Abstract: Objective：To assess the association between combined norethisterone oral contraceptives（OC）and the risk of female hypertension so as to decrease the adverse reactions of OC. Methods：In June 2003， a cross-sectional study was conducted to invest the qualified and married women in Shaxi Town of Taicang County by unified questionnaire and physical examination tables. Logistic regression was used to analyze the prevalence factors of hypertension. Results：①The hypertension prevalence among 5 596 women was 12.10%（677 women）.② Compared with those subjects with IUDs, the risk of hypertension prevalence was increased slightly among those who had ever used OC over 20 years（adjusted RR=1.63， 95% CI was 1.17～2.27）， the risk was also slightly higher among those who was taking OC over 20 years（adjusted RR=1.80， 95%CI was 1.12～2.90）。③According to the standarded coefficient of regression, the risk factors of hypertension were ordered as: increased body mass index， family history of cerebrovascular diseases， age increasing， OC use， etc. Conclusions： There is an increase in the risk of hypertension among long?-term users of OC. The results suggested that follow-up of blood pressure and medical care should be strengthened in OC users，so as to improve the safety and efficiency of OC use.

Key words: Norethindrone, Contraceptives, oral, Combined, Contraceptive agents, female, Hypertension, Risk factors