I started my MBA when my dd1 was 9 months old. At the time I was working half-time over 3 days. The MBA lectures and tutorials were two evenings per week, and assessment was a mixture of exam based and assignment based.
When dd was 18 months I moved to a new job which was full time.
At times I felt myself to be under huge pressure, and even now, many years later, I remember sitting up at 1 or 2 am writing essays / assignments - but then last minute work was always part of my habits! On occasions I felt overwhelmed by it all, but when I did I promised myself that if I felt the same a week later, then I'd give something up. And at least I felt I had options to either defer my course, or to reduce my work hours. And I always found that a couple of days after the overwhelm crisis I was feeling back in control and more on top of things.
For me personally it was the best thing I ever did (even though I paid my fees myself). It brought me into contact with a whole new group of people, it made my brain work really hard, and it did wonders for my self-esteem.
It also taught me the best ever skills in time-management. Because it was a part-time MBA all the students were working. In the first term I think we tried to approach it like full-time students, to go to the library, read a lot around the subject etc. By the end of the 3rd year we were all massively more efficient at knowing which bits of information were essential, what was interesting (but not essential), and what was just a distraction. That is a skill which has been more useful to me than any other part of the course.
And I had the most wonderful social life 
It helped that I was not (and am not) a perfectionist. I think if you needed to be the perfect Mum, the perfect employee/boss/co-worker, and the perfect student, then you would drive yourself nuts. I trusted my dh to look after dc on the evenings when I was out, I stopped working ridiculous hours at work, and I let go of my need to be the star pupil in the class (but still driven enough to get good grades). I also think that because I was out a couple of nights a week, dh had to become a very hands-on-dad - useful when we spilt up seven years later.