RESUMO
Objective To study on the relationship between the levels of homocysteine(HCY) ,folic acid and vitamin B12 and pregnancy-induced hypertension(PIH) in different pregnancies .Methods 539 pregnant women who registered for prenatal exami-nation of pregnant in the hospital were selected as research subjects .And there were 87 cases of PIH(PIH group) and 452 cases of normal pregnancy(normal pregnancy group) among them .The fasting blood samples were collected respectively in early pregnancy (8-10 weeks and 12-14 weeks of pregnancy) ,mid pregnancy(18 pregnancy weeks and 24 pregnancy weeks) ,and late pregnancy (30 pregnancy weeks and 36 pregnancy weeks) ,and the levels of HCY ,folic acid and vitamin B12 were measured .At the same time ,the supplements of folic acid and vitamin B12 and the incidence of PIH and birth defects were asked ,registered and checked . Results Compared with normal pregnancy group ,the serum HCY level of PIH group significantly increased in medium and late pregnancy periods (P0 .05) .In mid and late pregnancy periods , the serum HCY levels of PIH group and normal pregnant group negatively correlated with serum folic acid levels (r0 .05) .Conclusion In middle and late pregnancy periods ,if the serum HCY level of pregnant women increased ,the risk of PIH increased significantly .