Use of hormonal methods of birth control among sexually active adolescent girls

To identify factors associated with the use of various birth control methods among sexually active adolescent girls.

A survey distributed as part of a larger study measuring compliance with hepatitis B vaccination.

A hospital-based and a school-based clinic.

Demographic and health behavior data including sexual activity, contraceptive method, substance use, condom use, and history of sexually transmitted diseases (STDs) were collected. Birth control method was confirmed by medical record review. Associations with the outcome variable of birth control method were analyzed using chi square, Kruskal-Wallis analyses of variance, and t-tests, followed by logistic regression analysis.

Among sexually experienced girls, 39% (n = 123) reported using oral contraceptive pills (OCPs), 5.4% (n = 17) used Depo-Provera (medroxyprogesterone acetate) or Norplant (levonorgestrel), and 55.6% (n = 175) used no hormonal method. Logistic regression analysis revealed that the factors most significantly associated with the use of hormonal methods were older age (odds ratio [OR] = 1.19; 95% confidence interval [CI], 1.07-1.33), not using a condom at last intercourse (OR = 0.55; CI, 0.34-0.90), and having had a well visit within 1 year (OR = 2.11; CI, 1.12-3.70). OCP users were less likely than Depo-Provera or Norplant users to have used alcohol (p = 0.041), cigarettes (p = 0.002), or marijuana (p = 0.018) in the past 30 days. OCP users were less likely than nonusers of hormonal methods to have smoked cigarettes (p = 0.034) or marijuana (p = 0.052). The school-based clinic had a greater proportion of subjects using long-acting progestins (p < 0.001).

The decreased rate of condom use among those who used hormonal birth control methods and the different rates of health risk behaviors among users of various methods require targeted counseling efforts to decrease pregnancy and STD rates among young women.