welcome to hcm
thanks for the query
as you mentioned above, it appears to be anembryonic gestation or blighted ovum
.in this case in usg the gestation sac will appear normal but the embryo never develops as the pregnancy
generally embryo will be detected by usg by 6 week after lmp.
so you discuss with your doctor what to do next.he will suggest you the best method to terminate it i.e medical method or surgical procedure.
but dont worry. in most of the women ,the problem of blighted ovum occurs only once
try to find out the cause by consulting your doctor.this can make your next pregnancy smooth.
chromosomal problems can cause the problem.
wishing you good health