title: Fetal response to maternal methadone administration.
abstract: OBJECTIVE
  The purpose of this study was to investigate the effect of methadone on fetal neurobehavioral functions and maternal physiologic indicators.
  
  
  METHODS
  Forty women attending a substance abuse treatment facility with otherwise uncomplicated pregnancies were evaluated at peak and trough methadone levels. Fetal measures included heart rate, variability, periodic accelerations/decelerations, motor activity, and fetal movement-heart rate coupling. Maternal measures included maternal heart period, variability, electrodermal skin conductance, respiration, and respiratory sinus arrhythmia (RSA). Repeated measure analysis of variance was used to evaluate within-subject changes.
  
  
  RESULTS
  At peak methadone, fetal heart rate was slower, less variable, and displayed fewer accelerations. Fetuses displayed less motor activity, and the integration between heart rate and motor activity was attenuated. Maternal heart rate and skin conductance were unchanged, but methadone administration was associated with lower respiratory rate and RSA, an indicator of parasympathetic tone.
  
  
  CONCLUSIONS
  Maternal methadone administration has significant effects on fetal behavioral functions that are independent of maternal effects.
authors.affiliation: Department of Pediatrics, Johns Hopkins University School of Medicine, Baltimore, MD, USA. ljansson@jhmi.edu
authors.forename: Lauren M
authors.initials: LM
authors.lastname: Jansson
authors.forename: Janet
authors.initials: J
authors.lastname: Dipietro
authors.forename: Andrea
authors.initials: A
authors.lastname: Elko
mesh_terms: D000328:Adult; D000701:Analgesics, Opioid / Q000008:administration & dosage / Q000494:pharmacology*; D005260:Female; D005324:Fetal Movement / Q000187:drug effects; D005333:Fetus / Q000187:drug effects*; D006340:Heart Rate, Fetal / Q000187:drug effects; D006801:Humans; D008297:Male; D008691:Methadone / Q000008:administration & dosage / Q000494:pharmacology*; D009043:Motor Activity / Q000187:drug effects; D009293:Opioid-Related Disorders / Q000453:epidemiology; D011247:Pregnancy; D011248:Pregnancy Complications / Q000453:epidemiology; D011256:Pregnancy Outcome
chemical_list: D000701:Analgesics, Opioid; D008691:Methadone