Interventions to reduce unintended pregnancies among adolescents: systematic review of randomised controlled trials.
OBJECTIVE
To review the effectiveness of primary prevention strategies aimed at delaying sexual intercourse, improving use of birth control, and reducing incidence of unintended pregnancy in adolescents.


METHODS
12 electronic bibliographic databases, 10 key journals, citations of relevant articles, and contact with authors.


METHODS
26 trials described in 22 published and unpublished reports that randomised adolescents to an intervention or a control group (alternate intervention or nothing).


METHODS
Two independent reviewers assessed methodological quality and abstracted data.


RESULTS
The interventions did not delay initiation of sexual intercourse in young women (pooled odds ratio 1.12; 95% confidence interval 0.96 to 1.30) or young men (0.99; 0.84 to 1.16); did not improve use of birth control by young women at every intercourse (0.95; 0.69 to 1.30) or at last intercourse (1.05; 0.50 to 2.19) or by young men at every intercourse (0.90; 0.70 to 1.16) or at last intercourse (1.25; 0.99 to 1.59); and did not reduce pregnancy rates in young women (1.04; 0.78 to 1.40). Four abstinence programmes and one school based sex education programme were associated with an increase in number of pregnancies among partners of young male participants (1.54; 1.03 to 2.29). There were significantly fewer pregnancies in young women who received a multifaceted programme (0.41; 0.20 to 0.83), though baseline differences in this study favoured the intervention.


CONCLUSIONS
Primary prevention strategies evaluated to date do not delay the initiation of sexual intercourse, improve use of birth control among young men and women, or reduce the number of pregnancies in young women.
DiCenso
Alba
A
School of Nursing, McMaster University, 1200 Main Street West, Hamilton, Ontario, Canada L8N 3Z5. dicensoa@mcmaster.ca
Guyatt
Gordon
G
Willan
A
A
Griffith
L
L
D000293:Adolescent; D003268:Contraception Behavior / Q000706:statistics & numerical data; D005193:Family Planning Services / Q000706:statistics & numerical data; D005260:Female; D006293:Health Promotion; D006801:Humans; D008297:Male; D011247:Pregnancy; D011253:Pregnancy in Adolescence / Q000517:prevention & control*; D011320:Primary Health Care / Q000379:methods; D016032:Randomized Controlled Trials as Topic; D012746:Sexual Abstinence; D012725:Sexual Behavior