Modulation of the endocannabinoid system in viable and non-viable first trimester pregnancies by pregnancy-related hormones.

Background: In early pregnancy, increased plasma levels of the endocannabinoid anandamide (AEA) are associated with miscarriage through mechanisms that might affect the developing placenta or maternal decidua.

Methods: In this study, we compare AEA levels in failed and viable pregnancies with the levels of the trophoblastic hormones (beta-human chorionic gonadotrophin (beta-hCG), progesterone (P4) and (pregnancy-associated placental protein-A (PAPP-A)) essential for early pregnancy success and relate that to the expression of the cannabinoid receptors and enzymes that modulate AEA levels.

Results: The median plasma AEA level in non-viable pregnancies (1.