Triphasic oral contraceptives: review and comparison of various regimens.

OBJECTIVE

To review and compare the risk-benefit profile of triphasic oral contraceptives with that of low-dose monophasic oral contraceptives.

METHODS

Literature on currently marketed triphasics and monophasics.

METHODS

Healthy women of reproductive age.

METHODS

Comparison of the rationale for development, composition, mechanism, efficacy, menstrual cycle control, side effects, health benefits, and risk-benefit profile.

RESULTS

All triphasics contain ethinyl estradiol (0.025-0.040 mg/d) and one of several progestins in doses (0.05-1.0 mg/d) related to their relative potencies, which are substantially lower overall (total dose) than those in monophasics. The triphasics are highly efficacious. In general, menstrual cycle control and side effects are similar in both types, but triphasics containing the newer progestins (desogestrel, gestodene, and norgestimate) have better cycle control and a reduced incidence of androgenic side effects compared with those with norethindrone or levonorgestrel. Both triphasics and monophasics have minimal effects on carbohydrate and lipid metabolism and hemostasis parameters, and therefore comparable low risks of coronary heart disease. The health benefits of triphasics and monophasics are similar and include decreased incidence of unwanted and ectopic pregnancies, ovarian cysts, endometrial and ovarian cancers, benign breast disease, and acute pelvic inflammatory disease; less menstrual blood loss and iron deficiency anemia; and lower frequency of irregular bleeding and menorrhagia.

CONCLUSIONS

The risk-benefit profiles of both triphasics and monophasics are favorable and similar.