Masturbation: Self-stimulation of the genitals to achieve sexual arousal and pleasure, usually to the point of orgasm (sexual climax).
Melanoma: Cancer of the cells that produce pigment in the skin.
Metastasis: Cancer cells that break from a tumor and spread to other parts of the body.
Menstruation: The periodic shedding of a woman's uterine lining.
Menopause: When a woman's ovaries stop producing hormones because the number of eggs (follicles) is limited. At this time, regular menstrual periods stop.
Metronidazole: The most common medicine used to treat trichomoniasis. It is also used to treat bacterial vaginosis. A common brand name for this medicine is Flagyl.
Microsurgery: Surgery utilizing a microscope to enable doctors to operate on very small areas. Microsurgery is used to target a specific area and to protect as much of the surrounding healthy tissue as possible.
Mittelschmerz: The pelvic pain that some women experience during ovulation. (Ovulation generally occurs about mid way between menstrual cycles; hence the term mittelschmerz, which comes from the German words for "middle" and "pain.")
Monogamy: The practice of having sex with only one partner.
Neoplasm: An abnormal mass or colony of cells.
Nocturnal penile tumescence and rigidity testing: A test used to monitor erections that occur naturally during sleep. This test can help determine if a man's erectile problems are due to physical or psychological causes.
Non-coital behavior: Physically stimulating activity that does not include intercourse (such as sensual massage).
Non-infectious vaginitis: A form of vaginitis (irritation or inflammation of the vagina) that may result as a reaction to certain substances or chemicals, such as vaginal sprays, douches, spermicides, soap, laundry detergent, or fabric softener.
Non-seminoma: A type of testicular cancer that tends to be aggressive and occurs most often when men are in their 30s or younger. There are four types of non-seminomas: embryonal carcinomas, yolk sac tumors, teratomas, and choriocarcinomas. When these non-seminomas occur in combination, they are called mixed tumors.
Norplant: Six match-sized rubber capsules that are surgically implanted underneath the skin of a woman's upper arm. The sticks contain the hormone progestin, which releases slowly into the body and prevents pregnancy for up to five years. Norplant is no longer available in the U.S.