The use of drugs such as heroin, cannabis, amphetamines, hallucinogens, ecstasy, cocaine, alcohol and tobacco during pregnancy can result in a range of adverse effects.  Drug using women are at risk of suffering spontaneous abortions, hypertension, abruptio placentae, meconium stained liquor, precipitous and pre-term births and infections such as hepatitis C and HIV. 

In the developing fetus, DNA and RNA replication may be affected reducing head circumference, linear growth and birth weight. Other adverse effects include prematurity, still birth, and neonatal abstinence symptoms. Many pregnancies are unplanned.  Unplanned pregnancy has the potential to increase the incidence of postnatal psychological morbidity and affect mother/baby interactions. Less attention has been given to assessing the effects of the pharmacotherapies used to treat opioid dependent women during pregnancy. While methadone is considered the gold standard for treatment of these mothers other drugs are now available, one of which is buprenorphine.

Buprenorphine, marketed as Subutex, has only recently been released for use in Australia and is not recommended for use in pregnancy or breastfeeding. However a small but growing number of women are choosing to use the drug (either prescribed or obtained illegally). The limited international literature suggests that buprenorphine is safe to use during pregnancy, however it is important that the outcomes of these mothers and their infants are monitored closely.

Pilot Study of the Western Australian Register of Buprenorphine Use in Pregnancy and Early Postnatal Period

This study was designed to determine the duration and dose of buprenorphine exposure for opioid dependent mothers during pregnancy and six weeks postnatally; assess exposure to other pharmacotherapies such as methadone; monitor the obstetric and neonatal effects of buprenorphine; record the extent of other drug use during pregnancy and six weeks post-natally; compare the obstetric and neonatal outcomes with those of methadone mothers and infants in the HIT study; and make recommendations on the potential role of buprenorphine as a treatment option in the management of opioid dependent women during pregnancy and breastfeeding.

All eligible women (n=14) have been recruited to the study from the Chemical Dependency Clinic.  Recruitment has now ceased and the analysis is in progress. The results will add to the sparse clinical knowledge of the effects of the drug on pregnancy and infant outcomes.