the Patch; Ortho Evra: Hormonal method of birth control applied directly to a woman’s skin via an adhesive patch.

pedophile: A person who wants to have sex with children and young adults.

pelvic inflammatory disease; PID: A genital infection in a woman that has spread into the deeper organs of her reproductive system, including the uterus, fallopian tubes, or the structures around the ovaries; not technically an STD but may be a consequence of an STD, usually either gonorrhea or chlamydia; can lead to serious consequences if not treated in time.

perimenopause: Period of life preceding menopause, experienced when a woman’s ovaries become resistant to follicle stimulating hormone (FSH) and the body reacts with a spike in estrogen; usually lasts about four years but may last anywhere from a few months to 15 years.

perineum: The area between the genital organ and the anus.

Peyronie’s disease: Medical condition in which the erect penis curves or bends sharply to one side such that sex may be impossible.

the Pill: Hormonal method of birth control taken orally, available under many names.

premonitory sensation: The feeling that a man gets just before he reaches the point of no return before orgasm/ejaculation, also called "the moment of inevitability."

priapism: Medical condition in which a man suffers from a permanent erection.

progesterone: A female hormone; plays a key role in triggering the process needed to create a baby; no longer produced after menopause.

prostate gland; prostate: The prostate gland, located below the man’s bladder, produces some of the fluids that are contained in the semen, giving semen its whitish color.

psychogenic erection: An erection caused by an external, non-immediate stimulus that trigger the brain to release hormones that cause an erection.

pubic lice; crabs: Lice that live in the pubic area, and whose bites cause intense itching; visible to the naked eye; treatable with over-the-counter medication.

pubococcygeus muscles; PC muscles: The set of muscles in the genital area that incurs the most contractions during orgasm; found in both men and women.