Men can carry a baby to term via embryo implantation and abdominal pregnancy.
This is so insanely dangerous (to both parent and fetus), that any physician who assisted in setting such a thing up would be in danger of having their license yanked. A number of healthy live births have been reported, but most often this special case of ectopic pregnancy ends up being surgically aborted -- because when allowed to proceed the likely scenario is massive hemorrhage followed by demise of the fetus (and maybe the parent too).
That being said, it makes for an interesting thought experiment. You'd probably want to select for a male embryo to implant, as the man's hormones will cause abnormal genitalia in a female infant. You might be able to alleviate this problem with testosterone suppression therapy (after all, females normally have a small amount of circulating testosterone naturally -- but it really doesn't take much excess to virilize a female fetus). What to do about other hormones is also an interesting question -- for instance, how necessary would it be to supplement progesterone, for instance?
Another important issue is the immunological tolerance that occurs in the female, we don't know if males will respond appropriately to with induction of the special partially-suppressed state that occurs during pregnancy. We also don't really know what all the hormones and other substances pumped out by the placenta and fetus would do to the male host.