However, using a conception calculator
and working back from the due date she gave you of October 24th, the first day of her last period would come up at around the 17th of January. So something does not match -- did she get the October 24th estimate from her doctor based on an ultrasound of the embryo, or did she just compute it herself? If she computed it herself, would she have any reason to push the supposed date of conception back a couple of weeks? (I.e.