This is a favorite question of everyone who is trying to get pregnant and a good question.
There are many signs and symptoms of pregnancy. I'll try to cover a lot of them here.
Missed Period
A missed period is probably one of the more reliable signs of pregnancy. Although some women will experience implantation bleeding about the time that their cycle is due, it is usually lighter and/or shorter than their normal period. This is why you are asked for the first day of your last normal period (LMP). There are even a few women who will continue to cycle throughout their pregnancy, although this is rare, it does happen.
If you've been planning for pregnancy, the day that you expect your period is probably well marked in your mind. It is the official day that you can take a home pregnancy test.
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Reference
http://pregnancy.about.com/od/amipre...I-Pregnant.htm
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