Previous non-diabetic pregnancy with a macrosomic infant – Is it a risk factor for subsequent gestational diabetes mellitus?

Aim: To examine the association between previous pregnancy neonatal birthweight (BW) among non-diabetic women and the rate of gestational diabetes mellitus (GDM) in the subsequent pregnancy. Methods: Case control study in a university affiliated medical center from 2005 to 2019. Women who had a singleton pregnancy and two consecutive deliveries in our medical center were included. GDM diagnosis was based on either National Diabetes Data Group or Carpenter and Coustan criteria. Univariate analysis was followed by multivariate logistic regression. Results: A total of 47,823 women were included. GDM incidence among the subsequent pregnancies was 2.7% (1,312 women). Parturients with GDM had higher mean birthweight in their previous pregnancy compared with parturients without GDM (3336.9 ± 587.4 vs 3229.9 ± 488.2 g, p < 0.001). Women with GDM in the subsequent pregnancy as compared to women without GDM showed higher rates of having previous big neonates: BW ≥ 90% for gestational age, BW ≥ 4000 gr and BW ≥ 4500 g (p < 0.01 for all), 20.2% vs. 10.7%, 9.6% vs 4.5% and 1% vs. 0.3% respectively. Multivariate analysis adjusted for known risk factors for GDM showed that these factors were still independently associated with occurrence of GDM in the subsequent pregnancy 1.7 (1.1–2.5), 1.9 (1.1–3.4), 6.0 (1.6–22.8), respectively. Conclusion: Neonatal BWs in previous pregnancy is associated with increased GDM incidence in the subsequent pregnancy; Women with previous macrosomia should possibly undergo a diagnostic testing.