The fertile phase refers to the time during a woman's menstrual cycle when she is most likely to conceive. Some common synonyms for fertile phase include ovulation, fertile window, high fertility days, peak fertility days, and conception window. Other terms used to describe this phase may include the fertile period, the optimal time for conception, or the time of maximum fertility. It is important for couples who are trying to conceive to understand and track the woman's fertile phase in order to increase their chances of pregnancy. Using fertility awareness methods or ovulation predictor kits can help to identify this fertile window.