My dr did a papsmear because I'm four months pregnant and 1 out of thirty was abnormal and they say I need to take my husband to be checked why isthat?

They're checking for HPV or other infections that could cause an abnormal result. I believe they're just trying to be thorough in their diagnosis of the abnormal culture.

HPV is a known culprit of cervical cancer. This is why they're reacting quickly, they want to make sure that baby, yourself, and your husband will be all healthy.