But how much would it even be her own kid? When Q proposed breeding to Janeway she thought it was the traditional method but then she got to witness the event with Lady Q. I doubt Lady Q swelled with child. Instant conception with a touch, instant infant materializes, instant teenager appears before you. ALL the fun parts skipped. Vash's ability to have any input would have been very limited.. and if the teenager that she conceived 5 minutes ago didn't want anything to do with her it's not like they went through a whole childhood of raising that she could hope would tug at teen-Q's heartstrings. And if teen-Q did want her to be in his life 24/7 it's not like she could get rid of him.
It's really an egg donation with the possibility that the result might take over your life.