[Frontiers in Bioscience 13, 1981-1990, January 1, 2008]

Role of progesterone and progestin therapy in threatened abortion and preterm labour

Julia Szekeres-Bartho1, Jacek R. Wilczynski2, Pawel Basta 3, Jaroslaw Kalinka4

1 Department of Medical Microbiology and Immunology,Medical School, Pecs University, H-7643 Pecs, Hungary, 2 Dept. of Gynecological Surgery, Polish Mother's Health Center Research Institute, Lodz, Poland, 3rd Chair and Dept. of Obstetrics and Gynecology, Medical University, Lodz, Poland, 3 Department of Gynecology, Obstetrics and Oncology of the Jagiellonian University, 23 Kopernika Str, 31- 501 Krakow, Poland, 4 Medical and Environmental Pregnancy Health Hazards Unit, Department of Perinatology, 1st Chair of Gynecology and Obstetrics, Medical University of Lodz, Poland, Wilenska 37, 94-029 Lodz, Poland


2. Introduction
3. The effects of progesterone during pregnancy
3.1. Endocrine effects of progesterone
3.2. Immunological effects of progesterone
4. Progesterone at early pregnancy and in threatened abortion
5. Progesterone in late pregnancy and preterm delivery
6. Summary and perspective
7. Acknowledgments
8. References


Progesterone (P) has been widely used in an attempt to prevent threatened miscarriage, recurrent miscarriage and pre-term labour. Successful pregnancy depends on maternal tolerance of the fetal "semi-allograft". Along with its endocrine effects, P also acts as an "immunosteroid", by controlling the bias towards a pregnancy protective immune milieu. A protein called progesterone-induced blocking factor (PIBF), by inducing a Th2 dominant cytokine production mediates the immunological effects of progesterone. Progesterone plays a role in uterine homing of NK cells and up-regulates HLA-G gene expression, the ligand for various NK inhibitory receptors. At high concentrations, progesterone is a potent inducer of Th2-type cytokines as well as of LIF and M-CSF production by T cells. The possible mechanisms by which progesterone contributes to the maintenance of early and late pregnancy are discussed.