Maternal methadone dosing schedule and fetal neurobehaviour

• Published in: The journal of maternal-fetal & neonatal medicine Vol. 22; no. 1; p. 29
• Main Authors: Jansson, Lauren M, Dipietro, Janet A, Velez, Martha, Elko, Andrea, Knauer, Heather, Kivlighan, Katie T
• Format: Journal Article
• Language: English
• Published: England 01.01.2009
• Subjects: Adult; Behavior - drug effects; Behavior - physiology; Cognition - drug effects; Cognition - physiology; Drug Administration Schedule; Female; Fetal Monitoring; Fetal Movement - drug effects; Fetus - drug effects; Fetus - physiopathology; Gestational Age; Heart Rate, Fetal - drug effects; Humans; Infant, Newborn; Maternal-Fetal Exchange - drug effects; Maternal-Fetal Exchange - physiology; Methadone - administration & dosage; Methadone - adverse effects; Narcotics - administration & dosage; Narcotics - adverse effects; Opioid-Related Disorders - physiopathology; Opioid-Related Disorders - rehabilitation; Pregnancy; Pregnancy Complications - physiopathology; Pregnancy Complications - rehabilitation
• ISSN: 1476-4954
• DOI: 10.1080/14767050802452291

Daily methadone maintenance is the standard of care for opiate dependency during pregnancy. Previous research has indicated that single-dose maternal methadone administration significantly suppresses fetal neurobehaviours. The purpose of this study was to determine if split-dosing would have less impact on fetal neurobehaviour than single-dose administration. Forty methadone-maintained women were evaluated at peak and trough maternal methadone levels on single- and split-dosing schedules. Monitoring sessions occurred at 36- and 37-weeks gestation in a counterbalanced study design. Fetal measures included heart rate, variability, accelerations, motor activity and fetal movement-heart rate coupling (FM-FHR). Maternal measures included heart period, variability, skin conductance, respiration and vagal tone. Repeated measure analysis of variance was used to evaluate within-subject changes between split- and single-dosing regimens. All fetal neurobehavioural parameters were suppressed by maternal methadone administration, regardless of dosing regimen. Fetal parameters at peak were significantly lower during single versus split methadone administration. FM-FHR coupling was less suppressed from trough to peak during split-dosing versus single-dosing. Maternal physiologic parameters were generally unaffected by dosing condition. Split-dosed fetuses displayed less neurobehavioural suppression from trough to peak maternal methadone levels as compared with single-dosed fetuses. Split-dosing may be beneficial for methadone-maintained pregnant women.