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Changes in methadone maintenance therapy during and after pregnancy
Brittany Albright1, Lesley de la Torre, Betty Skipper
1Department of Obstetrics and Gynecology, University of New Mexico School of Medicine, Albuquerque, NM 87131, USA.
Objective:
The aim of this study is to better understand anticipated changes in daily methadone doses as a guide for prescription during pregnancy.
Methods:
This retrospective case series involved a single cohort longitudinal design of 139 consecutively chosen women who began methadone therapy before 26 completed gestational weeks. Changes in the single daily dose were based on a standard opiate withdrawal scale and determined from early pregnancy until 6 weeks postpartum.
Results:
As gestation advanced, the methadone dose increased (86%) rather than remained the same (8%) or decreased (7%). This gradual increase in daily dose during pregnancy (mean increase = 24 mg, 95% confidence level = 20-28 mg) was statistically significant (p < .001) regardless of the initial maintenance dose. By the sixth postpartum week, most subjects (85%) took within 10 mg of their dose at delivery (mean change in dose = -4 mg, 95% confidence interval = -6 to -2 mg).
Conclusions:
Daily doses of methadone increased until the third trimester, then remained essentially unchanged through the sixth postpartum week.
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