The Opioid Neonatal Abstinence Syndrome (NAS) is a term used to describe a cluster of signs and symptoms seen in infants experiencing withdrawal from opioid drugs. Despite a substantial literature the relationship between maternal methadone dose, NAS and the method of assessment of NAS symptoms has not been agreed. The following review will address current and historical controversies surrounding these issues and will examine the evidence concerned with the evaluation of neonates exposed to methadone in utero. The key findings are as follows: A variety of NAS scales are used to assess the severity of neonatal withdrawal symptoms including locally adapted validated tools. Inconsistencies in the use of NAS scales have included the timing, duration and frequency of administration; the degree to which observers were trained to reliability; the use of NAS scales designed for term neonates to assess pre-term neonates who may have a qualitatively different expression of abstinence symptoms and; the research setting in which the tool was administered. There is a lack of research investigating the observant bias' effect upon scoring NAS, the basis for treatment decisions and the influence of concomitant maternal use of non-opioid drugs late in pregnancy. We also discuss the implications of the lack of recognition of NAS symptoms leading to possible under reporting and inappropriate, early neonatal discharge from hospital. In addition, this paper also discusses the merits and problems of conducting research in this area and highlights gaps in our knowledge and areas for further research.

IntroductionOver the last decade a series of guidelines and recommendations have been published in the UK by the Department of Health, the Home Office, Professional and Non-Professional bodies. However, an optimal strategy and consensus in the management and care of opioid dependent pregnant users has yet to be established.ObjectivesDetermination of existing methods for identifying and managing pregnancy in opioid users prescribed methadone by NHS Treatment Services and regional differences.AimTo survey the management, treatment and follow-up of pregnant opioid users prescribed methadone by Drug Treatment Services in England and Wales.MethodsIn 2006 a POSTAL survey was conducted among 223 Community Drug Treatment Services (CDTS).ResultsSixty-six percent of CDTS responded to the survey (n = 154/233). A Chi-square, Mann_Whitney U Test and/or Kruskal-Wallis analysis revealed significant differences in the composition of CDTS and service provision across regions. Half of CDTS (55.3%) provided a methadone dosage regime lower than that recommended for non-pregnant drug users. There were also significant variations on how professionals approached the management of pregnant opioid users. CDTS with an addiction specialist were significantly more likely (p < .01) to advocate high doses of methadone whereas those with a midwife, obstetrician or social worker involved were more likely (p < .05) to suggest low dose methadone and/or detoxification.ConclusionsService provision for pregnant opioid users is comprehensive but there is still variability in some aspects of the treatment received. The way in which methadone is prescribed is not always optimal. Further work is required in this area.

We investigated the management and treatment of pregnant opioid users by Drug Treatment Services by region across England and Wales. A postal survey was conducted among 223 Community Drug Treatment Services (CDTS) across England and Wales. Sixtysix percent CDTS responded (n=154/233) to the survey. Over half CDTS (55.3%) provided a maintenance methadone dose lower than that recommended for non-pregnant drug users.There were significant variations across regions and how professionals approached the management of pregnant opioid users. CDTS with an addiction specialist were significantly more likely (p<.01) to advocate high doses of methadone whereas those with a midwife, obstetrician or social worker involved were more likely (p<.05) to suggest low dose methadone and/or detoxification. Service provision for pregnant opioid users is reliable and comprehensive but there is still variability in some aspects of the treatment received and the way in which methadone is prescribed is not always optimal.