Neonatal Abstinence Syndrome: Twelve Years of Experience at a Regional Referral Center

Infants exposed to opiates antenatally display withdrawal symptoms after birth referred to as neonatal abstinence syndrome (NAS).A total of 366 newborns (166 females, 10 twins) from 361 mothers were diagnosed with NAS from 2000 to 2011 at a single large metropolitan referral center.Retrospective chart review of all newborn infants exposed to opiates in utero.20% were premature (gestational age<37 weeks), 32% were small-for-gestational-age (<10^th percentile). 70% of infants (195/278) antenatally exposed to methadone (racemic methadone or levomethadone) required pharmacological treatment for 11 (1-55) days (median; range); however, 45% of infants (28/62) exposed to buprenorphine required pharmacological treatment for a median of only 5 (1-20) days (p=0.014). Pharmacological treatment of infants with phenobarbital (n=189) took a median of 9 (1-53) days, but treatment with morphine (n=39) took 19 (3-55) days (p<0.001). The median duration of hospitalization increased from 11 days in 2000-2004 to 19 days in 2008-2011 (p<0.001). The increased durations of neonatal hospitalization were associated with similar increases in the average dosages of maternal methadone.Use of buprenorphine, rather than methadone, for treatment of opiate-addicted pregnant women is associated with fewer and shorter neonatal withdrawal symptoms. The duration of hospitalization and treatment for NAS has increased over time.