Many people have bumps on their outer arms and upper legs called keratosis pilaris:
littleLittle noses decongestant
Little tummys bumps of keratin protein in hair opening there. It's genetic but I think the pregnancy is coincidental. There are exfoliants you can use, and abrasives like loofahs and Buf Puf sponges. Only if the bums bother you are such maneuvers worth the effort. The bumps, being part of you, come back when they wish.
Of course, it's conceivable that you have some other kind of bumps; I'm just talking about the most
commonCommon cold kind. Next time you see a doc, ask.
Best.
Dr. Rockoff