Ovulation test

Fertility testing is the process by which fertility is assessed, both generally and also to find the fertile window. General health affects fertility, and STI testing is an important related field.

Healthy women are fertile from puberty until menopause, although fertility is typically much reduced towards the extremes of this period. The onset of puberty is typically identified by menarche and the presence of secondary sexual characteristics such as breast development, the appearance of pubic hair and changes to body fat distribution. The end of a woman's fertile years typically comes somewhat before menopause, as fertility declines to a point where establishing a viable pregnancy is very unlikely.

Various methods of predicting fertility exist, to either aid or avoid pregnancy.

Cervical mucus becomes clear and stretchy during the fertile window, to allow sperm to survive in and travel through it. The consistency of fertile mucous is akin to egg white.

Ovulation prediction kits are usually antibody tests for luteinising hormone, which peaks in urine around the time of ovulation. More sophisticated tests, such as the Clearblue fertility monitor, also test for estradiol.

The cervix becomes soft, high, open and wet during the fertile window.

Basal body temperature changes during the menstrual cycle. Higher levels of progesterone released during the menstrual cycle causes an abrupt increase in basal body temperature by 0.5 °C to 1 °C at the time of ovulation. This enables identification of the fertile window through the use of commercial thermometers. This test can also indicate if there are issues with ovulation.

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