Infant mortality among women on a methadone program during pregnancy

Abstract

Introduction and aims: The rate and correlates of infant death in those born to opioid-dependent women are unclear. This study aims to determine the infant mortality rate of infants born to women on a methadone program during pregnancy and to identify any modifiable risk factors.

Design and methods: A retrospective study of live births to all women in New South Wales, Australia during the period 1995-2002. Using record linkage four groups were compared: (i) live births to women on a methadone program during pregnancy who subsequently died during infancy; (ii) live births to women not on a methadone program who subsequently died during infancy; (iii) live births to women on a methadone program during pregnancy who did not die during infancy; and (iv) live births to women not on a methadone program who did not die during infancy.

Results, discussion and conclusion: The infant mortality rate was higher among infants whose mothers were on methadone during pregnancy (24.3 per 1000 live born infants in group 1 and 4.0 per 1000 live born infants in group 2) compared with infants of all other mothers. The single main cause of death for all infants was Sudden Infant Death Syndrome. There was a higher rate of smoking among women on methadone. The findings suggest that methadone and non-methadone infant-mother pairs have different symptom profiles, diagnostic procedures and/or different patterns of access to care.