Exhibiting no symptoms.

The complete absence of sperm in the ejaculate.

Single-celled living organisms, some of which can trigger infections in the reproductive system.

The lowest body temperature during the day (usually early morning). For a woman, the BBT has a pattern of being lower than normal prior to ovulation and higher than normal after ovulation.

A small sample of body tissue removed for microscopic examination.

A recent advance in infertility treatment, in which embryos develop for 4 or 5 days (until they reach blastocyst stage), rather than the usual 2 or 3 days in IVF.

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.