Precum, also known as pre-ejaculate, is a clear fluid that is released from the male reproductive system prior to ejaculation. It serves several purposes, such as reducing acidity in the urethra, lubricating the passage for sperm, and potentially neutralizing any residual urine.

In terms of health, precum itself is not harmful. However, it can potentially contain sperm if there are residual sperm cells present in the urethra from a previous ejaculation. This means there is a risk, although relatively low, of pregnancy or sexually transmitted infections if precum comes into contact with the vagina or mucous membranes. Overall, it is important to practice safe sex to reduce these risks.