Ash, the success rate is higher with injectables, so I'd give that a go. More eggs, and better quality.
Dilia - it's such a personal decision. From what I've read, increasing the dose does not recruit MORE eggs, it just makes them develop faster. So increasing the dosage of a med is not always the right thing. But perhaps a different medication all together? Why Bravelle and not Follistim/Gonal F? Curious.
We were just confronted with the same decision (move forward with another 1-2 IUIs or go to IVF). Our decision was largely based on our insurance situation (limited funds for ART), but our doctor did say that if IUI is going to work, it usually works the first few tries. He said that if it works, it's because it's addressing a subtle ovulation problem that's corrected with the meds, a timing problem, a mild sperm problem, or a hostile CM problem. After try number 3 or 4, the chance for success with IUI is much lower, because if it's not working, there are likely OTHER problems that may need to be corrected with IVF. That's not to say it never happens of course - there are definitely women who get pregnant on their 7th IUI or get pregnant naturally after IVF. It's just that if you are going this route with ART, and want this to happen in a time and cost efficient way, doing more than 3-4 tries isn't advisable. According to my doctor anyway.