I have wondered this myself, so I asked the nurse practicioner and she said that in research it hasnt shown any harmful affects on the baby, but it was still uncertain. I would definately not take bc pills if I thought I was preggo, just as a precausion.

No, it wouldn't hurt the baby/fetus if you were still taking birth control during the first few weeks of pregnancy. If you think you might be pregnant, the birth control pill will not have an effect on the accuracy of the home pregnancy test either.