Women with insulin-treated diabetes are at significantly greater risk of preterm birth and of delivering babies who are large for gestational age (LGA), regardless of prepregnancy body weight, new findings suggest.
Researchers examined the role of maternal diabetes and weight on pregnancy outcomes in the population-based cohort study. The study comprised 649,043 live births in Finland between Jan. 1, 2004, and Dec. 31, 2014, including 4,000 in women with insulin-treated diabetes, 3,740 in women with type 2 diabetes, and 98,568 women with gestational diabetes.
Prepregnancy body mass index was normal for nearly 60% of mothers, while 4% were underweight, 21% were overweight, 8% were moderately obese, and 4% were severely obese.
Overall, the researchers found that women with insulin-treated diabetes had a 43-fold higher odds of having an LGA infant, compared with the reference group of women of normal BMI without diabetes (adjusted odds ratio [aOR], 43.80; 95% confidence interval, 40.88-46.93). And there was an 11-fold greater odds of having a preterm birth in this group (aOR, 11.17; 95% CI, 10.46-11.93).
The findings were published in JAMA Pediatrics.
“Smaller, but clearly statistically significant, increased LGA risks were found also for mothers with type 2 diabetes and gestational diabetes not treated with insulin, especially in combination with prepregnancy overweight or obesity that were stronger for type 2 diabetes than gestational diabetes,” wrote Linghua Kong, MSc, of the department of molecular medicine and surgery at Karolinska Institutet, and coauthors.
The aOR for LGA among women with type 2 diabetes was 9.57 (95% CI, 8.65-10.58), compared with the reference group. And for women with maternal gestational diabetes, the aOR for LGA was 3.80 (95% CI, 3.66-3.96).