Allen TK, Feng L, Nazzal M, Grotegut CA, Buhimschi IA, Murtha AP. The Effect of Progestins on Tumor Necrosis Factor a-Induced Matrix Metalloproteinase-9 Activity and Gene Expression in Human Primary Amnion and Chorion Cells In Vitro. Anesth Analg. 2015 May; 120(5):1085-94.