Simply put after much searching on here I've found little to none of this so here i have a few ideas for anyone who might want to make a story about it. Firstly the way i see it a pregnant male would have to deal with all the changes a woman would normally so that would include hormones, breast growth ect... But there would also be growing pressure against the prostate as the pregnancy progresses. On a related idea perhaps explore how a schoolboy would have to deal with this "knowing" boys can't get pregnant.