You seem to have more knowledge of this sort of thing than I do — medicine is not my specialty — but I would have sworn that I saw this photo published with the caption “this was an ectopic pregnancy”. That has been 40 years ago and I may be conflating two different things.An ectopic pregnancy would never get to that point. Fallopian tubes don’t stretch, and they only accommodate the size of an ovum.
It could be a photo of a miscarried baby.
You say that fallopian tubes don’t stretch. If that is the case, how would there ever be a living conceived entity for anything longer than 5-6 weeks of pregnancy or thereabouts? Not to be crude, but if the fallopian tube stays the same size, wouldn’t the child be crushed and killed, and (obviously) cease to grow larger? The mother would have only known she was pregnant for a week or two. In other words, by the time medical complications would become evident, wouldn’t the child already be dead? And if so, how would using methotrexate be objectionable (aside from doing damage to the body of the entity)?