Relationship between maternal gestational hypertension and home blood pressure in 7-year-old children and their mothers: Tohoku Study of Child Development

Women who had hypertensive disorders in pregnancy have an increased risk of cardiovascular diseases in later life. No studies, however, have investigated whether maternal hypertensive disorders in pregnancy affect self-measured blood pressure at home (HBP) in mothers and their children. We evaluated the association between maternal hypertension during pregnancy and HBP based on the prospective Tohoku Study of Child Development birth cohort study, which was performed in two areas in Japan. We included children in a singleton birth at term (36-42 weeks of gestation) with a birth weight of 42400 g. We collected prenatal care data from the medical charts. Because only two mothers experienced preeclampsia, we defined gestational hypertension (GH) as a hypertensive disorder in pregnancy. Seven years after birth, mothers and their children measured their HBP in the morning for 2 weeks. Of 813 eligible mothers, 28 (3.4%) experienced GH, and those were of a similar age compared with 785 non-GH mothers (37.3 vs. 38.0 years; P=0.41). Women with GH had higher body mass index (BMI) (23.8 vs. 21.4 kgm(-2); P=0.01) and elevated HBP (120.3/76.8 vs. 110.4/68.6mmHg; P<0.0002) 7 years after delivery. However, HBP was similar in children with and without GH mothers (93.5/55.9 vs. 94.1/56.1mmHg, P>0.38). These results were confirmatory in case-control (1: 2) analyses with matching by maternal age, maternal BMI before pregnancy, survey area and parity. In conclusion, maternal GH did not affect HBP in offspring but strongly affected maternal HBP even 7 years after birth.