I don't believe folate would help, so but would have to investigate it further to say confidently. Since I'm home with the flu right now, I don't want to participate in anything that has me thinking too hard! Folate is most helpful for neuro developement, and as such, is mostly beneficial in the first few weeks of pregnancy, so women who start the folate/prenatal vitamins when they find out they are pregnant, have already missed the most critical part of their childs development when the folate would have helped. I see that a lot sadly, so I try to tell patients to take it anytime you're not on BC pills. I'm sure you know a lot of that since I see you're "Elbow deep in a cadaver...". (If you have to cut the cadaver into two late in anatomy class, volunteer to saw, not hold the cadaver... holding is the messy job and avoid hitting the colon!! have someone hold it to the side!)
Methotrexate if I recall from my pharmacology class days can cause cell division to be impaired and therefore can terminate a pregnancy, but it's never been labeled for such use that I know of. It was studied for such use, but again, not approved. Has it been used for abortions? Probably, but it's way off label. It's a terrible drug to use in a pregnant woman, especially early in the pregnancy as it can terminate the pregnancy easily. I don't recall the article saying how far along she was at the time of taking the methotrexate. If it was taken late in the pregnancy it would be a much better situation, less risk.
-Brad