The effects of methadone on maternal-fetal interactions in the rat.

ABSTRACT

Female Sprague-Dawley rats received methadone (25 mg/kg/day) by gavage throughout gestation. Water-gavaged rats served as controls. Fetuses were delivered by cesarean section when parturition was imminent. Our results indicate that methadone may interfere with fetal development and maternal-fetal interactions to some degree. The observed alterations were as follows fetal growth retardation, an interference with the triggering of parturition once normal delivery size is attained and possible positional malformations.