Interleukin-1 levels in the supernatant of conditioned media of embryos grown in autologous endometrial coculture: correlation with outcome after in vitro fertilization

Abstract

Problem: To determine if interleukin (IL)-1 produced by autologous endometrial coculture (AECC) was associated with outcome in patients with a history of multiple in vitro fertilization (IVF) failures.

Method of study: The conditioned media (CM) from AECC cells exposed or non-exposed to human embryos was analyzed for IL-1.

Results: Embryos grown on AECC demonstrated a significant improvement in number of blastomeres and fragmentation (frag) when compared to embryos grown in conventional media without ECC (6.4 +/- 1.3 vs. 5.5 +/- 1.2 blastomeres and 14.6 +/- 9.3%, vs. 18.4 +/- 9.8% frag; P< 0.008 and 0.003, respectively). When IL-1alpha and IL-1beta were undetectable in the CM, the embryos grown in ECC were of improved quality as compared to the embryos grown only in conventional media. Conversely, IL-1ra levels in the CM were positively associated with embryo quality. Exposure or non-exposure to an embryo did not result in differing levels of IL-1alpha, IL-1beta, or IL-1ra in the CM. IL-1beta levels were negatively associated with clinical pregnancy outcome (3.3 pg/mL (pregnant, n = 12) vs. 27.1 pg/mL (not pregnant, n = 17); P = 0.008, Mann Whitney U-test). IL-1alpha and IL-1ra levels were not associated with outcome.

Conclusions: We have demonstrated a significant improvement in blastomere number and frag with ECC. The presence of IL-1beta in the CM was negatively associated with embryonic development and clinical pregnancy. The presence of IL-1alpha in the CM was negatively associated with embryonic development and the presence of IL-1ra in the CM was positively associated with embryonic development. Whether IL-1beta itself interferes with successful outcome after embryo transfer or if it is a marker for undetected endometritis in the biopsy specimens remains to be determined.