Immunomodulatory effects of progesterone and selective ligands of membrane progesterone receptors.

Progesterone (P4) and its analogues regulate various reproductive processes, such as ovulation, implantation, pregnancy maintenance and delivery. In these processes, an important role is played by the immune cells recruited to the female reproductive organs and tissues, where they are exposed to the action of P4. Progestins regulate cellular processes, acting through nuclear steroid receptors (nSRs), membrane P4 receptors (mPRs), and through the sensors.