What are the chances of getting pregnant if I have sex during my period?

In order to get pregnant, a sperm must meet and fertilize an egg, so any factors that affect this also affect your fertility. These include: the timing of ovulation, how long the egg lasts, whether there are any sperm present and how long sperm can live inside you.

Women who have regular periods can easily calculate when ovulation occurs. Ovulation almost always happens 14 days before you expect your period. For a woman who has 28 day cycles, that would be in the exact middle of the cycle, 14 days after the last period and 14 days before the next one. Women who have 30 day cycles can expect to ovulate 16 days after the last period, which is 14 days before the next one. Since most women have periods that last from 4-7 days, the chances of getting pregnant during your period are very low.

There is an important exception to this, however. Women who have irregular cycles cannot predict when they will ovulate. Furthermore, many women who have irregular periods also have episodes of irregular bleeding that are not periods, even though they look like periods. If you have sex during an episode of irregular bleeding, you might ovulate soon thereafter, and therefore you could get pregnant.