Pregnancy Possibility Before Period: Expert Advice

Question
i am 24 years old I have 4 Children my pre last menstral was not normal I had My period the 1 week in december and then again on dec 24 ( (starting date) my last period was January 19th 2005 i had unprotected sex with my husband on the 18th is it possible that I could get pregnant the night before my period started?

Answer
If you got your period, you are not pregnant. If your last period started on January 19, then you will not ovulate until February 1. You can only conceive if you have sex one day prior to ovulation or up to two days after ovulation. If the bleeding that you started on January 19 was not a normal period, and your last period really was December 24, you would have ovulated around January 6 and could have conceived if you had sex on January 5,6,7, or 8.  Once you get your period, you cannot be pregnant because the period is actually the sloughing off of the wall of the uterus (in which the baby is implanted).