Highest Dose Combination Birth Control Pills
Currently available combined hormonal contraceptives (CHCs) with the highest hormone content contain ≤50 μg of ethinyl estradiol combined with a progestin, as most modern formulations have reduced hormone doses to minimize side effects. 1
Understanding Combined Hormonal Contraceptives
Combined hormonal contraceptives contain both estrogen and progestin components:
Estrogen Component:
- Ethinyl estradiol (EE) is the most common estrogen in CHCs
- Current formulations typically contain 15-35 μg of EE
- Older, high-dose formulations contained up to 50 μg EE
- Newer formulations may use natural estrogens like estradiol valerate or estetrol 1
Progestin Component:
- Progestins are categorized by generations:
- First generation: norethindrone, ethynodiol diacetate (originally used in high doses)
- Second generation: levonorgestrel, norgestrel
- Third generation: norgestimate, desogestrel
- Fourth generation: drospirenone, dienogest 1
Highest Dose Formulations
The highest dose combination pills currently available contain:
- Estrogen: 50 μg ethinyl estradiol (maximum dose in modern formulations)
- Progestin: Varies by formulation, with first-generation progestins typically having higher doses
It's important to note that modern formulations have deliberately reduced hormone content compared to early oral contraceptives from the 1960s-1970s, which contained substantially higher doses of estrogens and progestins and were associated with greater side effects and complications 1, 2.
Dosing Regimens
CHCs are offered in multiple types of dosing regimens:
- Monophasic: Same dose of hormones in each pill
- Multiphasic: Varying weekly hormone doses to mimic the menstrual cycle
- Cyclic: Active hormone pills for 21-24 days followed by placebo pills for 7-4 days
- Extended cyclic: Active hormone pills for 84 days followed by placebo pills for 7 days
- Continuous: No hormone-free interval 1
Clinical Considerations
Safety Concerns with Higher Doses
- Higher estrogen doses are associated with increased risk of:
- Venous thromboembolism (VTE)
- Hypertension
- Cardiovascular events 1
- Historical data showed severe BP elevations with early high-dose CHCs, with mean BP of 170/100 mmHg in some cases 1
Contraindications for High-Dose Formulations
High-dose CHCs should be avoided in women with:
- History of venous thromboembolism or arterial thrombotic disease
- Breast or endometrial carcinoma
- Severe hypertension
- Diabetes with vascular involvement
- Migraine with aura
- Liver tumors
- Age ≥35 years who smoke 3
Modern Approach to Hormonal Contraception
The trend in modern contraceptive development has been to reduce hormone doses while maintaining efficacy:
- Lower doses minimize side effects and complications
- Newer progestins are designed to have fewer off-target effects
- Natural estrogens may have more favorable safety profiles 1, 4
Conclusion
While historically CHCs contained much higher hormone doses, current formulations with the highest hormone content contain ≤50 μg of ethinyl estradiol combined with a progestin. These higher-dose formulations should be used cautiously due to increased risk of cardiovascular and thrombotic complications.