Experiences with retin-a

I have terrible, terrible cystic acne. For awhile I was sure I have pcos and my doctor says I don't..its been almost 5 years TTC. My dermatologist prescribed me retin-a cream for my acne & I have yet to use it because 1) im scared if I some day magically become pregnant (although it's unexplainably unlikely) I was told if I do fall pregnant to immediately stop and 2) I've been reading horror stories where it burns faces and makes their acne 20x worse even though at this point I'm not sure my painful acne could get any worse.....so has anyone taken this on a regular basis and had it actually work for acne? Any real life horror stories you can vouch for or would you recommend this?