Cycle control on low-dose oral contraceptives: a comparative trial.

Area of Science:

• Reproductive Health
• Pharmacology
• Gynecology

Background:

• Oral contraceptives (OCs) are widely used for birth control and cycle regulation.
• Different OC formulations, including monophasic and phasic types, vary in hormonal content and delivery.
• Understanding cycle control and side effect profiles is crucial for patient adherence and therapeutic success.

Purpose of the Study:

• To compare cycle control and side effect profiles of a monophasic OC (Loestrin) with three low-dose phasic OCs (Triphasil, Ortho 10/11, Ortho 7/7/7).
• To evaluate rates of intermenstrual bleeding (IMB), breakthrough bleeding (BTB), spotting, amenorrhea, leg cramps, and acne among users of different OC formulations.

Main Methods:

• A comparative study involving 391 women, with 300 completing 6 cycles of OC use.
• Participants used either Loestrin (monophasic) or Triphasil, Ortho 10/11, Ortho 7/7/7 (phasic).
• Data collected included rates of IMB, BTB, spotting, amenorrhea, leg cramps, and acne, with statistical analysis to compare groups.

Main Results:

• Intermenstrual bleeding (IMB) rates were comparable between Loestrin (31%) and phasic OCs (36-37%).
• Triphasil demonstrated significantly lower IMB rates than Ortho 10/11 and Ortho 7/7/7 in specific analyses (p<0.01).
• Spotting was more frequent with Ortho 10/11 and Ortho 7/7/7 compared to Triphasil (p<0.01); amenorrhea was more common with Loestrin, Ortho 10/11, and Ortho 7/7/7 (p<0.001).

Conclusions:

• While IMB rates were similar across most OCs studied, Triphasil showed an advantage in reducing IMB compared to specific Ortho formulations.
• Loestrin and other phasic OCs were associated with higher rates of amenorrhea, while Triphasil users experienced less acne and leg cramps.
• The choice of oral contraceptive may influence cycle control and the occurrence of specific side effects, impacting user experience and adherence.