Sexual Health

Knowing when you ovulate

1. Take the number of days in your usual cycle (from the beginning of one period to the beginning of the next). For example, most women have cycles that last 28 days.
2. Then subtract 14. So, 28-14=14. You would ovulate around day 14 in this case.

A woman with a 32 day cycle, would ovulate around day 18 (32-14=18). Because the sperm live longer than the egg does, (sperm live 48-72 hours after ejaculation), it’s best to have intercourse before ovulation rather than afterwards. Following our example, a woman who ovulates on day 14 would have a good chance of getting pregnant if she has intercourse on day 12, 13 or 14, and possibly even day 11.

For women with irregular cycles, one way to decide on the potential fertile period is by taking the shortest cycle and subtracting 16, then taking the longest cycle and subtracting 14. This would give the fertile time and allow for even more fluctuation in cycle length than usual. For example, the fertile period for a woman whose cycles vary from 27 to 33 days should be sometime between day 11 (27-16=11) and day 19 (33-12=21).

Women with irregular cycles may also want to consider using other methods to determine ovulation. Those other methods include looking for cervical mucus changes, measuring your basal body temperature, and using ovulation predictor kits.