Postpartum contraceptive use among adolescent mothers

To compare the incidence of repeat pregnancy and method continuation rate at 12 months postpartum in young women who chose either depot medroxyprogesterone acetate or oral contraceptives (OCs) as contraception.

We conducted a prospective cohort study of 122 postpartum women younger than 18 years of age who delivered between January 8, 1997 and December 31, 1997. Patients choosing depot medroxyprogesterone acetate (n = 76) and OCs (n = 46) were accrued for 12 months and were followed-up for a minimum of 12 months. Main outcome measures were median contraceptive method continuation and the incidence of repeat pregnancy at 12 months postpartum.

There was no difference in mean age at delivery (P =.47), parity (P =.84), or gravidity (P =.78) between depot medroxyprogesterone acetate and OC users. At 12 months postpartum, 27.4% of OC users and 55.3% of depot medroxyprogesterone acetate users were still using contraception. Median time to contraceptive discontinuation was longer for those choosing depot medroxyprogesterone acetate compared with OCs (17.8 vs 7.4 months, respectively, P =.002). The overall incidence of repeat pregnancy at 12 months postpartum was 10.6%. Among OC and depot medroxyprogesterone acetate users, respectively, 24% and 2.6% became pregnant again, producing a relative risk (RR) of 9.09 (95% confidence interval [CI] 2.1, 39.2) for repeat pregnancy among OC users. The mean time to repeat pregnancy (this was reported instead of the median time whenever the pregnancy rate had not reached 50% at the end of the follow-up period) was longer for depot medroxyprogesterone acetate compared with OC users (17.1 months vs 13.2 months, respectively, P <.001).

Adolescent mothers using depot medroxyprogesterone acetate injection for contraception have a higher method continuation rate and a lower incidence of repeat pregnancy at 12 months postpartum than those selecting OCs during the same period.