Relative to usual community services (group care or GC), MTFC has been shown to have positive and enduring effects on delinquency rates among girls mandated to out-of-home care, an extremely challenging clinical population (Chamberlain et al., 2007
). The present findings supported the hypothesis that MTFC also decreases pregnancy rates among these girls relative to GC. Specifically, the odds of getting pregnant for girls in GC were nearly 2 ½ times those of girls assigned to MTFC. Findings are remarkable for several reasons. First, MTFC girls were placed in less restrictive environments (i.e., community foster homes and greater exposure to normal daily life) than GC girls. Although the MTFC girls were highly supervised, they all attended public schools and had social interactions with community peers. In contrast, the GC girls were more often segregated from male peers1
and presumably had fewer opportunities to become pregnant during the intervention period. Second, the long-term outcomes from Trial 1 indicated that GC girls spent more time in locked settings (Chamberlain et al., 2007
), further decreasing their contact with males. Third, out-of-home care placements are among the most dramatic interventions possible for adolescents. Both GC and MTFC girls were removed from their families, schools, and peer groups, and both groups of girls showed significant reductions in delinquency over time (Chamberlain et al., 2007
). Thus, the significant effects of MTFC on delinquency and pregnancy are even more impressive, given that MTFC was compared against another active treatment.
MTFC effects on pregnancy are of high clinical relevance, given the ecological validity of the study, the effect size, and the extent of the problem in this high risk population. MTFC effects on pregnancy rates also would be expected to support overall cost-effectiveness, which—while not yet demonstrated for delinquent girls—has been estimated at a savings of $78,000 per male juvenile relative to GC (Aos, Miller, & Drake, 2006
). Findings also are important considering that few programs have demonstrated prevention of teenage pregnancy. It was not possible to identify mechanisms of the effects of treatment assignment on pregnancy, given measurement differences between trials, the lack of specificity regarding the timing of pregnancies, the lack of data collected on the reproductive services that girls at either site received, and limited statistical power. Exploratory analyses supported that the number of criminal referrals at baseline predicted pregnancy only among girls who received GC, suggesting that effects of MTFC on delinquency and pregnancy may occur through common mechanisms. Still, we can only speculate that one of more of the MTFC targeted processes (e.g., increased parental monitoring, reinforcement of positive behaviors, and support for academic achievement; see Leve & Chamberlain, 2007
) impacted girls’ deviant peer involvement, school engagement, and awareness of potential for different life outcomes; and that perhaps this sequence ultimately resulted in less, or less often unprotected, sexual intercourse.
It is notable that curriculum-based programs that directly target sexual behaviors and attitudes have generally failed to show reductions in pregnancy rates (Kirby, 2007
). The underwhelming results of carefully conceived programs may be due to difficulties in detecting low base rate events across relatively short periods. Yet, consistent with the present findings, several youth prevention programs that have demonstrated effects on pregnancy rates either have not focused on sexual behavior (Lonczak et al., 2002
) or have included sexual education as part of a broader youth development program (Allen, Philliber, Herrling, & Kuperminc, 1997
). These effective programs included components such as: parent and teacher training in behavior management; tutoring; promotion of school bonding; child social and emotional skill-building; mental, medical, and reproductive health care; and facilitation of employment and volunteerism.
These prior studies support the theory that altering general developmental pathways that lead to a host of negative outcomes might be more effective than exclusively targeting problem-specific behaviors, skills, and attitudes thought to be directly related to teen pregnancy. Framed somewhat differently, focusing prevention efforts on contexts that discourage pregnancy (e.g., those that adults monitor) may be more effective with this population than models that fully rely on adolescents’ agency (e.g. sex education). The present study did not directly test these important hypotheses. However, there was no evidence that the delivery of MTFC in Trials 1 and 2 (the latter of which included HIV-prevention components) differentially impacted the likelihood of pregnancy. Thus, one interpretation of these findings is that, for delinquent girls, a program that targets the general behaviors and contexts that underlie an array of problem behaviors may be effective at preventing pregnancy, while efforts to affect more proximal causes may not yield additional impact.
The predictive effects of study covariates also deserve discussion. First, a positive baseline pregnancy history increased the odds of a subsequent pregnancy by approximately three times. Though not surprising, this effect is notable given that approximately one quarter of the sample had been pregnant at study entry and given that the effect was not diminished by reports of sexual activity. Thus, teen pregnancy history, in addition to being a proxy for girls’ sexual activity, is itself a powerful indicator of risk. Second, girls who had more arrests at baseline were more likely to become pregnant during follow-up. This effect is consistent with multiple community-based studies of the association between risky sexual behavior and delinquency (e.g., Ary et al., 1999
). Third, older girls were no more likely than younger girls to become pregnant during follow-up. This remarkable null finding is likely explained by the severity of problems among girls who enter the juvenile justice system by early adolescence.
The present study requires replication and has some limitations. First, pregnancies were not medically verified. Second, results may not generalize to urban or more ethnically diverse samples of juvenile justice girls. A third limitation is that some assessors were not blind to group assignment at the 6-month follow-up, though it seems unlikely that assessor bias impacted girl or caregiver report of a pregnancy.
In conclusion, the prevention of teenage pregnancies is a national priority, and preventive interventions based on sexual education and abstinence have had limited success. The results of the present study indirectly support the theory that altering general problem behavior pathways that lead to delinquency may also reduce teen pregnancy among high risk adolescent girls. Given the economic and psychosocial burdens of teen childbearing and the very limited resources that girls in the juvenile justice system tend to bring to the task of parenting, the present effects of MTFC on pregnancy rates are of high public health significance.