The first thing that you need to do is educate yourself about ovulation and
the window of time which you can get pregnant. You should never have unprotected
sex, but the only time during which a woman get conceive is a day or two BEFORE
her period during ovulation when the egg leaves the fallopian tubes and is ripe
for fertillization into the extra thick lining of your uterus which sheds during
menstruation. But do not depend on time to be your method of birth control. The Rythm method, as it is know, is less than 55% effective, mostly because a woman's time of ovulation can change depending on a change of diet, exercise, or even life style. Use condoms or some other protection, but know that you can only conceive during ovulation.