Chronic hypertension and risk of placental abruption: is the association modified by ischemic placental disease?

The association between chronic hypertension and abruption is strong; ischemic placental disease (PIH and FGR) modified this relationship. These findings suggest an etiologic relationship between abruption and chronic placental disease. Chronic hypertension, if associated with LGA, is not associated with abruption; however, chronic hypertension with superimposed PIH accompanied by LGA is associated with significantly increased risk.