Not sure if this will help, but I had the whole studying versus wanting a baby debate. I already had an undergraduate (done full-time) and a post-graduate degree (done part-time) and a good career when I decided to do a Masters degree, also part-time, only now my career was very demanding. I was 33 at the time and had felt broody for about 12 months but I was still in discussion with my hubby about starting a family as he needed longer think about it.
So, I started my Masters degree and wham! the studying part-time and working full-time hit me with full force. As I got through the 18 months the reading and assignments got more intense and so did my desire for a baby. I re-opened the debate with my hubby as I started to prepare for my dissertation. He said it was better to wait until after I'd finished my dissertation. Oh my God, how right he was! Researching my dissertation took all my time, efforts and emotional strength. I now know what it's like to feel pregnant and I was exhausted and felt sick. There's no way I could have completed my Masters feeling like that.
Whatever the studying is and whether you're doing it full-time or part-time, the decision to have a baby has to be a very personal one and it of course depends on your own situation. Do ask yourself though whether you will have the physical and emotional strength to do the two together. Also, if the pregnancy doesn't go smoothly, as mine didn't, will you be able to cope with studying too? All in all, I'm glad we waited, but that is just my experience. At the end of the day, nobody can take a qualification away from you and with some of them you only have one chance to do the exams/coursework and you may decide it's worth giving it 100% of your attention for a while.