A corpus luteum is not a prerequisite for the expression of progesterone induced blocking factor by T-lymphocytes a week after implantation.

摘要

PURPOSE: To determine if production of the immunomodulatory protein, progesterone induced blocking factor (PIBF), requires merely progesterone or whether other factors made by the corpus luteum are required. METHODS: The percentage of peripheral lymphocytes expressing PIBF was determined by obtaining a blood sample from women 9-12 days after embryo transfer. The embryos were either fresh ones following hyperstimulation and oocyte retrieval or were frozen-thawed embryos. Preparation for frozen embryo transfer required corpus luteum suppression with exogenous estrogen. The percentage of lymphocytes expressing PIBF was determined by an immunocytochemistry method. RESULTS: PIBF expression (>1%) was found in 20.5% of COH and 13.3% of frozen embryo transfer cycles. There either was a significant difference or a trend for higher pregnancy rates when PIBF expression was detected. CONCLUSIONS: These data corroborate previous conclusions that PIBF is detected in a minority of women in the late luteal phase. A corpus luteum is not required for its expression.