Drugs of abuse in maternal hair and paired neonatal meconium: an objective assessment of foetal exposure to gestational consumption

In a prospective sample of 80 mother-infant dyads, we investigated whether drugs of abuse in maternal hair measured during the pregnancy trimesters were also present in neonatal meconium. Principal drugs of abuse were analyzed in the three consecutive maternal hair segments and meconium samples by ultra-performance liquid chromatography tandem mass spectrometry assay. Of the 80 mothers, 32 (40%) presented one or more hair shafts with at least one of the analyzed drugs of abuse and/or its metabolites. The drug of abuse with a higher prevalence in our study population was methamphetamine: 19 mothers had methamphetamine in one or more hair segments (59.4%). The second most detected drug of abuse was cocaine; nine mothers presented cocaine in one or more hair segments (28.1%). Nineteen pregnant women consumed at least one drug of abuse during the first trimester, ten continued consuming drugs of abuse during the second trimester; and nine consumed until the end of pregnancy. Five of the nine newborns from mothers who consumed drugs during the whole pregnancy showed drugs of abuse in meconium samples. Newborns from the 23 remaining mothers with one or two hair shafts positive to drugs of abuse did not present drugs in their meconium. Indeed from these results, it seems that discontinuous and/or sporadic consumption during pregnancy could produce a negligible transplacental passage and hence negative results in meconium. Furthermore, the role of placenta in the metabolism and excretion of drugs of abuse is still to be precisely investigated. Copyright (c) 2015 John Wiley & Sons, Ltd.