Non-randomised trial, 1992
Does a new birth control pill with norgestimate control the menstrual cycle well?
Yes. Most women had normal bleeding patterns with minimal clinically insignificant changes in flow, cramps, and premenstrual tension. The large sample makes this strong, but no control group limits what we can conclude about the pill itself.
What they did
1,783 healthy women aged 17 to 38 took a triphasic oral contraceptive with norgestimate and ethinyl estradiol for up to 24 cycles at 33 sites in the United States. Researchers tracked 27,970 total cycles. Follow-up happened 3 to 4 months after treatment ended.
What they found
Most women experienced normal cyclic bleeding patterns. Variations in menstrual flow, dysmenorrhea, and premenstrual tension were minimal and clinically insignificant. Less than 1.0% of cycles after cycle 6 had failed withdrawal bleeding. No woman developed amenorrhea. The mean incidence of breakthrough bleeding was 2.36% in cycles 13 to 24.
What it means for you
This birth control pill effectively maintains normal menstrual cycles with few bleeding or cramping side effects. The study was large, but it had no control group or placebo, so we cannot know how much the pill itself causes these results versus what would happen otherwise.
1,783
Women in study
27,970
Menstrual cycles analyzed
2.36%
Breakthrough bleeding in cycles 13-24
About the study
- Original title
- Cycle control with triphasic norgestimate and ethinyl estradiol, a new oral contraceptive agent
- Authors
- Andolsek KM
- Journal
- Acta obstetricia et gynecologica Scandinavica. Supplement
- Year
- 1992
- Study design
- Non-randomised trial
- Participants
- 1,783
- What was tested
- Triphasic oral contraceptive with norgestimate and ethinyl estradiol for up to 24 cycles
- Read the paper
- doi.org/10.3109/00016349209156511
Topics
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