Chronic cannabidiol exposure promotes functional impairment in sexual behavior and fertility of male mice

•CBD has biphasic effects on male copulation.•CBD negatively affected the fertilization rate and the number of litters.•The antifertility properties indicate that CBD can act on the sperm acrosome reaction. Cannabidiol (CBD) is a potent substance extracted from Cannabis sativa. As it has been suggested that marijuana can affect the reproductive system, we decided to assess the effects of chronic CBD exposure on the male reproductive system in an animal model. 21-day old male Swiss mice received CBD for 34 consecutive days at doses (p.o.) of either 15 or 30 mg/kg, and a control group received sunflower oil. Body weight gain and circulating progesterone concentration did not significantly change in CBD-treated animals. In the sexual behavior analysis, the CBD 15 group presented a delay in performing the first mount and intromission, and a reduced number of mounts and ejaculations. The CBD 30 group showed a 30% reduction in fertility rate and a 23% reduction in the number of litters. Our results indicate that chronic CBD exposure promotes functional impairment of the reproductive system of male Swiss mice.