Higher maternal doses of methadone does not increase neonatal abstinence syndrome

Objective: The purpose of this study is to assess the incidence of clinically significant neonatal abstinence syndrome (NAS) based on maternal antenatal methadone dosing in women with a history of narcotic dependence. Study design: A retrospective review of 174 pregnant women on methadone maintenance was performed. Data were stratified based on maternal methadone dose at delivery: low (0-50 mg/day, n = 59), medium (51-100 mg/day, n = 63), and high (>100 mg/day, a = 52). NAS was defined by Finnegan as score greater than 7 on two occasions. Outcome measures were rate and severity of NAS, birth weight, preterm birth rate, and neonatal morbidities and mortality. Results: The rates of NAS (40.7% vs. 52.4% vs. 40.8%, p > .05), birth weight, and neonatal morbidities were similar regardless of the maternal methadone dose. Although there was a trend toward earlier delivery, the rate of preterm birth among the three groups (low dose, 17%; medium dose, 19%; high dose, 27%; p > .05) was not statistically significant. Conclusion: Higher maintenance dosing of methadone is not associated with increased rate or severity of NAS or other adverse perinatal outcomes. Concerns about NAS should not restrict the methadone dosing during pregnancy. Methadone dosing should not be restricted to lower dosing during pregnancy. (C) 2011 Elsevier Inc. All rights reserved.