Hair analysis of opiates in mothers and newborns for evaluating opiate exposure during pregnancy

The increasing interest in toxicological hair analysis as a marker of human exposure to xenobiotics such as illicit substances or therapeutic drugs, has been made feasible by the extension of mass spectrometry, a highly sensitive method of detection. A newborn exposed to drugs in utero can suffer from a varying degree of withdrawal syndrome, a few days after birth. If of opiate origin, the withdrawal syndrome can be treated with morphine, among other therapeutics, but it is not easy to diagnose because of atypical symptoms presented by neonates and especially when maternal drug addiction has not been revealed. To assess and measure toxicological factors linked with the appearance and the severity of this syndrome, maternal and neonatal matrices such as urine, meconium and hair were collected during a protocol approved by the ethical committee. Opiates in particular were measured with GC-MS and potential combined dependences (cannabis, cocaine, amphetamine, LSD and benzodiazepines) and/or substitutive therapeutics (methadone or buprenorphine) were also assessed in 17 mother/neonate couples. Gestational opiate exposure profiles were drawn up and linked with the observed withdrawal syndromes. A withdrawal syndrome seems to appear more frequently after foetal exposure to an association of opiates/substitutive molecules (8 out of 10 withdrawal syndromes observed in this study), although the impact of cocaine and benzodiazepines must also be taken into account. The results obtained in neonatal hair make it possible to affirm foetal drug exposure and are in accordance, for the majority, with the appearance of a neonatal withdrawal syndrome (NWS). Neonatal hair analysis could contribute to assess in utero exposure to opiates, particularly when results in urine and meconium are negative or when these matrices are not available.