A traditional method of natural family planning. The fertile phase of the menstrual cycle is determined by calculating the length of at least six previous menstrual cycles. The beginning of the fertile phase is determined by subtracting 18 to 20 from the length of the shortest menstrual cycle. The end of the fertile phase is determined by subtracting 10 or 11 from the longest menstrual cycle. When used alone, the calendar method may be unreliable, especially for women with irregular menstrual cycles, and may be overly restrictive for some couples.

The process of preparing sperm by artificial means so that their chances of fertilizing an egg are enhanced.

Pockets in the cervical canal that contain mucus-producing cells and store sperm.

A fluid of varying consistency produced by the cells in the cervical crypts. The secretion of cervical mucus is controlled by estrogen and progesterone.

The tube-like lowermost portion of the uterus that opens into the vagina. "Cervicitis" refers to inflammation of the cervix.

A positive pregnancy test as determined by the presence of hCG in blood or urine. HCG is the hormone produced by the embryo, but its presence does not guarantee that the pregnancy will continue to a stage of viability.

A kind of bacteria that is responsible for infections of the genital tract, especially through sexual transmission.

A fertility drug (marketed as Clomid or Serophene) that stimulates ovulation.

A pregnancy that has reached the point at which the fetus has a detectable heartbeat as determined by ultrasound.