Missed miscarriage?

Patient: My ob/gyn has told me I have a blighted ovum. I have what looks like a healthy yolk sac and gestational sac. Up until yesterday I had what he called a fetal pole. Yesterday he told me what he sees measures at 7 weeks, but he does not see a fetal pole anymore and could not find a heartbeat. He suggested that I come in and have an induced miscarriage. I should be 9 weeks according to my lmp, but my measurements have been wrong. I have had three scans in the past four weeks that looks like things are progressing, but he still cannot find a heartbeat and says I have not progressed enough from the first scan. I’m wondering if I should wait another two weeks and see if things happen naturally if something is wrong, then if nothing happens go ahead and get another scan? Or is everything correct based on what he is seeing in the scans. I know dates can be wrong, but I don’t want to make the wrong decision either way, and I definitely don’t want to abort if there is a chance the baby is in there and maybe just hiding. Te scan that you can’t see the date on that I am uploading was done 2-10-14. The first 2 the dates show. The first was 1-20-14 and the second was 2-3-14.