In 2002-2005 67 women with buprenorphine dependence were followed up during pregnancy. Their pregnancies were uneventful. The prematurity rate was similar and there were no more major anomalies compared to the national statistics. The neonates were lighter compared to the national statistics. They were also born in good condition, with no perinatal hypoxia as defined by standard clinical parameters or certain biochemical markers in the cord blood. Almost 80% of newborns developed neonatal abstinence syndrome (NAS) and two third of them needed morphine medication for it. Maternal smoking over ten cigarettes per day aggravated and benzodiazepine use attenuated NAS. An infant’s highest urinary norbuprenorphine concentration during their first 3 days of life correlated with the duration of morphine treatment. The average length of infant’s hospital stay was 25 days. During 1992-2001 524 women were followed at special antenatal clinics due to substance abuse problems. According to register data mortality rate was 38-fold higher among cases than controls. The risk for violent or accidental death was increased. Cases had also elevated risk for viral hepatitis and psychiatric morbidity.