A GUIDE TO FERTILITY

When in the month are women and men most fertile?

There is only a specific time in each menstrual cycle when it’s possible to get pregnant. This ‘fertile window’ is once a month, generally close to the time of ovulation when the woman ovulates and releases an egg approximately 2 weeks before the next period is due. Men do not have a ‘fertile window’ because sperm is continually formed and stored in the testicles, ready to be used at any time.

The days in the cycle with the highest chance of getting pregnant

Adapted from Colombo & Masarotto (2000). Daily fecundability: First results from a new database. Demographic Research. Retrieved from http://www.demographic-research.org/volumes/vol3/5/3-5.pdf

Graphic 1 shows when pregnancy is most likely to happen in people having sexual intercourse without contraception. Day ‘0’ is the day of ovulation when the egg is released. The pink section in graphic 1 shows that pregnancy is most likely to happen when sex takes place in the 3 days before ovulation. For example, the chance of pregnancy if people have sex -2 days before ovulation is 26% compared to 1% if they have sex +1 day after ovulation.

Because most women do not know on which day of the month they ovulate, contraception is recommended to avoid pregnancy.

There are ways to help predict ovulation but these methods are not a reliable from of contraception.

More Information