Use of levonorgestrel implants versus oral contraceptives in adolescence: a case-control study.

OBJECTIVE

We compared continuation rates, effectiveness, satisfaction with method, side effects, and condom practices among adolescents using levonorgestrel implants (Norplant, Wyeth-Ayerst Laboratories, Philadelphia) as compared with oral contraceptives.

STUDY DESIGN

We conducted a case-control study comparing 94 adolescents < or = 18 years old who received Norplant between March 1, 1992, and Nov. 1, 1993 (cases), with 94 age-matched controls who selected oral contraceptives during this same time period. By use of a structured questionnaire, information was obtained on pregnancy status, duration of use, patient satisfaction, side effects, and condom practices 6 months after initiation. Objective measures included weight on Norplant and oral contraceptive users and hematocrit on implant patients.

RESULTS

Forty (43%) oral contraceptive patients compared with no Norplant patients discontinued their selected method before the 6-month interview (p = 0.00). Six patients prescribed oral contraceptives became pregnant. Ninety-three percent of Norplant users expressed overall satisfaction despite experiencing menstrual irregularity and cramping, amenorrhea, nervousness, abnormal hair growth or loss, rashes, and an increase in appetite more often than oral contraceptive users. Although Norplant patients also reported an increase in the duration of menstrual flow and number of days of spotting more often than oral contraceptive users, evaluation of hematocrits in these patients demonstrated a significant increase over the 6-month period (p = 0.00). Assessment of condom practices since initiation demonstrated that Norplant patients used condoms less often than oral contraceptive users (p = 0.00).

CONCLUSION

Use of levonorgestrel implants may cause more side effects than oral contraceptives in the early months after initiation but provide superior protection against unintended pregnancy. We concluded that Norplant is a reasonable alternative for adolescents, especially when compliance is an issue.