Welcome to healthcaremagic.
Your doctor must have good reasons why he prescribed the medication so I suggest you take the betnasol 12mg as prescribed. Did your doctor explain to you the reason for the betnasol? Probably for fetal lung maturation since you are having a cervical polyp
( which is a pregnancy
risk factor for premature labor
). Just complete the treatment or give him/her a call to find out the actual indication of the betnasol 12mg.
Hope this helps