Maternal weight gain among individuals with Type 2 diabetes and associated perinatal outcomes

Abstract

Objective The prevalence of type 2 Diabetes Mellitus (T2DM) in pregnancy is increasing, and adverse perinatal outcomes are common. We sought to assess whether higher or lower weight gain is associated with adverse perinatal outcomes in T2DM.

Study Design This was a retrospective cohort study of patients with T2DM and a singleton gestation who delivered at 2 health systems between 2018-2020. Demographics, markers of health care utilization, and various perinatal outcomes were abstracted from the medical record. Race and ethnicity were self-reported. Our primary exposure was weight gain < 5 kilograms(kg) across gestation compared to those who gained ≥5kg. We excluded patients for whom weight gain could not be calculated. We assessed multiple perinatal outcomes, and we used multinomial logistic regression to adjust for covariates.

Results We included 341 individuals with T2DM. There were 216/341 (63%) in the ≥5kg group, and 125/341 (37%) in the < 5kg group. The < 5kg group was more likely to be of Black race. The ≥5kg group initiated prenatal care earlier in gestation, were more likely to have ≥12 total prenatal visits, and be on insulin at the time of delivery. There were no significant differences in other demographics or markers of healthcare utilization (Table 1). Perinatal outcomes are shown in Table 2. Those with < 5kg of weight gain were less likely to develop a hypertensive disorder of pregnancy (aOR 0.3, 95% CI 0.2-0.5), or undergo a cesarean delivery (aOR 0.6, 95% CI 0.4-0.9). Stillbirth was more common among those who gained < 5kg (7 vs. 2%, p=0.02). There was a statistical difference in neonatal birthweight category (AGA vs. SGA vs. LGA) (p=0.04) between the 2 groups that did not persist after adjusting for covariates.

Conclusion Weight gain is associated with adverse perinatal outcomes among individuals with T2DM. While weight gain < 5kg is associated with a reduced risk for certain outcomes, the increased risk for stillbirth deserves further study.