Methadone maintenance treatment and the nonstress test.

The objective of this study was to determine whether long-term in utero exposure to methadone affects fetal performance on nonstress tests (NSTs). We retrospectively reviewed our experience with 28 women who were enrolled in an outpatient methadone maintenance program and received prenatal care at our institution. The median daily methadone dosage was 60 mg. NSTs (N = 106) were done during the third trimester in conjunction with prenatal visits. Reactivity was present in 79% of the NSTs. The proportion of NST results that were reactive in our population differed from the 86% overall reactivity rate reported in the literature (p < 0.05). This finding suggests that long-term in utero methadone exposure can affect fetal performance on the NST.