Oh, the twisted love story of progesterone and pre-term birth! Ever since the Meis trial in 2003, we have been fascinated with the use of progesterone as a possible cure-all of all things preterm birth. But the data keeps piling in, with results just contrary to that. In this episode we will review the publication history of progesterone and it’s fight against PTB. We will also highlight a new publication from the AJOG coming out September 1, 2022 analyzing vaginal progesterone’s effectiveness against PTB. Does it work? Let’s find out.