I don't know what it is, but my uterus is such a drama queen. Last time around, I had a bleeding episode at around 8 weeks that foreshadowed the loss of a twin. Last night (at 8 weeks, 1 day), I woke up for my usual 2 a.m. pee to find a pantiliner soaked with red blood. Which, of course, incited total panic.
Our RE was able to see us at 9:30 this morning, and thank God everything looks great. The nugget is measuring a little big, with a heartbeat chugging along at 167 BPM. The doctor said that the bleeding is very common -- he sees it in 50% (!) of IVF pregnancies, and it's almost always benign -- and that I shouldn't worry as long as it tapers off. Easy for him to say, but comforting (I guess) nonetheless. There was no sign of any clots or other scary things in there, which is apparently also good.
So, we have a another scan on Tuesday, and then I'll graduate to the regular OB. (Of which I need to find another, since mine retired.) This is all going by really fast....and really slow....at the same time. Yikes!