Help!

Okay, so I am new to this. My husband and I are trying to conceive and I am trying to find out ways to make myself more fertile. My problem is that I have PCOS and my period is very irregular. My obgyn put me on progesterone to regulate my periods, however, I have read a couple of different things. I have read that progesterone is used as a fertility hormone and I have read that some people use it as birth control. Please give me tips and help me figure out what's going on.