Compared with a 21/7-day cycle, continuous hormone exposure led to lighter menstrual flow; allowing hormone-free days reduced total days with bleeding or spotting.
The introduction of low-dose hormonal contraception has raised questions about the merit of monthly hormone-free intervals. In a study partially funded by industry, investigators recruited women who had previously been using oral contraceptives, vaginal rings, or transdermal patches in a 21/7 pattern (21 days of hormone exposure, 7 days off). All participants received vaginal rings to use according to a 21/7 regimen for at least 1 month to obtain baseline measurements, after which they were randomized to two continuous-use groups. Women in group one replaced their rings on the same calendar day monthly for 6 months, with no ring-free days; women in group two maintained the same pattern except that, if they experienced breakthrough bleeding …