Past oral contraceptive use and self-reported high blood pressure in postmenopausal women

BACKGROUND Studies have reported current hormonal contraceptive use is associated with adverse cardiovascular outcomes, including high blood pressure. The aim of this study was to determine the association between past hormonal contraception use and high blood pressure in Australian postmenopausal women. METHODS Women were recruited from the 45 and Up Study, an observational cross-sectional study, conducted from February 2006 to December 2009, NSW Australia. All of the variables used in this study were derived from self-reported data. These women reported being postmenopausal, having an intact uterus, and had given birth to one or more children. Odds ratios and 99% confidence intervals for the association between past hormonal contraceptive use and current treatment for high blood pressure, stratified by current age (<58 yrs, 58-66 yrs, and ≥67 yrs) were estimated using logistic regression, adjusted for income, country of origin, BMI, smoking, alcohol, exercise, family history of high blood pressure, menopausal hormone therapy use, number of children, whether they breastfed, and age of menopause. RESULTS A total of 34,289 women were included in the study. No association between past hormonal contraception use and odds of having high blood pressure were seen in any of the age groups (<58 yrs: odds ratio (OR) 1.1, 99% confidence interval (CI) 0.8 to 1.5, p = 0.36; 58-66 yrs: OR 0.9, 99% CI 0.7 to 1.1, p = 0.11; and ≥67 yrs: OR 0.9, 99% CI 0.8 to 1.0. p = 0.06). In women with a history of hormonal contraception use, no association between duration of hormonal contraception use and high blood pressure was observed. CONCLUSIONS Past hormonal contraception use and duration of use is not associated with high blood pressure in postmenopausal women.