News | Study suggests cannabis may harm male fertility more than cigarettes, raising concerns about a ‘hidden reproductive crisis’
A new study by Vijay Kumar Malesu and colleagues, published in Scientific Reports, found that both tobacco and cannabis have significant adverse effects on male fertility and sperm DNA integrity, with greater harm associated with cannabis.
Concerns about sperm health extend to the next generation
Male factors account for nearly half of infertility cases worldwide, while around 14% of couples face fertility difficulties and tobacco and recreational cannabis use continue to rise.
Tobacco smoke contains more than 7,000 chemicals, many known carcinogens and mutagens that directly damage sperm DNA. Tetrahydrocannabinol (THC), the active component of cannabis, can bind to receptors in sperm cells and significantly disrupt motility, viability, and morphology. Frequent cannabis use may also alter the sperm epigenome, potentially affecting offspring health.
Study design: comparison of three groups
Semen samples from 113 men were divided into nonsmokers (NS, 37), tobacco smokers (TS, 39), and cannabis smokers (CS, 37). Participants had no alcohol misuse, chronic disease, or genetic abnormalities.
Semen quality was assessed using World Health Organization (WHO) standards, including volume, sperm concentration, morphology, and motility. Fluorescent AO and CMA3 staining evaluated sperm DNA fragmentation and protein packaging, while PCR and Sanger sequencing examined variants in the mitochondrial genes MT-CO1, MT-CO2, and MT-CO3.
Key finding: sperm quality was poorest in the cannabis group
Results showed:
Normal morphology: 7.46% in nonsmokers, 5.02% in tobacco smokers, and 2.26% in cannabis smokers (p<0.001).
Non-progressive motility: 20.63% in the cannabis group, below 27.82% in the tobacco group and 34.40% in nonsmokers (p<0.001).
Immotile sperm: highest in the cannabis group (68.66%), followed by tobacco smokers (58.92%) and nonsmokers (51.73%) (p<0.001).
DNA fragmentation by AO staining: 28.53% in the cannabis group, compared with 6.4% in tobacco smokers and 10.1% in nonsmokers (p<0.001).
Protein-packaging defects by CMA3 staining: 37.13% in the cannabis group, compared with 25.3% in tobacco smokers and 15.0% in nonsmokers (p<0.001).
These measures indicate substantial structural and genetic sperm damage among cannabis users. Tobacco also harmed fertility, but cannabis was associated with more severe DNA damage and chromatin abnormalities, potentially affecting embryo development and pregnancy success.
Genetic analysis: no mutations identified, but epigenetic effects may exist
Researchers detected 23, 15, and 30 single-nucleotide polymorphisms (SNPs) in the three mitochondrial genes, but distribution did not differ significantly between groups (MT-CO1, p=0.10; MT-CO2, p=0.23; MT-CO3, p=0.07). Smoking tobacco or cannabis may not directly mutate these genes but may affect sperm through epigenetic mechanisms.
Conclusion: the reproductive effects of cannabis may be underestimated
The study concluded that both tobacco and cannabis reduce male fertility, with cannabis associated with deeper and potentially more persistent damage.
As cannabis legalization expands, public-health systems, policymakers, and individuals should consider its potential reproductive effects. The researchers called for greater public education, particularly for young men, about the long-term reproductive impact of tobacco and cannabis use.
News | Study suggests cannabis may harm male fertility more than cigarettes, raising concerns about a ‘hidden reproductive crisis’
News | Study suggests cannabis may harm male fertility more than cigarettes, raising concerns about a ‘hidden reproductive crisis’
A new study by Vijay Kumar Malesu and colleagues, published in Scientific Reports, found that both tobacco and cannabis have significant adverse effects on male fertility and sperm DNA integrity, with greater harm associated with cannabis.
Concerns about sperm health extend to the next generation
Male factors account for nearly half of infertility cases worldwide, while around 14% of couples face fertility difficulties and tobacco and recreational cannabis use continue to rise.
Tobacco smoke contains more than 7,000 chemicals, many known carcinogens and mutagens that directly damage sperm DNA. Tetrahydrocannabinol (THC), the active component of cannabis, can bind to receptors in sperm cells and significantly disrupt motility, viability, and morphology. Frequent cannabis use may also alter the sperm epigenome, potentially affecting offspring health.
Study design: comparison of three groups
Semen samples from 113 men were divided into nonsmokers (NS, 37), tobacco smokers (TS, 39), and cannabis smokers (CS, 37). Participants had no alcohol misuse, chronic disease, or genetic abnormalities.
Semen quality was assessed using World Health Organization (WHO) standards, including volume, sperm concentration, morphology, and motility. Fluorescent AO and CMA3 staining evaluated sperm DNA fragmentation and protein packaging, while PCR and Sanger sequencing examined variants in the mitochondrial genes MT-CO1, MT-CO2, and MT-CO3.
Key finding: sperm quality was poorest in the cannabis group
Results showed:
Normal morphology: 7.46% in nonsmokers, 5.02% in tobacco smokers, and 2.26% in cannabis smokers (p<0.001).
Non-progressive motility: 20.63% in the cannabis group, below 27.82% in the tobacco group and 34.40% in nonsmokers (p<0.001).
Immotile sperm: highest in the cannabis group (68.66%), followed by tobacco smokers (58.92%) and nonsmokers (51.73%) (p<0.001).
DNA fragmentation by AO staining: 28.53% in the cannabis group, compared with 6.4% in tobacco smokers and 10.1% in nonsmokers (p<0.001).
Protein-packaging defects by CMA3 staining: 37.13% in the cannabis group, compared with 25.3% in tobacco smokers and 15.0% in nonsmokers (p<0.001).
These measures indicate substantial structural and genetic sperm damage among cannabis users. Tobacco also harmed fertility, but cannabis was associated with more severe DNA damage and chromatin abnormalities, potentially affecting embryo development and pregnancy success.
Genetic analysis: no mutations identified, but epigenetic effects may exist
Researchers detected 23, 15, and 30 single-nucleotide polymorphisms (SNPs) in the three mitochondrial genes, but distribution did not differ significantly between groups (MT-CO1, p=0.10; MT-CO2, p=0.23; MT-CO3, p=0.07). Smoking tobacco or cannabis may not directly mutate these genes but may affect sperm through epigenetic mechanisms.
Conclusion: the reproductive effects of cannabis may be underestimated
The study concluded that both tobacco and cannabis reduce male fertility, with cannabis associated with deeper and potentially more persistent damage.
As cannabis legalization expands, public-health systems, policymakers, and individuals should consider its potential reproductive effects. The researchers called for greater public education, particularly for young men, about the long-term reproductive impact of tobacco and cannabis use.
Source:
Collected online