New Study Links THC Consumption to Negative Effects on Female Fertility

A recently published study examined the effect of cannabis consumption on female reproductive health. Through clinical and in vitro analysis, researchers examined the impacts of tetrahydrocannabinol (THC) consumption on the human oocyte, finding that THC and its metabolites had negative effects on female fertility (1). As noted in the study’s introduction, previous research has shown that THC and its metabolites could reach the ovarian follicle. Additionally, while studies have been conduction on the effect of THC on sperm, and on cannabis use during pregnancy, studies have not been conducted on THC and the oocyte. The study, “Cannabis impacts female fertility as evidenced by an in vitro investigation and a case-control study,” was published in Nature Communications in September 2025.

As the study explains, when oocytes are collected for use in in vitro fertilization, their microenvironments are collected as well, which includes follicular fluid (FF) and supportive somatic cells (granulosa cells). Previous studies from these researchers suggest that THC may be able to affect the microenvironment where the oocyte matures.

THC and IVF: Case-Control Study Results

In the retrospective study, 1059 follicular fluid samples from patients undergoing in vitro fertilization were tested for THC concentrations. “In a case-control study, we show that follicular fluid THC concentration is positively correlated with oocyte maturation and THC-positive patients exhibit significantly lower embryo euploid rates than their matched controls,” the researchers state.

Other highlighted results include:

• 62 tested positive for the THC metabolite 11-COOH-THC (a 6% positivity rate)
• A positive correlation between Δ9-THC, 11-OH-THC and 11-COOH-THC and oocyte maturation was seen in the THC-positive group
• A negative correlation was seen between Δ9-THC levels and body mass index

How THC Affects Oocyte Development In Vitro

In this part of the study, donated oocytes were treated with one of two THC concentrations: one reflective of the metabolites that had been measured in the FF of IVF patients (95 oocytes total), and the other based concentrations in prior animal studies (93 oocytes total). A control group of 96 oocytes was included as well. Maturation of the oocytes was measured and compared.

Oocyte chromosome segregation errors and an increase in irregular spindle morphology was prompted by THC, the researchers stated. “In vitro, we observe a similar, but non-significant, increased oocyte maturation rate following THC exposure and altered expression of key genes implicated in extracellular matrix remodeling, inflammation, and chromosome segregation,” they also stated. THC affected transcripts for oocyte maturation processes, fertilization, early embryo development and implantation, though the mechanism THC uses to affect these processes is unknown.

Study Limitations and Implications for Patients

There were a few limitations noted. For instance, though the study was not reliant on self-reported data regarding cannabis use, the study did not collect data on consumption habits. The study population is also not necessarily representative of the general population. The results did not take into account the age of the patients, which is important in the ability of the oocyte to mature. Additionally, the presence of other drugs in the follicular fluid (FF) was not measured.

Overall, the results point to risks associated with THC consumption for patients undergoing in vitro fertilization. “Collectively, this data presents compelling evidence that cannabis consumption may negatively impact female fertility,” the researchers concluded. The researchers also stated that results from the study suggest that more information should be available to patients undergoing fertility treatments regarding the risks of cannabis use, along with the need for public health organizations to develop guidelines and recommendations on this issue for patients.

Reference

1. Duval, C.; Wyse, BA.; Fuchs Weizman, N.; Kuznyetsova, U.; Madjunkova, S.; Librach, CL. Cannabis impacts female fertility as evidenced by an in vitro investigation and a case-control study. Nat Commun. 2025. 16, 8185. DOI: 10.1038/s41467-025-63011-2.