Interest of Concentrations in Meconium of Buprenorphine and Methadone as a Prognostic Factor of NAS Outcome

Inclusion Criteria: * Aged over 18 years * pregnant women * Having agreed to participate in the study after information * Under opioid replacement therapy during pregnancy, in combination or not with other psychotropic drugs or legal or illegal substances. * Delivery after more than 34 weeks of amenorrhea Exclusion Criteria: * Pregnant women not receiving substitution treatment (methadone or buprenorphine). * Patient under substitution treatment delivering before 34 weeks of amenorrhea * Patient aged under 18 yrs old * Patient unable to understand the study (mental deficiency, impairment of consciousness, not French) or not accepting to answer the questionnaires. * Severe malformation syndrome or chromosomal abnormality in newborn discovered during pregnancy. * mother's death or newborn's death