The results of the blood panels are in, but the hematologist yesterday had his lab draw several more vials for additional testing and will call me with those results later. He wants to rule out any underlying pathology, but sees no cause for concern on that score yet.
The upshot is my iron stores and are low, not surprising, and I am supposed to stay on the nasty liquid iron. It appears that my bone marrow was beginning to respond to the increased available iron, even though the hemoglobin had dropped. It will probably take 6 weeks to verify if this therapy is working; if not, it's on to transfusions (I presume of packed red blood cells?).
Not being a doctor, I don't really understand all this, but the hematologist said it's a bit more complicated to transfuse blood during pregnancy as there are factors in the donor blood that might war with factors in the babies' respective blood. And we are dealing with five little people here. :) Therefore, he would prefer to avoid the transfusions (at which point I'd be in Dallas anyway with the perinatologist responsible for the rest of the pregnancy), but says my hemoglobin cannot go any lower. So that's a prayer request for those who are "battling the odds" with us throughout this pregnancy.