Placental maternal vascular malperfusion and adverse pregnancy outcomes in gestational diabetes mellitus

Abstract

Introduction: Maternal vascular malperfusion (MVM) lesions represent hypoxic-ischemic damage to the placenta, and they are associated with adverse pregnancy outcomes. Women with gestational diabetes (GDM) are at increased risk for pregnancy complications, so we set out to characterize the prevalence and clinical correlates of MVM lesions in this cohort.

Methods: This was a retrospective cohort study of 1187/1374 (86.4%) women with GDM delivered between 2009 and 2012 who had placental pathology available. Placental lesions of all types were tabulated and grouped into constructs of related entities. MVM lesions specifically included villous infarcts, decidual vasculopathy, increased syncytial knots, perivillous fibrin, and fibrin deposition. We compared maternal characteristics between women with and without MVM lesions, and we also assessed the impact of these lesions on birth weight, preterm birth, and pre-eclampsia using multivariable logistic regression analysis.

Results: MVM lesions were the most common placental lesion type in women with GDM (n = 362, 30.5%). Excess gestational weight gain was independently associated with MVM lesions (aOR 1.42, 95% CI 1.06-1.91, p = 0.02) after adjusting for maternal characteristics. MVM lesions were associated with lower birth weight (-90.3 g, 95% CI -148.0 to -32.7, p = 0.002), as well as a 2-fold increased risk for delivery of a small for gestational age infant (10.8 vs 5.9%, p = 0.01) in overweight and obese women. MVM lesions were also associated with increased risk for preterm birth <34 weeks (adjusted OR 2.36, 95% CI 1.31-4.23, p = 0.004) and hypertensive disorders of pregnancy (HDP; adjusted OR 1.58, 95% CI 1.13-2.22, p = 0.02).

Discussion: Placental maternal vascular malperfusion lesions may be one pathway linking excess gestational weight gain to adverse pregnancy outcomes in women with GDM, and future studies are needed to identify metabolic factors that may explain this association.

Keywords: Gestational diabetes; Hypertensive disorders of pregnancy; Intrauterine growth restriction; Maternal vascular malperfusion lesions; Placenta; Preterm birth.