['Methadone maintenance is the standard of care for pregnant opiate addicts. However, withdrawal of an infant from methadone after birth often results in a lengthy hospital stay. This study identified potentially modifiable factors that are associated with the length of hospital stay of infants of mothers on methadone.', 'This study used a retrospective case series of patients from a university hospital in Texas. Eligible participants included 41 neonates born between January 1991 and December 1996 to mothers taking methadone at time of delivery. Charts were reviewed for factors relating to administration of opiates to the newborn, and the length of the hospital stay was recorded for each infant. Bivariate and multiple regression analyses were performed using length of hospital stay as the outcome measure.', 'Higher peak dose of tincture of opiate solution (TOS) and longer dosing interval were found to be related to longer length of hospital stay. These variables explained 23% of the variation in length of stay.'] Does shorter dosing interval of opiate solution shorten hospital stay for methadone babies?