Twenty-four-day oral contraceptive regimens containing a progestogen with a long half-life shows higher contraceptive effectiveness under routine medical conditions compared with conventional 21-day regimens, according to research published in the January 2011 issue of Obstetrics & Gynecology.
Twenty-four-day oral contraceptive regimens containing a progestogen with a long half-life shows higher contraceptive effectiveness under routine medical conditions compared with conventional 21-day regimens, according to research published in the January 2011 issue of Obstetrics & Gynecology.
Jürgen Dinger, MD, PhD, and colleagues used outcome data from 52,218 US participants in the International Active Surveillance of Women Taking Oral Contraceptives, a large, prospective, controlled, noninterventional, long-term cohort study with active surveillance of participants to analyze contraceptive failure associated with the use of oral contraceptive pills.
Analyses were based on 1,634 unintended pregnancies during 73,269 woman-years of oral contraceptive pills exposure. Life-table estimates of contraceptive failure for a 24-day regimen of drospirenone and ethinyl estradiol and 21-day regimens of other progestogens were 2.1% and 3.5%, respectively, after the first study year, and 4.7% and 6.7%, respectively, after the third year. The adjusted hazard ratio was 0.7 (95% CI, 0.6–0.8). Direct comparisons of the 24-day and 21-day regimens of drospirenone and norethisterone, respectively, also showed lower contraceptive failure rates for 24-day regimens.
Obesity seems to be associated with a slight reduction of contraceptive effectiveness, according to researchers.
Is Arkansas’ New PBM Law the Right Path Forward for Reform? No One Knows Yet
May 9th 2025It could improve access to community pharmacies and lower prices. Or it will limit access to critical drugs and impact payers’ ability to contract for a broad range of services. Industry leaders are unsure about the impact of Arkansas’ law banning PBMs from owning pharmacies.
Read More