If everything is going well in your relationship I wouldn't worry about it. I know that doesn't help very much but, guys aren't really into the whole marriage thing like women are. They just don't think about it. I wouldn't rush it or pressure him into it though, I would just be patient and when he feels the time is right, he will propose. If he has already told you that he could see himself marrying you one day then he has obviously put some thought into it somewhere. So just be patient and if he doesn't propose within a year or a year and a half, bring it up and tell him you want to have kids and you want to be married before you have children. You said you have already told him that though, so just be patient and see where things go.

It sounds as if you love him very much, as you are wanting to spend the rest of your life with him and have his children.

If you dwell on that whole "vasectomy" thing, you are going to drive yourself insane and potentially ruin your relationship. You and your man talk of marriage and kids all the time, you say. Two years really isn't that long to have not proposed. Perhaps he will do it when he is ready and comfortable? Obviously you are ready, and I'm guessing he knows this from the conversations you've had.

If you've talked about marriage positively, and you love each other, the only thing you can do is wait.

Why did he set the age of 36 as the magic vasectomy number?

He is comfortable. Nothing is going to change for him unless he is uncomfortable. Either patiently wait for what may or may not come or pursue your happiness elsewhere. There is a chance if you do the second, he will change his mind... then you must decide if that is who you want to marry, someone that has to be backed into a corner to make you happy.

Good luck