A baby?

I've wanted a baby for probably 3 years now. My SO already says he wants kids with me and to marry me. I'm glad but my education and work is holding me back. If I get pregnant I won't be able to do my job which is a part of my education. ( i am a mechanic and they would make me take an early maternity leave because all the toxins would harm the baby) Should I wait a couple more years? I'm just torn right now. Do I choose baby or Work/school? I'm not sure. Advice???