The effect of gestational diabetes on maternal and neonatal outcomes

Women with gestational diabetes mellitus (GDM) are at increased risk of low blood sugar levels immediately after childbirth, and their babies are also at risk of macrosomia. Using the obstetric registry system in our hospital, we retrospectively assess the commonly occurring adverse maternal and infant outcomes in Taiwanese women with GDM.

We performed a hospital-based, retrospective cohort study. Women with singleton term pregnancy (≥37 weeks) aged 18-55 years at conception with live birth were identified from our registry from 2009 to 2022. Maternal outcomes included antenatal complications. Neonatal outcomes included macrosomia and birth defects. The dissimilarities between the GDM and non-GDM comparison groups, between age at conception younger or older than 35 years in infants with or without macrosomia, and between the macrosomic and the propensity-score matched non-macrosomic comparison groups were compared using the Pearson's chi-squared (χ²) test for categorical variables and student's t-test for continuous variables. Multiple logistic regression models were used to evaluate the risk of selected maternal and neonatal outcome variables in women with GDM and in women older than 35 years at conception, whereas conditional logistic regression model was used to control the unmatched confounders in infants with macrosomia. To minimize the confounding effects, a propensity-score matched macrosomia and non-macrosomia group based on the propensity score was created before applying the conditional logistic regression.

Among the 31,081 pregnant women included in our study cohort, one-sixth of them belonged to the GDM group (n = 5004). Compared to the non-GDM comparison group, pregnant women in the GDM group were more likely to be 35 years or older at conception with 37-38 weeks of gestation, overweight or obese, primiparous, conceived by assisted reproductive technology, holders of a university or postgraduate degree, and delivered in regional hospitals more frequently in the later years of study. After covariate adjustment, women in the GDM group were more likely to be associated with higher rates of hypertensive disorders, and their infants were associated with higher rates of fetal macrosomia and respiratory distress syndrome, even among younger women with normal body mass index (BMI).

The present study suggests that GDM is associated with increased risks of adverse maternal and neonatal outcomes, even among younger women with normal BMI.