Hi, Thanks for the query. GestofitSR is a progesterone tablet. Progesterone helps in maintaining uterine quiescence. Fibroids can grow during pregnancy under the influence of hormones. This can lead to complications like red degeneration, abortions etc. For more details : http://srsree.blogspot.in/2013/11/fibroids-part-3 . html So, to prevent premature uterine action due to the fibroids, progesterone can be used prophylactically. You can follow your doctor s advice as here benefits overweigh the risks. Take care.