How/when do I explain dropping out of Uni when applying for apprenticeships?

Hi, first post. Will try to be brief!

So I got some excellent A-Level grades and went to QMUL to study Law in 2011. Everything was going well in all aspects until the following Jan.

Long story short, I had a medical condition that hit me hard, I fell behind and gave up a bit if I'm honest. Thought about leaving but wanted to see year through and tried to claw it back. Did my first of 4 exams, went okay considering and got 59%. But I found out I was pregnant (when doctors told me my condition had affected my fertility) literally the DAY before I started my 3 exams in 4 days. And I just lost it, I was totally shocked, had no focus and ended up failing them all by getting 39%.

Then I found out it was twins whilst considering my options. I completely gave up and went and withdrew from Uni that day (even the course coordinator told me i was doing the right thing)! Now I've had (extended) "maternity leave" I'm looking for a full time career move.

I dont wish to return to Uni as I'd rather not get into any more debt with two little ones to think of. Priorities are working and earning, but I still want to get a professional qualification because I have the ability and dont want to waste it!

question is now;
I want to do some sort of legal apprenticeship (got a few various ones lined up) but I dont know how to explain dropping out. Its awkward because;

a) its an apprenticeship intended as an alternative to Uni, when I've already been. But if a legal apprenticeship had existed then like it does now I defo wouldnt have gone to Uni (i looked but found nothing!). How do i explain myself so it doesnt sound like im doing this as a backup because i failed?

b)its a LEGAL apprenticeship. So they will want to know ALL the details. As in I failed the exams but still think im cut out to be a lawyer, or is this being too harsh on myself considering how I felt at the time? Will they even let me do one when I have attended a years Uni? I didnt get a Certificate of HE or anything, obviously. Would they check with QM when exactly I withdrew? Cos I've thought about saying I left and got "no result" rather than mentioning a failure on my CV or application before I can properly explain myself.

Do I mention anything more than the fact that I went for a year and withdrew? When they ask Q's like Why is this a more attractive prospect than Uni i just dont know how to explain myself succinctly (as you can see!!) and positively.

Any help would be great! Please?! Thanks!