How do premature babies exposed to opiates in utero withdraw? A comparison of withdrawal symptoms in preterm and term babies exposed to opiates in utero

© 2012 Niroshini PereraOBJECTIVE: The aim of this research is to discover the rate and pattern of withdrawal observed in premature babies exposed to opiates (heroin, methadone and buprenorphine) in utero. METHODOLOGY: To determine the incidence and severity of neonatal abstinence syndrome in term and preterm babies, a retrospective case note review was undertaken of all women who delivered at a tertiary obstetric hospital, from January 2003 to December 2007 inclusive, who were regularly using heroin, or prescribed methadone, or buprenorphine. Neonatal abstinence syndrome (NAS) was diagnosed using the modified Finnegan NAS scoring system. A control group of non-opiate-exposed mothers and babies matched for gestation, gender and postcode as a marker of socioeconomic status were also selected. Their postnatal course and incidence of co-morbidities was compared to the preterm opiate-exposed cohort. RESULTS: There were 149 opiate-exposed babies included in our study. 108 were term and 41 were preterm. The overall rate of NAS was 32.9%, with no significant difference between term and preterm babies. The mean gestation of those babies with NAS was 37.5 weeks. Those babies with NAS had significant difficulty in establishing feeding, particularly in the term group. Length of stay between preterm and term babies with NAS was comparable. Preterm opiate-exposed babies took significantly longer to regain their birth weight when compared to non-opiate-exposed controls. Length of stay in hospital was increased, only if neonatal abstinence syndrome was diagnosed. CONCLUSION: Opiate-exposed babies experience withdrawal across gestations. Preterm opiate-exposed babies take significantly longer to return to their birth weight. This could reflect stress, which manifests as poor weight gain