I mean hell, I think she'd take up with one of her superhero friends before she started dating someone and leading him on.
I'd think so too, but who's available? It would be inappropriate in several jillion ways to ask Clark. Bruce has enough issues about fatherhood already. J'onn? Actually, I can kind of see that, and it's probably possible, since every vaguely humanoid species in the DCU can apparently have kids together no trouble.
Of course, if she really wants to get pregnant immediately with no uncertainty about it at all, she should tap one of the male Arrows. Assuming Ollie is out of the question (a, married, and b, ahahaha yeah right) it's a toss-up between the semi-virginal Buddhist who's kind of scared of women, and Diana's little sister's sloppy seconds. Maybe Connor would be best; Lian would be hella jealous of her little half-sister getting to be an Amazon princess.