How to tell the father

How do you tell the father, that you are pregnant? Not really knowing how they will take it, or even how well they will take it. I mean I know that some say that they know as soon as it happens but is that really true? My daughter's father never knew until I told him and then I just couldn't stand him afterwards. But this one I think that he already knows and if he doesn't know I think that he is really trying to get one from me. So how do you tell him that he has made an accomplishment and now it is time to hold on to his end?