Your chances of getting pregnant on your period are considered to be lower than if you weren't menstuating, however, it is definately possible. I know quite a few women this happened to.
I've done some research and came up with this:
Sperm can live inside you for 5 days. You could have sex near the end of your period and the sperm could then live long enough to fertilize an egg several days later if you had a very early ovulation. If you have unprotected sex, you are at risk of becoming pregnant at any time during the month, period or not. Women ovulate at different times, depending on the length of your period cycle. The most fertile time to get pregnant is usually 3 days before and 3 days after ovulation. Generally, it is not likely to get pregnant on your period, but it is definately possible.
I would wait unti the time youre expecting your next period and see if it comes. If not, take a home pregnancy test and see what happens. I wish I could say you are not pregnant, but noone knows but your body right now. There are pregnancy tests in which you can test upto 5 days before youre expecting your period, so maybe take one now and see what it says since you say its been 3 weeks. You should be expecting your period soon anyways. Pregnancy tests are highly sensitive now a days, so take a test now. It will most likely give an accurate result.
Brandi_S answered Wednesday September 10 2008, 1:45 pm: Anytime you have unprotected sex, you put yourself at that risk. Yes, you can get pregnant while on your period.
Also, not using condoms puts you at risk of getting and passing STDs.
I strongly suggest you research facts and myths regarding pregnancy and STDs. An informed girl is a wise girl.
rainbowcherrie answered Wednesday September 10 2008, 1:42 pm: It doesn't matter if you've been lucky before, whenever you have sex without contraception there is a risk of you becoming pregnant. Just because you were on your period does not mean you won't get pregnant, you can get pregnant at any time of the month but sometimes your chances will be higher or lower.
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