follow-up question to "halachik definition of endometriosis" – #6401
I have another question
A lady showed me a blighted ovum that she aborted, it was slightly larger than a chicken's egg, and I would like to know:
1. how do doctors ascertain that no fetus developed whilst it is still in the womb?
2. If a sonogram is used, is there any room for an error?
3. Does it depend on the age of the ovum?
4. Once aborted do doctors recheck the ovum?
If it is dissected what noticeable difference is there from a fertilized ovum?