TGF-beta expression during rat pregnancy and activity on decidual cell survival.

Background: During early rat pregnancy, trophoblast of the tiny embryo joins with the endometrium and epithelial cells undergo apoptosis. Near the end of pregnancy, regression of the decidua basalis (DB) is also observed (from day 14 to 20). However, little is known about the intra-cellular and molecular mechanisms involved in apoptosis regulation in the uterus during pregnancy.