My last RE thought it was fine, I went with her advice, but my results were so bad that I almost had nothing to transfer on day 3.
But I think it is common sense that in each cycle we are pumping such an unnatural amount of hormones into the body, and back to back means our ovaries get no rest at all. Dr. Zouves, a doctor in the Bay Area who is known for his very aggressive approach (in terms of dosage and gimmicks), told me that he would never put a patient through hyperstimulation without 8 weeks of rest in between.
The manifestation of back to back on me was both empty follicles (5 out of 10 on one count) and extremely fast growth on the lead follicle. I had to trigger only after 5 full days of stim. If I were you, I would definitely rest a couple of months before attempting another stimulated cycle.
I am on low stim for 3 months so far and I have never had one empty follicle.