with an inflection at 14 weeks. The average rate in each trajectory group from lowest to highest for 0 to <14 weeks was −0.20, 0.04, 0.21, and 0.52 kg/week and for 14 to 39 weeks was 0.29, 0.48, 0.63, and 0.79 kg/week, respectively; the 2nd lowest gaining trajectory resembled the Institute of Medicine recommendations and was designated as the reference with the other trajectories classified as low, moderate-high or high. Accuracy of assignment was assessed and found to be high (median posterior probability = 0.99, interquartile range 0.99–1.00). Compared with the referent trajectory, a low overall trajectory, but not other trajectories, was associated with a 1.55-fold (95% CI: 1.06, 2.25) and 1.58-fold (95% CI: 0.88, 2.82) increased risk of small-for-gestational age <10th and <5th, respectively, while a moderate-high and high trajectory, were associated with a 1.78-fold (95% CI: 1.31, 2.41) and 2.45-fold (95% CI: 1.66, 3.61) increased risk of large-for-gestational age, respectively. In a separate a...

Total and trimester‐specific gestational weight gain and infant anthropometric outcomes at birth and 6 months in low‐income Hispanic families

“…Sridhar et al found that both 2 nd and 3 rd trimester GWG rates above the IOM recommendations were associated with LGA, while only inadequate 2 nd trimester GWG rates were associated with SGA . Similarly, Pugh et al, identified four distinct GWG trajectories and observed that combined rates of GWG in the 2 nd and 3 rd trimesters, but not the 1 st trimester, strongly influenced infant size for gestational age . Women with low and high GWG trajectories during the 2 nd and 3 rd trimesters were more likely to have SGA and LGA infants, respectively, compared to women in the reference trajectory.…”

“…Weight gain in early pregnancy is primarily maternal fat gain and is associated with cord blood hormones related to offspring glucose and insulin regulation (during the 1 st trimester), while weight gain in later pregnancy is attributed to fetal, placental, and maternal gains and is associated with cord blood hormones related to offspring growth and adiposity (during the 2 nd trimester) . In general, findings from studies examining trimester‐specific GWG rates suggest that mid‐to‐late pregnancy GWG rates are more strongly associated with infant anthropometric outcomes compared to early and later pregnancy . Sridhar et al found that both 2 nd and 3 rd trimester GWG rates above the IOM recommendations were associated with LGA, while only inadequate 2 nd trimester GWG rates were associated with SGA .…”

“…Evidence varies regarding which trimester or pattern of GWG is most influential. GWG during mid‐ to later pregnancy, particularly the 2 nd trimester, has often been directly associated with offspring anthropometric outcomes . Higher GWG during the 1 st trimester has been positively associated with offspring weight or adiposity in some but not all studies, and other studies suggest significant roles for GWG in all three trimesters .…”

“…It is likely that trimester‐specific rates of GWG are independently and differentially associated with fetal growth outcomes and adiposity in later childhood . Evidence varies regarding which trimester or pattern of GWG is most influential.…”

Maternal weight gain and associations with longitudinal fetal growth in dichorionic twin pregnancies: a prospective cohort study

“…With early data collection from the prospective cohort, we were able to divide the early period of ,20 wk reported in previous studies into weight gain from 0 to 13 wk and 14 to 20 wk. We demonstrate that first-trimester weight gain in women with dichorionic twin pregnancies was not related to EFS or birth weight, which, notably, is consistent with singleton pregnancies (25). This may be reassuring to women who had an adequate prepregnancy nutritional status, but have limited firsttrimester weight gain because of the increased nausea and vomiting common in twin pregnancies (26).…”