Newborn birth-weight of pregnant women on methadone or buprenorphine maintenance treatment: A national contingency management approach trial

BACKGROUND AND OBJECTIVES: Methadone maintenance treatment (MMT) is the gold standard for pregnant women with opioid use disorders. Still, low birth-weights were reported, in particular of mothers who became pregnant before admission to MMT. We studied whether an escalating incentive contingency-management approach may contribute to better newborn birth-weights. METHODS: A nationwide controlled randomized trial among all Israeli methadone/buprenorphine maintenance treatment (MBMT), newly or already in treatment pregnant women was performed. A modified contingency-management protocol with coupons of escalating value depending upon reduction of drug use, cigarette smoking, and alcohol consumption was compared to standard care arm. Drugs in urine, smoking (Fagerstrom score), alcohol use, and depression were monitored. RESULTS: Thirty-five women had 46 pregnancies. In their first pregnancy, 19 from the contingency-management and 16 from the standard care arms were studied. Contingency-management group as compared to the standard care arm included more newly admitted women (36.8% vs. 6.3%, p = .05), with benzodiazepine and cannabis onset at a younger age, and higher proportion of any drug abuse while pregnant (100% vs. 68.8%, p = .01). Fifteen of the contingency-management and 14 of the control arm gave birth (78.9% vs. 87.5%, p = .3) with similar proportions of normal (>2,500 g) birth-weight (71.4% vs. 61.5%, p = .8). CONCLUSIONS AND SCIENTIFIC SIGNIFICANCE: Newborns' birth-weight was comparable among the two study arms indicating no contribution of the contingency-management approach. Small sample and baseline differences between arms might have influenced results. Intensive intervention should be evaluated on a larger scale of participants. (Am J Addict 2017;26:167-175).