Hi Ladies, according to an IVF due date calculator I am either 5w1d (from LMP) or 5w3d (from retrieval). I had spotting today, slight, brown, so I went to the ER, they did my hcg which has risen from 2042 on wed, to 9498 today, however they were unable to see a sac on the u/s. They said it may be because it's too early. There was a black area but the doc said it was the Uterine Cavity, not the sac. Does anyone have any similar stories that ended well, or otherwise?