[National epidemiological investigation of pregnancy induced-hypertension].

An epidemiological investigation of Pregnancy Induced Hypertension (PIH) in a population of 3.7 millions in China is reported in this paper. The incidence of PIH was 9.4%; that of mild moderate-PIH, pre-eclampsia, eclampsia and chronic hypertension with PIH were 4.7, 2.6, 1.7, 0.2 and 0.2% respectively. The maternal and perinatal mortality of PIH groups were higher than the group without PIH (P less than 0.01). Our results revealed that pathogenesis of PIH was positively related to age. Primiparity, multiple pregnancy, labour posture during pregnancy, physical labor intensity, maternal education level, body status, heredity and various complications during pregnancy.