Turns out that friends of ours are also doing IVF, and are about 1.5 weeks behind us. We had gotten together for dinner while the women were taking their pre-procedure medications, and there was lots of comeraderie. Still, with our odds of success being ~40%, and theirs being ~25% (she's a couple of years older than Kathy), I later mentioned to Kathy that the odds weren't good that both couples would get pregnant -- in fact, the odds were 45% that neither couple would get pregnant, 45% that one would, and just 10% that both succeed. I pointed this out to Kathy because of the realization that there could be a strain on the friendship if one couple was successful and the other wasn't.
Today we found out that they are also pregnant, so the 1 in 10 chance happened. Hurray!