Placental programming of blood pressure in Indian children

AIM To determine whether the size and shape of the placental surface predict blood pressure in childhood. METHODS We studied blood pressure in 471 nine-year-old Indian children whose placental length, breadth and weight were measured in a prospective birth cohort study. RESULTS In the daughters of short mothers (<median height), systolic blood pressure (SBP) rose as placental breadth increased (β = 0.69 mmHg/cm, p = 0.05) and as the ratio of placental surface area to birthweight increased (p = 0.0003). In the daughters of tall mothers, SBP rose as the difference between placental length and breadth increased (β = 1.40 mmHg/cm, p = 0.007), that is as the surface became more oval. Among boys, associations with placental size were only statistically significant after adjusting for current BMI and height. After adjustment, SBP rose as placental breadth, area and weight decreased (for breadth β = -0.68 mmHg/cm, p < 0.05 for all three measurements). CONCLUSIONS The size and shape of the placental surface predict childhood blood pressure. Blood pressure may be programmed by variation in the normal processes of placentation: these include implantation, expansion of the chorionic surface in mid-gestation and compensatory expansion of the chorionic surface in late gestation.