I had sex 4 days after a cervical biopsy and now am bleeding again , what to do if there's an infection?

See your MD: We usually ask patents to abstain from sex after a biopsy as the biopsy site is "raw' and can easily re-bleed if disturbed. Your md can sometimes stop the bleeding by placing a temporary "patch" using silver nitrate or monsel's solution- so give him/her a call.

Antibiotics: Talk with your gynecologist. She will need to examine you and then discuss antibiotics. You don't want an infection or std to become invasive and cause complications.