To the editor:
In reference to “New options in emergency contraception: A WHO study” by Philip D. Darney, MD (July 2003): The method of postcoital contraception described in this study (a single 1.5-mg dose of levonorgestrel) has been shown to be only about 75% effective.1,2 In a 1973 article, Blye reported using a 5-day regimen with essentially no failures.3
When diethylstilbestrol was taken off the market, Ovral (norgestrel/ethinyl estradiol) twice a day was found to be just as effective.4,5 There were reports of nausea, but clearly this was easier to treat than unwanted pregnancy.
With this data, I strongly recommend the 5-day regimen become standard of practice.
R.A. LANE, MD
SOUTH PADRE ISLAND, TEXAS
REFERENCES
- Diethylstilbestrol as a “morning after” contraceptive. Med Lett Drugs Ther. June 6 1973;15(14):58-59.
- Glasier A, Baird D. The effects of self-administering emergency contraception. N Engl J Med. July 1998;339:1-4.
- Blye RP. The use of estrogens as postcoital contraceptive agents. Clinical effectiveness and potential mode of action. Am J Obstet Gynecol. 1973;116:1044-1050.
- Kubba AA. Hormonal postcoital contraception. Eur J Contracept Reprod Health Care. June 1997;2:101-104.
- Creinin MD. A reassessment of efficacy of the Yuzpe regimen of emergency contraception. Hum Reprod. 1997;12:496-498.
Dr. Darney responds:
The effectiveness of emergency contraception is controversial. Reports on various regimens and different evaluation methods show a wide range of efficacy—from a slight decrease in expected pregnancy rates to 100% efficacy, as Dr. Lane notes. In all of them, compliance is a critical variable; thus, a simple regimen like the one supported by the World Health Organization data is likely to be more effective.