Glossary

A lubricant in which the main ingredient is water. This is good for a latex condom because, unlike oil-based lubricants, water-based lubricants won't make or eat holes in it.

A man or a boy might have dreams about sex while he is sleeping. If he has an erection and then ejaculates this is a wet dream. It can happen to someone without that person knowing about it. Wet dreams are perfectly normal and can happen at any age. Wet dreams are sometimes called "nocturnal emissions."

One of the cells that are part of person's immune system. All fluids that transmit HIV have white blood cells in them.

Also known as "pulling out." During sex a male takes his penis out of another person's vagina, anus or mouth before ejaculation. This stops semen from getting inside the person. Withdrawal is not effective at preventing pregnancy or at preventing the spread of a std. A man's penis can leak pre-seminal fluid which contains sperm, into a woman's vagina, without knowing it. Pre-seminal fluids from a man, and vaginal fluids from a woman, can also spread stds before a man ejaculates.

Another word for uterus.