Maternal and obstetric outcomes
Maternal and obstetric outcomes were compared between underweight, normal weight, overweight and obese women and between obesity classes (Tables 2 and 3). GDM was significantly associated with maternal weight in the comparison of all four weight groups (p  <0.001; Pearson’s coefficient C = 0.15). Obese mothers had a significantly higher risk for GDM when compared to underweight (p  = 0.003; OR = 0.36; 95% CI 0.19 – 0.7), normal weight (p  <0.001; OR = 0.32; 95% CI 0.23 – 0.43) and overweight (p  <0.001; OR = 0.47; 95% CI 0.33 – 0.69) mothers. Among obese mothers, there was a significantly higher rate for GDM in obesity class III when compared to obesity class I ( = 0.037; OR = 0.45; 95% CI 0.21 – 0.95). Wound healing disorders were significantly associated with both maternal weight in general ( <0.001; Pearson’s coefficient C = 0.09) and obesity (p  <0.001; Pearson’s coefficient C = 0.26). Obese women had a significantly increased risk for wound healing disorders compared to women of normal weight (p  <0.001; OR = 0.19; 95% CI 0.09 – 0.4), as well as mothers with obesity class III when compared to class I (p  <0.001; OR = 0.05; 95% CI 0.01 – 0.23). Preterm delivery was not associated with maternal weight or obesity. Nonetheless, mothers with obesity class III had the highest rate of delivery between 32 and 36+6 weeks of gestation (56%, compared to 40% in class I) in the obesity comparison. Interestingly, in the overall analysis, underweight mothers had the highest rate of delivery between 32 and 36+6 weeks of gestation (49%, compared to 42% in obese mothers). There was no significant association between maternal weight and preeclampsia or HELLP syndrome, IUD, and uterine atony with the necessity of Sulprostone or a Bakri balloon. Despite not being statistically significant, rates of PPH increased with rising BMI, albeit the highest rate occurring in obesity class I within the obese group. The normal weight and overweight groups had the highest rates of blood transfusions. There was no significant difference in rates of cesarean section or vaginal delivery between the weight groups or in the obesity analysis.