Comparison of adverse obstetric outcomes and maternity hospitalization among heroin-exposed and methadone-treated women in Taiwan

Abstract

Aims: To identify sociodemographic and clinical factors predicting the overall risk of adverse obstetric outcomes and the length of maternal hospital stay among heroin-exposed and methadone-treated women in Taiwan.

Methods: Using the retrospective matched cohort study design, 396 births to women on methadone treatment during pregnancy (the methadone-treated group) and 609 to women who started methadone treatment after childbirth (the heroin-exposed group) were identified in the National Methadone Maintenance Program. Adverse pregnancy outcomes were assessed by still birth, low birth weight and preterm delivery. We used multivariate methods and zero-truncated negative binomial regression to evaluate association estimates.

Finding: Both heroin-exposed and methadone-treated women had 2-4-fold greater risk of adverse pregnancy outcomes. HIV infection increased the overall risk of adverse pregnancy outcome in the methadone-treated group, whereas being unmarried and having treatment history of substance use disorders increased such risk in the heroin-exposed group. Maternal ages at delivery and healthcare facility used had moderate effects on the length of maternal hospital stay; HIV infection significantly increased the length of hospital stay for women in the heroin-exposed group (adjusted relative risk=1.32, 95% CI=1.05-1.68).

Conclusions: Our results showed no appreciable differences in the occurrence of adverse obstetric outcomes and the length of maternity hospitalization between the methadone-treated and the heroin-exposed women; the profile of sociodemographic and clinical predictors was similar as well. Coordination of addiction treatment and prenatal care may help reduce unfavorable obstetric outcomes among female heroin addicts seeking substitution treatment.

Keywords: Low birth weight; Methadone; Pregnancy; Preterm.