Many couples struggle with fertility – about 15 percent of couples in United States. Though infertility is often thought of as a woman’s issue, data suggests half of couples are affected by male infertility.

Infertility is defined as the inability to achieve pregnancy after a year of unprotected sex. Dr. David Samadi, the vice chairman of the Department of Urology at the Mount Sinai School of Medicine, wrote on the Fox News website that up to 50 percent of couples who have difficulty conceiving are affected by men’s health issues.

Often the culprit is sperm — either the size, shape, quantity or motility.

“One of the most common cause of male infertility is a varicocele, which is found in 40 percent of infertile men,” he wrote. “A varicocele is a group of dilated veins in the scrotom. For most men they don’t cause any issues and thus require no intervention. Some, however, can experience pain or impaired fertility.”

Chronic diseases like diabetes and liver cirrhosis also affects male fertility. Poor sugar management can cause damage to nerves that coordinate ejaculation. Liver cirrhosis causes hormonal imbalances that can interfere with sperm production.

A follicle-stimulating hormone (FSH) test is used to asses testicular function, while determining if the testes are able to produce sperm normally. This test can also detect poor mobility or potency of male sperm, which is commonly known to be a factor in infertility. Infertility issues in men bare no symptoms, so FSH testing is the only measure that confirms or eliminates the possibility of a man being infertile.

According to the National Library of Medicine, two-thirds of couples treated for infertility are still able to conceive.

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