For many couples facing infertility, medicine offers a range of solutions. But for men with non-obstructive azoospermia (NOA)—a genetic condition where sperm production stalls—options remain limited.

Sperm are male reproductive (sex) cells. The word “sperm” can refer to spermatozoon (singular) or spermatozoa (plural). Sperm are tiny cells with an oval-shaped body and a long tail. They measure just ...

For decades, sperm were thought to become fully active the moment they entered the female reproductive tract. New research suggests otherwise. A temperature-sensitive switch inside sperm cells may ...