Question: What are the chances of pregnancy during menstruation?
The reason that it is unlikely to become pregnant during a woman’s menstrual period is because a pregnancy cannot occur if there is not an egg and some sperm to begin with.
Each month, most women release one egg – also called an ovum – during a process call ovulation. An egg typically lives for about 24 hours or less. Then, approximately 14 days after ovulation, a woman typically begins her menstrual period, meaning that she likely does not have any living eggs that have been released at that time.
Irregular or Short Cycles
At least not in theory. Sometimes women release more than one egg per month. More often, women’s cycles may be irregular or short. Also, sperm live longer than eggs do – some estimates suggest that sperm may live as long as 3 or 5 days. Some suggest that sperm may occasionally live in a woman’s body for as long as a week.
In any case, if a man ejaculates inside a woman’s vagina while she is on her period, and then she ovulates days later, or even a week later, it is possible that by the time she ovulates, sperm may still be alive in her body and able to fertilize her egg.
Likely? No. Possible? Yes.
Again, is it likely that a woman will become pregnant while she is menstruating? No. But is it possible? Absolutely. Our Kinsey Confidential web site provides more information about reliable forms of birth control to assist you in decisions related to family planning and safer sex.