My wife and I are probably not the best example, but I thought I would throw in my two cents worth...
My wife and I were married when she got out of college (I'm about 5 years older) and she got pregnant on our wedding night (honestly, we abstained before marriage). After our oldest was born we tried a couple of solutions including Condoms and Diaphragm, but mostly condoms. Two years and three months after the first was born we went off birth control and she got pregnant within the month. The second was born 3yrs+1 day after the first.
After the standard 6-8 weeks, we went back on BC, just condoms for ease of use and then after another year and 3/4, we went off BC and then something strange happened, the Pregnancy test was positive and then she had a heavy wierd flow, the best bet is a *very* early spontaneous abortion. And then she got pregnant *again* a month later...
About six months after the third was born, we decided to call it quits with having kids. We'd talked about having 2 or 3 before we were married and she had more nausea with each successive pregnancy. After looking at the options, I decided that having a Vasectomy was our best option. Given that it only took me five days to recover, I count it as *much* better than having her have a Tubal ligation and besides, I got waited on hand and foot while I recovered.