Hi Kazza. I initially thought my CD1 would be when I finally got down to zero HCG. However, looking at my charts now it appears that if I count the D&C as CD1, then O day would have been CD18 (making me now CD26). All I can think is that immediately after the D&C my HCG levels plummeted over a couple of days (to a point where I could start to O again), but that the last 200 mIU/L or so is tailing off really, really slowly. But I guess the proof will be when AF arrives. As to how it applies to a natural MC, I don't really know. All we can do is wait and see what happens! My fingers are crossed for both of us.