I did after we had been together for a year. I knew I wanted to marry him before I even spoke to him. I found out I was pregnant at 18 and being that he wasn't going to run out on me (after I gave him every chance I could) I decided to pop the question with a custom made watch. He said yes but he still proposed twice more after that with two different rings (he first was too big) something about how he was making up for not asking first. We have now been together 8 years and will be getting married in September, finally. We now are both 24 with 2 boys who will be our ring bearers.
Throughout the years anytime someone brought up getting married I always said it wouldn't make sense for us for financial reasons. When it finally became legal a few years ago again a lot more people started asking. I would tell them "no baby no marriage". After 12 years of being together (and still no baby) I proposed! Shocked the crap out of her. She always thought she'd have to do it. I even called her parents beforehand and asked for their blessing. It was just after midnight New Year's day and in a very cheesy way but she loved it. I won't recant the whole story now since I've already written a book on this post.