‘Increasingly common’ type 2 diabetes in pregnancy drives perinatal mortality risk

Key takeaways:

• Women with type 2 diabetes had greater neonatal and perinatal mortality risk vs. those with type 1 and gestational diabetes.
• Data suggest closer monitoring of pregnant women with type 2 diabetes is warranted.

Pregnant women with type 2 diabetes have a greater risk for perinatal mortality vs. pregnant women with type 1 diabetes, gestational diabetes and no diabetes, researchers reported in the American Journal of Obstetrics and Gynecology.

“(Type 2 diabetes) prevalence in the reproductive population has more than doubled in the past 15 years, overtaking type 1 diabetes as the leading cause of preexisting diabetes in pregnancy in the U.K.,” Naomi S. Clement, PhD, specialty trainee in the department of obstetrics and gynecology at the National Health Service in the U.K., and colleagues wrote. “In 2022, 55% of pregnancies complicated by pregestational diabetes were due to type 2 diabetes compared to 27% in 2003.”

In the systematic review and meta-analysis, Clement and colleagues identified 47 observational studies published from 2009 to 2024 reporting on congenital anomalies, stillbirths, neonatal and perinatal mortality, birth weight, large for gestational age or small for gestational age rates or macrosomia among pregnant women with type 2 diabetes. Researchers evaluated the impact of preexisting type 2 diabetes on pregnancy outcomes compared with type 1 diabetes, gestational diabetes and nondiabetes pregnancies.

Overall, 84,421 women had type 2 diabetes, 34,751 women had type 1 diabetes, 243,243 women had gestational diabetes and 5,398,613 women had a pregnancy without diabetes.

Compared with pregnant women with type 1 diabetes, those with type 2 diabetes were more likely to deliver small for gestational age infants (OR = 2.52; 95% CI, 1.24-5.1) and had greater risks for neonatal mortality (OR = 1.53; 95% CI, 1.2-1.94) and perinatal mortality (OR = 1.31; 95% CI, 1.07-1.61). In addition, compared with pregnant women with gestational diabetes, those with type 2 diabetes were more likely to deliver large for gestational age infants (OR = 3.49; 95% CI, 2.49-4.89), infants with congenital anomalies (OR = 1.91; 95% CI, 1.04-3.5) and stillborn infants (OR = 16.55; 95% CI, 5.69-48.11) and had a greater risk for perinatal mortality (OR = 3.96; 95% CI, 3.38-4.64).

Pregnant women with type 2 diabetes were also more likely to deliver large for gestational age infants (OR = 2.79; 95% CI, 1.93-4.04), infants with congenital anomalies (OR = 1.76; 95% CI, 1.11-2.79) stillborn infants (OR = 7.27; 95% CI, 3.01-17.53) and had a greater risk for perinatal mortality (OR = 4.18; 95% CI, 2.91-6.01) compared with pregnant women without diabetes.

“The fact that type 2 diabetes is increasingly common in women having children highlights that clinicians, researchers and policymakers need to be aware of these increased risks and work collaboratively with patient groups to optimize pregnancy outcomes and reduce longer-term health inequalities for both mothers and their children,” the researchers wrote. “Enhanced, supportive care for those with type 2 diabetes both before and during pregnancy is urgently needed.”