Post-coital contraception: an overview of published studies

Area of Science:

• Reproductive Health
• Pharmacology
• Contraception

Background:

• Post-coital contraception, or emergency contraception, is crucial for preventing unintended pregnancies after unprotected intercourse.
• Various hormonal and mechanical methods exist, but their comparative efficacy requires clear assessment.

Purpose of the Study:

• To pool data from published studies to evaluate the efficacy of different post-coital contraceptive regimens.
• To compare the failure rates of hormonal (ethinylestradiol, other estrogens, estro-progestin, danazol) and mechanical (IUD) methods.

Main Methods:

• Systematic review and meta-analysis of published studies on post-coital contraceptive methods.
• Pooled analysis of failure rates for different contraceptive regimens.

Main Results:

• Intrauterine devices (IUDs) demonstrated the lowest failure rate at 0.1% (1/879).
• High-dose ethinylestradiol showed a failure rate of 0.6% (19/3168).
• Other regimens had higher failure rates: other high-dose estrogens (1.1%), combined estro-progestin (1.8%), and danazol (2.0%).

Conclusions:

• Intrauterine devices (IUDs) and high-dose ethinylestradiol appear to be the most efficacious options for post-coital contraception.
• These methods are more effective than danazol or combined estro-progestin preparations.
• Limitations include potential over-representation of optimistic results and lack of direct comparative studies.