No, definently not, I fell pregnant when neena was only 9 weeks old, still breast feeding but she had started sleeping through the night and had i not fallen pregnant, i would have gotten my period 2 weeks later. It was only cause i wasn't feeling well and she went off my breast milk (apparently it can taste different after you fall preggo or if you are menstruating) that i went to the doc, only to discover i was preggo! Unfortunatly, i had a misscarriage a few weeks later, but just be careful if you dont want to get pregnant, or have fun if you do!!!!!
Sare, DD1 1.03, DD2 4.06, DS edd 6.07