2nd round of injectables

I have recently changed RE's and am currently doing my 2nd round of injectables to be followed with an IUI. I started clomid CD1-5 & on CD5 started 150 of follistim (overlap). I am to have blood work and an U/S on Tuesday. My first round back in April was clomid 150mg CD3-7 & on CD8 I started 150 of follistim with a micro dose of ovridel for 5 days. What was the purpose of the micro ovridel that was used during my first round? Does this injectable increase your chances of pregancy? I also have a problem with low estrogen--will starting the meds earlier in my cycle increase my E2 levels or should I ask for supplementation. In April I had a follicle 23, 18 & 15 and an E2 of less than 200. This will be my 3rd attempt at IUI---I was wondering how common and if a good practice to do back to back IUI's--1 using my DH sperm and then a sperm donor. My DH has some morphology issues.