Yes, Combined Oral Contraceptive Pills Can Be Used as Emergency Contraception
Yes, combined oral contraceptive pills containing ethinyl estradiol and levonorgestrel can be used as emergency contraception, though they are less effective and cause more side effects than dedicated emergency contraceptive products. 1
Specific Dosing Regimen (Yuzpe Method)
The CDC guidelines explicitly list the combined estrogen and progestin regimen as one of four approved emergency contraception options in the United States 1:
- First dose: 100 μg ethinyl estradiol + 0.50 mg levonorgestrel
- Second dose: Same amount, taken 12 hours after the first dose
- Timing: Should be taken as soon as possible within 5 days of unprotected intercourse 1
This translates to specific numbers of regular birth control pills depending on the formulation—for example, 4 pills of certain 30 μg ethinyl estradiol formulations per dose 2.
Critical Limitations to Understand
Effectiveness Hierarchy
The combined pill regimen is the least effective emergency contraception option available 1:
- Copper IUD: Most effective (can be used up to 5 days post-intercourse)
- Ulipristal acetate (Ella): More effective than levonorgestrel, especially 3-5 days after intercourse 1
- Levonorgestrel alone (Plan B): More effective than combined pills 1
- Combined estrogen-progestin pills (Yuzpe method): Least effective option
Side Effect Profile
The combined pill regimen causes significantly more nausea and vomiting compared to levonorgestrel-only or ulipristal acetate 1. This is clinically important because vomiting within hours of taking the pills may reduce effectiveness.
When This Option Makes Sense
Use combined oral contraceptive pills as emergency contraception when:
- Dedicated emergency contraceptive products (Plan B, Ella) are unavailable
- Cost is prohibitive and the patient already has birth control pills
- Access to pharmacy or clinic is limited within the 5-day window
What NOT to Do
Do not use this as routine emergency contraception when better options are available. The FDA-approved dedicated products (levonorgestrel 1.5 mg as Plan B, ulipristal acetate 30 mg as Ella) are specifically formulated for emergency use and have superior efficacy and tolerability profiles 3.
Practical Prescribing Considerations
- Advance provision: Consider providing instructions for the Yuzpe method to patients who may have difficulty accessing emergency contraception, though dedicated products are strongly preferred 1
- Pregnancy testing: Not required before administration 4
- Follow-up: Advise pregnancy test if withdrawal bleeding doesn't occur within 3 weeks 5
- Obesity consideration: Levonorgestrel-containing methods (including the Yuzpe regimen) may be less effective in obese women 1
The evidence consistently shows that while combined oral contraceptive pills can function as emergency contraception through the Yuzpe method, they represent a backup option when superior alternatives are unavailable 6, 7, 8.