How you prepare

By Mayo Clinic Staff

You might need to have a full bladder for chorionic villus sampling, so drink plenty of fluids before your appointment. Depending on the position of the placenta, however, you might be asked to empty your bladder just before the procedure.

Your health care provider might ask you to sign a consent form before the procedure begins. Consider asking someone to accompany you to the appointment for emotional support or to drive you home afterward.

Oct. 10, 2012