"Pulling out before the man ejaculates, known as the withdrawal method, is not a foolproof method for birth control. Some ejaculate (fluid that contains sperm) may be released before the man actually climaxes. In addition, some men may not have the willpower or be able to withdraw in time."
"A woman normally produces a vaginal discharge that usually is described as clear or slightly cloudy, non-irritating, and odor-free. During the normal menstrual cycle, the amount and consistency of discharge can vary. At one time of the month, there may be a small amount of a very thin or watery discharge; and at another time, a more extensive thicker discharge may appear. All of these excretions could be considered normal. A vaginal discharge that has an odor or that is irritating usually is considered an abnormal discharge. The irritation might be itching or burning, or both. The itching may be…"
"Some STDs are there for life, like herpes and HIV. Others, like chlamydia and gonorrhea, can be treated, but you may get infected again if you have sexual contact with someone who has them. What can you do? Protect yourself with condoms, of course! And if you’re having sex, let your doctor know so you can get tested regularly. If you do get diagnosed with an STD, your partner should be treated at the same time you are. That way your partner will avoid future problems — and avoid reinfecting you"