Association between gestational weight change trajectories and perinatal outcomes in twin pregnancies in China

This study aimed to identify gestational weight change trajectories and examine their association with perinatal outcomes.

Prenatal and delivery records of 3393 twin pregnancies were obtained from the China-US Collaborative Project for Neural Tube Defects Prevention, a large population-based cohort study. Generalized gestational weight gain (GWG) was calculated by dividing the total GWG by the length of gestation in weeks and multiplying by 37 weeks. Latent class growth modeling (LCGM) was used to identify GWG patterns. Multivariable logistic regression and generalized estimating equations (GEE) were used to analyze the associations between GWG trajectories and perinatal outcomes. The included adverse perinatal outcomes were preterm birth, low birth weight (LBW), small for gestational age (SGA), and large for gestational age (LGA).

The mean ± SD of GWG for underweight women was 17.87 ± 5.67 kg, 16.76 ± 6.22 kg for normal weight, 14.34 ± 6.60 kg for overweight, and 14.27 ± 4.94 kg for obese. Three gestational weight change trajectory groups were identified: low-increase (32.36%), moderate-increase (56.26%), and high-increase (11.38%). Compared to the moderate-increase group, the high-increase group showed a reduced risk of LBW (aOR 0.68, 95%CI 0.56, 0.83), and SGA (aOR 0.49, 95%CI 0.40, 0.60) but an increased risk of LGA (aOR 2.23, 95%CI 1.48, 3.35). No significant change was observed in the risk of preterm birth in the high-increase group. The low-increase group had a higher risk of preterm birth (aOR 1.66 95%CI 1.42, 1.94), LBW (aOR 2.44 95%CI 2.13,2.80), and SGA (aOR 1.32 95%CI 1.16, 1.51), with no significant difference in the risk of LGA (aOR 1.11 95%CI 0.78,1.58).

Distinct patterns of GWG in twin pregnancies are associated with varying risks of adverse perinatal outcomes. These findings highlight the importance of monitoring and managing GWG in twin pregnancies.