Between 1997 and 2001, more than 300 young women ages 15 to 20 were enrolled in the study. They were given education about emergency contraceptive pills and received monthly follow-up telephone calls to assess sexual activity and their usage of various methods of contraception.
Study participants, who were followed for a period of six months, were randomized to receive emergency contraceptive education along with a package of emergency contraceptive pills or education only, with instruction on how to get the pills if they were needed. All participants were sexually active, with a mean age at first intercourse between 14 and 15 years.
Previously known as the "morning after pill," emergency contraceptives can reduce the risk of pregnancy by about 89 percent if taken within 72 hours of unprotected sex, according to Women's Capitol Corp., makers of Plan B™. Since the beginning of this study, the U.S. Food and Drug Administration has approved two forms of emergency contraceptive pills for sale by prescription Preven™ in 1998 and Plan B in 1999.
"At one- and six-month follow-up interviews, there were no differences between the groups in reported unprotected sex within that month," says Melanie A. Gold, D.O., lead study author and associate professor of pediatrics at the University of Pittsburgh School of Medicine, noting that there also were no differences by group in reported use of other hormonal contraceptives such as birth control pills or long-acting contraceptive injections at the one- or six-month follow-up interviews.