Hi there. Whew, you are sailing toward the end of your pregnancy. So, Nix lice treatment is pregnancy category B. That means it's not shown through studies to be harmful to the fetus but it also hasn't been studied much. So, in that situation people weight risks to benefits. I'd feel comfortable using Nix myself. You can run it by your doctor but think you are fine to have done so. Make sure you also do the whole combing to get the nits -- start at the scalp and comb through --- they make special combs for it or use a fine tooth. Those are . . . gulp . . . little eggs that could turn into active lice. You can also use tree tea oil on your scalp for control. Hope it got the job done . . . getting rid of lice is important. Wash your bedding and stuff too. Let us know how you are doing!