Associations between oral contraceptive use and risks of hypertension and prehypertension in a cross-sectional study of Korean women

BACKGROUND The effect of commonly used oral contraceptives (OCs) on blood pressure is still unclear. The aim of this study was to examine the relationship between OCs use and blood pressure and the prevalence of hypertension in a population-based sample of Korean women. METHODS A cross-sectional study was conducted using data from 3356 participants aged 35-55 years collected in the 2007-2009 Korea National Health and Nutrition Examination Surveys. OC use and demographic characteristics were obtained from participants using a questionnaire, and blood pressure was measured with a mercury sphygmomanometer. RESULTS Longer duration of OC use was positively associated with increasing levels of systolic blood pressure and diastolic blood pressure (p for trend <0.001). After adjusting for covariates, the odds ratio (OR) of hypertension was significantly increased in longer-term (>24 months) OC users (OR 1.96; 95% confidence interval (CI) 1.03-3.73) compared with those who had never used OCs. Additionally, use of OCs >24 months was associated with increased odds of prehypertension (adjusted OR 2.23; 95% CI 1.28-3.90) and hypertension or prehypertension (adjusted OR 2.13; 95% CI 1.37-3.32). CONCLUSION This study found a statistically significant association between OC use and blood pressure or hypertension among Korean women.