you could always say you forgot to take it and then let him know that you were thinking of having another baby anyway and what does he think? within the first 5 minutes of that conversation you will know yes or no to a new baby

Wow, that's really an awful thing to do! Marriage is supposed to be a partnership. It is also supposed to be based on trust. Tricking him into having another baby is the wrong way to get what you want. I agree with one of the previous posts, how would you feel if he tricked you into getting pregnant if you didn't want another child?? My ex husband told me he was sterile when we met, right after I told him I wanted to concentrate on finishing college and not have children until we were financially secure and I could stay at home at least part time. Needless to say I ended up pregnant VERY QUICKLY and as it turns out my oldest has severe disabilities. Now, I'm glad I have my kids and I wouldn't go back and change anything because I'm grateful to have them but it really changed the course of my life. It's a good thing I was up to the challenge, I could have been resentful and taken it out of my first born, maybe even decided to put her in an institution, gotten a divorce and not ever known my second child at all. That is a scenario I can't even imagine but if I hadn't been willing to deal with the situation it's what could have happened. AND that lie was a major reason our marriage did not work. Well . . . that and the fact that he was a - can we cuss on these boards??
So tell him, now. Discuss this like two married people. And if you can't you should look at why not. Above all, I wish you the best of luck with whatever happens, it sounds like you are going to need it.

Oh my goodness. This is a Life Interrupted moment! Stop what you're doing, and tell him the truth. Give him ALL the information so he can make an informed decision. That is the respectful thing to do in a marriage. Your husbamd deserves that from you.

Tricking him into that third child is not a good idea. You are going to damage your whole relationship in the process of getting something you think you want. You need to tell the man you love the truth it is hard enough raising children with someone you trust if you make it so he cannot trust you it will only get harder.