R.C.
Hi M.,
Check the EPA website, I know they have some recommendations for safe treatment of fleas. The advantage should be fine, we used it on my cats, and only needed it for two years, before we didn't get fleas anymore. I'm just concerned about you applying it while you are pregnant. If I were you, I'd have my husband apply it, and then I wouldn't touch the dogs at all for several days, and then as little as possible during the flea season while they have it on them. Another thing we used when we didn't have bad fleas was garlic yeast tablets, and that helped when the fleas were light. But the advantage is good because it cures them from reproducing and infesting the environment. garlic yeast tablets just repel. A couple of other sources to check would be a naturopathic vet in Portland (there are several), and the website Healthy Child Healthy World.
Good luck!