Maternal vascular malperfusion of the placental bed associated with hypertensive disorders in the Boston Birth Cohort

Introduction The associations of maternal conditions, before or during pregnancy, with placental lesions have not been adequately studied in populations. Methods In the Boston Birth Cohort, we evaluated associations between three maternal medical conditions (hypertensive disorders [HDs], gestational/pre-gestational diabetes and obesity), and placental histological findings, using a standardized classification system proposed by the Amsterdam Placental Workshop Group. Placental pathology diagnoses and clinical data from 3074 mothers with clinical indications who delivered singleton live births at the Boston Medical Center between October 1998 and November 2013 were evaluated. Associations between each maternal condition and maternal vascular malperfusion (MVM) of the placental bed and its standardized subgroups were examined using multivariate logistic and multinomial regressions. Results Women with HDs (chronic hypertension, eclampsia, preeclampsia, HELLP syndrome) had significantly increased odds of MVM lesions when compared to women with no HD (aOR 2.08 95% CI 1.74–2.50), after adjusting for demographics, substance use, diabetes and body mass index. No significant differences in frequencies or aORs were seen in women with and without diabetes, or across body mass index categories. Co-morbid condition patterns that included HDs were more likely to be associated with MVM than those without. Discussion Using a standardized classification system, we showed that MVM is strongly and specifically associated with maternal HDs, but not other maternal conditions. Additional studies are needed to confirm and validate our findings, and evaluate the role of maternal vascular lesions of the placental bed in relation to postnatal growth and development of the offspring and effect modifiers.