HCG injections after IUI?

Candace
I'm preparing for my 4th and final IUI which will probably occur at the end of next week. I don't know what took so long but I recently discovered I have a short luteal phase. I spoke with my RE and expected that maybe we'd try progesterone supplementation after the IUI. Instead she wants to do HCG injections. Anyone else done this?? What was your outcome?