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I have probably read every post on here conserning blighted ovum and know that it can go either way. My last lmp was JAn 27/07 but I know I ovulated on day 26 by charting on a web site. By lmp I am due Nov3, but with O i guess 10 days later. Anyhow had bleeding on 3/17. ER said cervix was closed. U/S on 3/20 was told sac measured 6 wks but was empty, no fetal pole and no mention of a yolk sac. By lmp I was 7 wks 3 d, by O i was 6 wks. HAd HCG taken 3/21 the number was 24 529. Go tomorrow to find out 2nd set of numbers. Now with HCG like that shouldn't something have been seen? Is there hope that my O date could be off, and it was just too early, and how big is a 6 wk sac..I see alot of ##mm but don't know what the size of mine was. ANy info would be welcomed since I am going crazy with wonder and trying not to get false hope.