Cytoplasmic male sterility is total or partial male sterility in plants as the result of specific nuclear and mitochondrial interactions. Male sterility is the failure of plants to produce functional anthers, pollen, or male gametes.
Among the factors that can cause male infertility are semen disorders, systemic disease, genital infection, genetic defects, and drugs. Also cocktails of pesticides and other chemicals in the environment are believed to be affecting male foetuses by blocking testosterone in the womb or imitating oestrogen, so disrupting male sexual development and function.
Over the same period of decreasing male fertility there has been a growth in testicular cancer and other genital abnormalities such as cryptorchidism (undescended testicles in children) and hypospadias. Testicular cancer is correlated with severely depressed semen quality.
Such remarkable changes in semen quality and the occurrence of genitourinary abnormalities may have a common cause.