Participation in a program that helps families with one teen pregnancy prevent others

To define the optimal target population for a home- and clinic-based mentoring program designed to help one teen pregnancy-families prevent others, by prospectively determining who might be willing to participate in an intervention of this type.

Pregnant 13-to-19 year olds in a comprehensive, adolescent-oriented maternity program and their younger, nulliparous, 10-to-16 year old sisters were asked to participate in the intervention.

Only 27 (61%) of the 44 eligible families agreed to participate and 9 (33%) of these 27 families withdrew within 6 months. Older sisters from nonparticipating families were significantly more likely to be over 16 years of age at conception (53% compared to 15%; P =.01), and younger sisters from families that withdrew were significantly more likely to be over 14 years of age or under 12 years of age at enrollment (63% vs 22%; P =.03). Ultimately, 75% of the families in which the older sister was less than 17 years of age at conception joined the program and only 16% of the families in which the younger sister was 12-to-14 years of age at enrollment withdrew within 6 months.

Investigators testing the efficacy of programs for preventing pregnancies among teen mothers and their nulliparous, younger sisters could minimize selection bias by prospectively targeting families in which the older sister became pregnant before she was 17 years old and the younger sister is 12 to 14 years old.