METHODS: Pregestational (PGD) and gestational (GD) diabetes were identified based on International Classification of Diseases 9th revision codes using 2014 Louisiana Medicaid claims data merged with birth certificate data. Excessive weight gain, defined as having gained more weight than recommended by the 2009 Institute of Medicine guidelines, was identified by birth certificate data. Logistic regression was used to estimate adjusted associations of PGD and GD with outcomes of interest. Covariate selection was based on change-in-estimate criterion with a 10% cutoff and also selected out-of-convention. Estimated adjusted associations of excessive weight gain with outcomes of interest were calculated for those with PGD or GD. Limitations include the use of self-reported weight data.
RESULTS: Of 38,178 births, 4% of women had PGD and 8% developed GD. Of those with PGD or GD, 47% and 44% had excessive weight gain, respectively. Compared with non-diabetic mothers, those with diabetes had increased odds of cesarean delivery (PGD aOR=1.7,95%CI 1.5,2.0; GD aOR=1.3,95%CI 1.2,1.4), hypertension (PGD aOR=3.0,95%CI 2.6,3.4; GD aOR=1.5,95%CI 1.3,1.6), and antepartum hemorrhage (PGD aOR=1.3,95%CI 1.1,1.6; GD aOR=1.2,95%CI 1.0,1.3), while infants had increased odds of NICU admissions (PGD aOR=2.2,95%CI 1.9,2.7; GD aOR=1.3,95%CI 1.1,1.3). Odds of preterm birth was more than doubled for mothers with PGD (aOR=2.4,95%CI 2.1,2.8) than mothers without diabetes, while there was 30% increased odds of small-for-gestational age for GD (aOR=1.3,95%CI 1.2,1.5). Compared with diabetic mothers who met the recommended weight gain, excessive weight gain increased odds of cesarean delivery (PGD, aOR=1.5,95%CI 1.2,2.0; GD, aOR=1.5,95%CI 1.2,1.8) and hypertension (PGD, aOR=1.3,95%CI 1.1,1.7; GD, aOR=1.5,95%CI 1.3,95%CI 1.1,1.7). For those with GD, excessive weight gain lowered the odds of small-for-gestational age compared to normal weight gain (aOR=0.64,95%CI 0.53,0.79), while there was no association with large-for-gestational age (aOR=1.4,95%CI 0.64,3.2).
CONCLUSIONS: Louisiana pregnancies with Medicaid insurance complicated by diabetes had more adverse outcomes than those with no diabetes. Excessive gestational weight gain may account for a high proportion of cesarean deliveries and cases of hypertension in pregnancy complicated by diabetes. However, there may be consequences of weight gain for mothers developing GD that needs to be further explored.