How Cannabis Affects Fertility, Pregnancy, and Babies—A Complete Picture
A review of 64 studies found cannabis disrupts male fertility (sperm quality, testosterone), female reproduction (ovulation, placental function), and fetal development (birth weight, preterm risk)—affecting the entire reproductive process.
Quick Facts
What This Study Found
This review maps how cannabinoids interact with the reproductive system from conception through birth, covering territory that's usually examined in separate studies.
For men: cannabinoids interfere with spermatogenesis, reduce sperm motility and quality, and lower testosterone levels. These effects have been demonstrated in both clinical and experimental studies. For couples trying to conceive, this means cannabis use by either partner could affect fertility.
For women: cannabinoid-induced disruptions include negative effects on ovarian follicle maturation, ovulation, and placental function. The placental effects are particularly concerning because the placenta is the fetus's lifeline—disrupting its function can affect nutrient and oxygen delivery.
For fetal development: prenatal cannabis exposure is associated with reduced birth weight, preterm delivery, and developmental effects that can extend into childhood. These findings align with RTHC-00209's review specifically on neonatal outcomes.
The review emphasizes that the endocannabinoid system plays critical regulatory roles at every stage of reproduction—from sperm development through embryo implantation through placental formation through fetal brain development. Introducing exogenous cannabinoids disrupts a system that needs to function precisely during these processes.
Key Numbers
64 studies reviewed. Male effects: reduced spermatogenesis, sperm motility, sperm quality, and testosterone. Female effects: disrupted follicle maturation, ovulation, and placental function. Fetal effects: reduced birth weight, increased preterm risk, developmental impacts.
How They Did This
Non-systematic narrative review. Searched PubMed, Scopus, Web of Science, and Google Scholar in November 2024. After screening, 64 studies included covering cannabis effects on male fertility, female reproductive system, placental function, and prenatal/postnatal outcomes.
Why This Research Matters
Most reproductive cannabis research focuses on either male fertility, pregnancy outcomes, or fetal development in isolation. This review connects the entire reproductive arc, showing that cannabis doesn't just affect one stage—it can disrupt the process at every point from conception through delivery. For couples planning families, this comprehensive picture is more informative than any single study.
The Bigger Picture
This comprehensive view connects to the more focused studies: RTHC-00209 (neonatal outcomes specifically), RTHC-00191 (timing of prenatal exposure and amygdala effects), RTHC-00217 (cannabinoid effects on GABA neurodevelopment), and RTHC-00151 (reduced neonatal brain volume). The male fertility dimension adds an often-overlooked angle—while most pregnancy-cannabis research focuses on maternal use, paternal cannabis use may also affect conception.
What This Study Doesn't Tell Us
Narrative review with non-systematic search—may miss relevant studies. The 64 included studies vary widely in quality, methodology, and populations. Much of the evidence on fertility effects comes from animal studies or in vitro work. Human reproductive studies are confounded by polysubstance use, socioeconomic factors, and self-reported cannabis use. The review covers a very broad scope, limiting depth on any single topic.
Questions This Raises
- ?How long before conception should men and women stop cannabis to avoid reproductive effects?
- ?Are fertility effects reversible with cessation?
- ?Does the rising potency of cannabis products mean greater reproductive risk than what earlier studies captured?
Trust & Context
- Key Stat:
- Evidence Grade:
- Narrative review of 64 studies—comprehensive in scope but limited by non-systematic methodology and the predominantly observational evidence base.
- Study Age:
- Published in 2025 with literature searched through November 2024.
- Original Title:
- Effects of Phytocannabinoids on Reproductive System and Prenatal Development: Mechanisms and Clinical Implications.
- Published In:
- Journal of clinical medicine, 14(18) (2025) — The Journal of Clinical Medicine is a peer-reviewed journal known for publishing high-quality clinical research.
- Authors:
- Wesołowski, Michał, Sobaś, Aleksandra, Biedka, Kamil, Karwacki, Jakub, Bulski, Jakub, Błaszczyk, Katarzyna, Żełabowski, Kacper, Ziobro, Oliwia, Maj, Filip Jacek, Sornat, Karol, Estreicher, Agata, Klasa, Anna, Dłubak, Andrzej, Sebzda, Tadeusz
- Database ID:
- RTHC-07942
Evidence Hierarchy
Summarizes existing research without a strict systematic method.
What do these levels mean? →Read More on RethinkTHC
Cite This Study
https://rethinkthc.com/research/RTHC-07942APA
Wesołowski, Michał; Sobaś, Aleksandra; Biedka, Kamil; Karwacki, Jakub; Bulski, Jakub; Błaszczyk, Katarzyna; Żełabowski, Kacper; Ziobro, Oliwia; Maj, Filip Jacek; Sornat, Karol; Estreicher, Agata; Klasa, Anna; Dłubak, Andrzej; Sebzda, Tadeusz. (2025). Effects of Phytocannabinoids on Reproductive System and Prenatal Development: Mechanisms and Clinical Implications.. Journal of clinical medicine, 14(18). https://doi.org/10.3390/jcm14186494
MLA
Wesołowski, Michał, et al. "Effects of Phytocannabinoids on Reproductive System and Prenatal Development: Mechanisms and Clinical Implications.." Journal of clinical medicine, 2025. https://doi.org/10.3390/jcm14186494
RethinkTHC
RethinkTHC Research Database. "Effects of Phytocannabinoids on Reproductive System and Pren..." RTHC-07942. Retrieved from https://rethinkthc.com/research/wesolowski-2025-effects-of-phytocannabinoids-on
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.