Providing adolescents with advance doses of emergency contraception neither increases their likelihood of having unprotected sex nor negatively affects their use of condoms or hormonal contraceptives, according to a longitudinal study of 15-20-year-old women in Pennsylvania.1 Moreover, adolescents who have been provided with an advance dose of emergency contraception use it significantly sooner than those who have been educated about the method but must obtain it from a provider after unprotected sex.
The study included 301 sexually active women aged 15-20, who were recruited at a hospital-based adolescent health clinic in urban Pennsylvania in 1997-2001. Participants completed baseline interviews and were randomly assigned to either a control or an intervention group. All participants received instruction on how to obtain and use emergency contraception, and those in the intervention group were given one advance dose and access to two additional doses upon request at any time during the study.
In six monthly follow-up interviews conducted over the telephone, participants were asked about instances of unprotected sex, contraceptive use and method choice during the past month and at last sex. Follow-up interviews also addressed emergency contraceptive use and newly identified pregnancies and sexually transmitted diseases. The researchers used appropriate statistical tests to examine differences between the intervention and control groups at the bivariate level and constructed logistic regression models to identify independent predictors of emergency contraceptive use.
At baseline, the control and intervention groups did not differ significantly with respect to their demographic and reproductive health characteristics. The majority of participants were black (57%), were attending high school (59%) and lived in their family home (72%); nearly half received publicly funded health insurance coverage. The women’s mean age was 17 years, and their mean age at first sex was 15. Seventy-five percent of participants reported having used a contraceptive at last sex; 73% had used a condom. Sixty-nine percent had heard of emergency contraception, 20% had ever been pregnant and 30% had had a sexually transmitted disease.
One month after enrollment, adolescents’ use of condoms and regular hormonal contraceptives did not vary significantly between the intervention and control groups: In the past month, 28-32% had had unprotected sex, 68-70% had used condoms and 39-42% had used a hormonal contraceptive; at last intercourse, 19-20% reported having used no protection, 78-79% condoms and 39-41% hormonal contraceptives. These proportions remained generally consistent at the six-month follow-up, but condom use in the past month became significantly more common among women in the intervention group than among controls (77% vs. 62%).
However, the women differed in their use of emergency contraception: At one month, a significantly higher proportion of women in the intervention group than of those in the control group had used emergency contraception (15% vs. 8%), although this difference was not significant at the six-month follow-up. Participants who had received an advance dose of emergency contraception reported a significantly shorter interval between unprotected sex and the start of treatment than those who had not received an advance dose (11 hours vs. 21 hours).
The researchers used separate regression models, all of which controlled for study group and contraceptive method, to assess independent predictors of emergency contraceptive use. One model controlled for unprotected sex, one for sexual and reproductive history, and one for awareness of and expected need for emergency contraception. Results of the second model revealed that women who had ever been pregnant had elevated odds of using emergency contraception at some point during the study (odds ratio, 3.5). No other significant predictions of emergency contraceptive use were identified.
The researchers acknowledge several limitations, including the fact that participants who received an advance dose had to return to the study office for additional doses, which may in part explain the similarities in use patterns between the two study groups at six months. They recommend that adolescents be provided with advance doses of emergency contraception, because "doing so increases the likelihood that it will be taken during the most effective time frame without having an adverse effect on sexual or contraceptive risk-taking behavior."
1. Gold MA et al., The effects of advance provision of emergency contraception on adolescent women’s sexual and contraceptive behaviors, Journal of Pediatric and Adolescent Gynecology, 2004, 17(2):87-96.