Only two studies examine cannabis use during breastfeeding, with conflicting results

A systematic review found only two studies meeting criteria for cannabis exposure during breastfeeding, with conflicting results on infant developmental outcomes, highlighting a major evidence gap.

RTHC-02757Systematic ReviewPreliminary Evidence2020RETHINKTHC RESEARCH DATABASErethinkthc.com/research

Quick Facts

Study Type
Systematic Review
Evidence
Preliminary Evidence
Sample
Not reported

What This Study Found

Despite cannabis being the most commonly used psychoactive substance by 5% of Canadian postpartum women, only two studies met inclusion criteria for developmental outcomes in breastfed infants exposed to cannabis. Results were conflicting, with one showing motor development effects and the other finding no significant impact.

Key Numbers

~5% of Canadian women use cannabis during pregnancy/postpartum; only 2 studies met inclusion criteria; results were conflicting.

How They Did This

Systematic review searching Medline, Embase, and PsychInfo for studies on infant outcomes from cannabis exposure during lactation, with developmental outcomes as inclusion criteria.

Why This Research Matters

Millions of breastfeeding women worldwide face decisions about cannabis use with almost no evidence to guide them. This review exposes just how little we actually know.

The Bigger Picture

THC is known to transfer into breast milk, but the evidence on what this means for infant development is essentially nonexistent. Clinical recommendations are being made on the basis of precaution rather than data.

What This Study Doesn't Tell Us

Only 2 eligible studies found; both were older and limited by methodology; cannot account for other substance co-exposures; no data on neurodevelopment beyond first year in included studies.

Questions This Raises

  • ?Should cannabis-using mothers avoid breastfeeding entirely?
  • ?How long after cannabis use is breast milk safest for infants?

Trust & Context

Key Stat:
Only 2 studies exist on cannabis during breastfeeding and infant outcomes
Evidence Grade:
Preliminary: systematic methodology but only 2 eligible studies with conflicting results.
Study Age:
Published 2020.
Original Title:
Cannabis Use During Lactation: Literature Review and Clinical Recommendations.
Published In:
Journal of obstetrics and gynaecology Canada : JOGC = Journal d'obstetrique et gynecologie du Canada : JOGC, 42(10), 1248-1253 (2020)
Database ID:
RTHC-02757

Evidence Hierarchy

Meta-Analysis / Systematic ReviewCombines many studies into one answer
This study
Randomized Controlled Trial
Cohort / Case-Control
Cross-Sectional / Observational
Case Report / Animal Study

Analyzes all available research on a topic using a structured method.

What do these levels mean? →

Frequently Asked Questions

Is it safe to use cannabis while breastfeeding?

The evidence is insufficient to answer definitively. Only two studies exist on infant outcomes, with conflicting results. THC does transfer into breast milk, so precautionary advice is to abstain or minimize use.

How long should you wait to breastfeed after using cannabis?

The authors recommend avoiding breastfeeding within 1 hour of inhaled cannabis use to reduce exposure during peak concentration. However, THC can persist in breast milk longer due to its fat solubility.

Read More on RethinkTHC

Cite This Study

RTHC-02757·https://rethinkthc.com/research/RTHC-02757

APA

Ordean, Alice; Kim, Gloria. (2020). Cannabis Use During Lactation: Literature Review and Clinical Recommendations.. Journal of obstetrics and gynaecology Canada : JOGC = Journal d'obstetrique et gynecologie du Canada : JOGC, 42(10), 1248-1253. https://doi.org/10.1016/j.jogc.2019.11.003

MLA

Ordean, Alice, et al. "Cannabis Use During Lactation: Literature Review and Clinical Recommendations.." Journal of obstetrics and gynaecology Canada : JOGC = Journal d'obstetrique et gynecologie du Canada : JOGC, 2020. https://doi.org/10.1016/j.jogc.2019.11.003

RethinkTHC

RethinkTHC Research Database. "Cannabis Use During Lactation: Literature Review and Clinica..." RTHC-02757. Retrieved from https://rethinkthc.com/research/ordean-2020-cannabis-use-during-lactation

Access the Original Study

Study data sourced from PubMed, a service of the U.S. National Library of Medicine, National Institutes of Health.

This study breakdown was produced by the RethinkTHC research team. We analyze and report published research findings without making health recommendations. All interpretations are based solely on the published abstract and study data.