Evaluation of plasma levels of renin-aldosterone and blood pressure in women over 35 years treated with new oral contraceptives

Increases in blood pressure and weight are consequences of increased fluid retention following oral contraceptives administration. Hypertension and weight increase are particularly frequent in women over 35 years of age. The aim of the present study was to evaluate the clinical and hormonal effects of a new extra-low dose oral contraceptive [15 microg ethinyl estradiol (EE) and 60 microg gestodene (GSD)] on the renin-aldosterone system in a group of women aged 35-39 years treated for 3 months compared with a formulation containing the same hormones at a higher dose. Eighteen healthy women, age 35-39 years, were divided into two groups. The first group (10 women) used Arianna, Schering, 15 microg EE/60 microg GSD (EE15/GSD60); the second group (8 women) used Fedra, Schering, 20 microg EE/75 microg GSD (EE20/GSD75). Blood samples were obtained before the study and after 3 months of contraceptive use for assay of renin and aldosterone. Blood pressure was also measured on both occasions. No significant changes in plasma renin activity (PRA) or plasma concentrations of aldosterone were observed between the two groups after 3 months of contraceptive use. The mean increase in body weight after 3 months of contraceptive use was 350 +/- 100 g for EE20/GSD75 and 300 +/- 50 g for EE15/GSD60. There was a mean increase of 4 mm Hg for systolic pressure and 2 mm Hg for diastolic pressure in women on EE20/GSD75 and corresponding increases of 3 and 2 mm Hg in women on EE15/GSD60. The changes were not significant in any case. The results of the present study show that the formulations were well tolerated and provided good control of the menstrual cycle in all 18 women. The contraceptive formulations EE20/GSD75 and EE15/GSD60 have no clinical impact on blood pressure, PRA, or aldosterone in this age group.