After sex how long does a woman take to get pregnant?

, It is almost 4 weeks from the first day of your last period to the to the next time of your Possiable missed period, This is the first sign that you may be pregnant, ON average a women’s cycle is 28 days, NOW mine is about 30 days. Give or take So I got my period on 2-1-09, I Would ovulate on or around the 14-17th of Feb. I had sex on 2-15-09. I MISSED my period on 3-1-09, SO I took a test on 3-5-09. It was postive. AS far as how long it takes after sex, well It could be right away if a egg is already present, it could be 12 hrs later when a egg drops. Sperm can live for several days in a womens body, however with each passing day your chances decrease because the sperm “get lost” sort of speak. AGAIN this get tricky, because once you find out that you are pregnant. The doctors start your pregnancy from the first day of your last period, SO even thought I knew it happened 2-15-09. The doctors started my pregnancy at 2-1-09, the first day of my last period. So by the time you find out you are pregnant you are already around 4 weeks. I did not get sick until around 8 weeks. This ultra sound is at my 7 1/2 week gestation. I am due 11-8-09