well a woman is only fertile a short while of the month, but when that magic moment happens, which is ovulation and not always predictable.... you can get pregnant. sperm can live in your body for days and if you had sex before ovulation or shortly after you can get pregnant....however if you period is always regular and arrives exact at the same time a day before your period you prob. could not get pregnant. BUT don't count on it, because this time the period might be delayed and then all you calculation is out the window....just be safe and use protection!!!
It depends...because healthy sperm can live in a women body for 3-5 days. More the likey you wouldn't get pregnany because you haven't ovulated yet. But really anything can happen.