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Substance Use in Breastfeeding Parents: A Review of Safety and Guidelines

Last updated: September 13, 2018
Project Number: RC1015-000
Product Line: Rapid Response
Research Type: Drug
Report Type: Summary with Critical Appraisal
Result type: Report


  1. What is the safety regarding the consumption of controlled and illicit substances by breastfeeding parents for the parent and infant?
  2. What are the evidence-based guidelines regarding the consumption of controlled or illicit substances by breastfeeding parents?

Key Message

The review was limited by the sparsity of evidence identified. Two non-randomized studies at high risk for bias were identified regarding the safety of parental postnatal alcohol consumption (by the breastfeeding parent) for the infant. These studies suggested that alcohol consumption by a breastfeeding parent may be associated with certain developmental markers (i.e., reduced weight centile and lower verbal IQ at ages 6-8 years, personal-social interaction developmental delay at 12 months of age), and not associated with others (i.e., no change in occipitofrontal circumference centile, palpebral fissure length centile, or total dysmorphology score at ages 6 to 8 years; communication, gross motor, fine motor, problem solving, personal-social interactions at 8 months post-partum; or communication, gross motor, fine motor, and problem solving at 12 months). For children with identified FASD, postnatal alcohol consumption by the breastfeeding parent (amount and frequency of consumption not reported) appeared to be associated with total dysmorphology score but not weight centile, OFC centile, palpebral fissure length centile, or verbal IQ score. No evidence was identified regarding the effects of using other substances on breastfed infants and no evidence regarding the safety of the breastfeeding parent was identified. One high quality evidence based guideline regarding parents with alcohol and/or substance dependence recommends breastfeeding unless the risks clearly outweigh the benefits (conditional recommendation), advising and supporting breastfeeding parents with substance abuse or dependence who use alcohol or drugs to cease using these substances (strong recommendation), and encouraging breastfeeding for those who are stable on opioid maintenance treatment with methadone or buprenorphine unless the risks clearly outweigh the benefits (strong recommendation).