The test is performed 1 to 2 days before ovulation, when estrogen-stimulated cervical mucus is abundant.
Basal body temperatures or the midcycle luteinizing hormone surge may be used to determine the timing of the PCT.
The presence of any forwardly motile sperm in alkaline mucus suggests adequate coital technique and a normal cervical mucus–sperm interaction.
[citation needed] The PCT is scheduled close to ovulation when mucus is abundant, and the infertile couple is asked to have sexual intercourse, preferably in early hours of morning.
[1] With the application of principles of evidence-based medicine the role of the PCT has been questioned and its use has become controversial.