The more I've thought about it, the more I've become worried about the possibility of releasing five eggs on Saturday. More targets provide more opportunities. . . but I also don't want to get pregnant with quintuplets! MM's sperm count is higher-than-average, so who knows? Maybe all of the eggs would fertilize and implant!
So I called my RE's office for some information and reassurance. My RE’s nurse called me back and told me that my three smaller follicles (all on the right ovary) measured 10 mm, 10 mm, and 11 mm yesterday. These follicles would not be expected to be mature and release an egg after I trigger tomorrow night. My other two follicles (on the left) were 20 mm and 16 mm. The 20 mm follicle will almost certainly produce an egg and, using an average 2 mm/day growth rate, there is a chance that the 16 mm follicle will mature to that point by Saturday morning also. She said that with Clomid, they expect the follicle to be at least 21 mm in order to release a mature egg.
So it sounds like they are predicting one to two eggs being released, which sounds perfect. The nurse said that this isn’t definite--she actually said "I don't have a crystal ball"--but that it would be unusual for the three smaller follicles to “catch up” enough to actually release mature eggs by Saturday morning.
I was reassured by this. It seems that the odds of my even having more than two eggs at the time of the IUI are quite slim. When I couple that with the odds of any of them actually resulting in a pregnancy, I feel pretty safe that I won't be seeing five heartbeats on a future u/s.