No an embryo cannot fall out by those things. Sperm swim and so can move. Blood is a fluid and can move. The embryo is placed into the endometrium and then it cannot move. Now the endometrium can move if it breaks down ie like blood from menstrual cycle but the embryo once it is placed just sits in the endometrium and has no where to go. It can implant or fail to implant and then you get your period.
I agree with your doctor. It would not affect the transfer.
Thank you for your help. ANother question if you have time- is there any way an embryo can "fall out" by coughing, laughing, bowel movement strains, etc? I know they say it is impossible but I am still worried. If sperm can get in and blood can get out (period) why can't a microscopic embryo come out?
THANK YOU!!!!