Abstract: In total, we included 14 studies with 1298 participants: nine studies (704 participants) compared CM vs. control, and five studies (594 participants) compared MIB interventions vs. control. We did not find any studies that assessed other types of psychosocial interventions. For the most part, it was unclear if included studies adequately controlled for biases within their studies as such information was not often reported. We assessed risk of bias in the included studies relating to participant selection, allocation concealment, personnel and outcome assessor blinding, and attrition. The included trials rarely captured maternal and neonatal outcomes. For studies that did measure such outcomes, no difference was observed in pre-term birth rates (RR 0.71, 95% confidence interval (CI) 0.34 to 1.51; three trials, 264 participants, moderate quality evidence), maternal toxicity at delivery (RR 1.18, 95% CI 0.52 to 2.65; two trials, 217 participants, moderate quality evidence), or low birth weight (RR 0.72, 95% CI 0.36 to 1.43; one trial, 160 participants, moderate quality evidence). However, the results did show that neonates remained in hospital for fewer days after delivery in CM intervention groups (RR -1.27, 95% CI -2.52 to -0.03; two trials, 103 participants, moderate quality evidence). There were no differences observed at the end of studies in retention or abstinence (as assessed by positive drug test at the end of treatment) in any psychosocial intervention group compared to control (Retention: RR 0.99, 95% CI 0.93 to 1.06, nine trials, 743 participants, low quality evidence; and Abstinence: RR 1.14, 95% CI 0.75 to 1.73, three trials, 367 participants, low quality evidence). These results held for both CM and MIB combined. Overall, the quality of the evidence was low to moderate. The present evidence suggests that there is no difference in treatment outcomes to address drug use in pregnant women with use of psychosocial interventions, when taken in the presence of other comprehensive care options. However, few studies evaluated obstetrical or neonatal outcomes and rarely did so in a systematic way, making it difficult to assess the effect of psychosocial interventions on these clinically important outcomes. It is important to develop a better evidence base to evaluate psychosocial modalities of treatment in this important population.

Plain-language summary: Researchers from the Cochrane Collaboration examined the evidence published up to January 2015 and included 14 studies with 1298 pregnant women in this Cochrane review. The 1298 pregnant women received either CM or MIB techniques in adjunct to other comprehensive care options; women in the control group received usual care that included pharmacological treatment such as methadone maintenance, counselling, prenatal care, STD counselling and testing, transportation, and/or childcare. Nine studies used CM techniques vs. usual care, while five studies involved MIB techniques vs. usual care. All of the studies were completed in the United States of America and most participants were African American. Most studies used the Diagnostic and Statistical Manual of Mental Disorders (DSM-IV-R) criteria to determine drug dependence. There were no differences in retention or abstinence between CM or MIB techniques and usual care. There were also no differences in birth outcomes between the groups. Overall, there is low to moderate quality of evidence from the included studies. Allocation methods were often described in very limited manner. Furthermore, many studies lacked attrition information which could have impacted results. While further information related to these methods could be helpful, future randomized trials using psychosocial interventions are unlikely to show a benefit. In addition, there was significant heterogeneity in terms of methods for measuring outcomes.