Ovulation Calendar


Increase your chance of getting pregnant by determining your most important fertile days. Menstrual periods vary from woman to woman and month to month. If you’re trying to fall pregnant, the timing of when you and your partner have intercourse is critical. The best time to try and conceive is during the ‘fertile window’ of the menstrual cycle. Fertile Window refers to the five days before ovulation through to the day of ovulation. These six days are the ‘fertile window’ in a woman’s cycle, and reflect the lifespan of sperm (5 days) and the lifespan of the ovum (24 hours). Pregnancy is technically only possible during the fertile window.

If a woman has intercourse six or more days before she ovulates, the chance she will get pregnant is virtually zero. If she has intercourse five days before she ovulates, her probability of pregnancy is about 10%.

The probability of pregnancy rises steadily until the two days before and including the day of ovulation.

At the end of the ‘fertile window’, the probability of pregnancy declines rapidly and by 12-24 hours after she ovulates, a woman is no longer able to get pregnant during that cycle.
This calculator helps you predict your most fertile days of the month. Use this ovulation calculator to help determine your fertility window.