Most Common Formulation for Combined Oral Contraception
The most common formulation for combined oral contraceptives (COCs) contains ethinyl estradiol (EE) as the estrogen component in doses typically ranging from 30-35 μg combined with a progestin such as levonorgestrel or norgestimate. 1, 2
Estrogen Component
- Ethinyl estradiol (EE) is the most common estrogen component in COCs, with daily doses typically ranging from 10-50 μg 1
- Many providers begin with COCs containing 30-35 μg of ethinyl estradiol for optimal balance between efficacy and side effects 1, 2
- Lower doses of ethinyl estradiol are recommended to minimize potential cardiovascular risks 1, 2
Progestin Component
FDA-Approved COC Formulations for Acne
Four specific COC formulations have FDA approval for treating acne in women who desire contraception 1, 2:
- Norgestimate/ethinyl estradiol
- Norethindrone acetate/ethinyl estradiol/ferrous fumarate
- Drospirenone/ethinyl estradiol
- Drospirenone/ethinyl estradiol/levomefolate
Dosing Regimens
- COCs are available in several dosing regimens 1:
- Monophasic: same dose of hormones in each pill 1
- Multiphasic: varying weekly hormone doses to mimic the menstrual cycle 1
- Cyclic: active hormone pills for 21-24 days followed by placebo pills for 7-4 days 1
- Extended cyclic: active hormone pills for 84 days followed by placebo pills for 7 days 1
- Continuous: no hormone-free interval 1
Clinical Considerations
- First-line COCs typically contain levonorgestrel or norethisterone in combination with ethinyl estradiol 35 μg or less due to their effectiveness, relatively low risk of venous thromboembolism, and availability on formularies 3
- When combined with estrogen, all COCs yield net antiandrogenic properties, regardless of the specific progestin used 1
- Low-dose formulations (20 μg EE) coupled with levonorgestrel result in fewer side effects while maintaining cycle control comparable to higher-dose pills 4, 5
- The combined oral contraceptive remains the most commonly used contraceptive method in the United States 6
Safety Profile
- The absolute risk of venous thromboembolism with COC use is small (increases from 1 per 10,000 to 3-4 per 10,000 woman-years) compared to the risk during pregnancy 2
- Lower doses of ethinyl estradiol are associated with reduced cardiovascular risks 1, 2
- Progestin-only pills (POPs) are a valuable alternative for women who cannot use or choose not to use COCs due to estrogen-related contraindications or side effects 7
While various formulations exist, COCs containing 30-35 μg of ethinyl estradiol with either levonorgestrel or norgestimate represent the most commonly prescribed starting formulation, balancing efficacy, side effect profile, and safety considerations.