Soluble MHC Class I chain-related molecule serum levels are predictive markers of implantation failure and successful term pregnancies following IVF.

BACKGROUND Despite ongoing progresses of IVF techniques, biomarkers predicting their outcome prior to IVF initiation are lacking. We investigated whether serum levels of the stress-inducible soluble major histocompatibility complex Class I chain-related molecule, MICA, (sMIC), a regulator of cellular immunity, can be predictive of implantation or pregnancy failure after IVF. METHODS sMIC serum levels, evaluated during the follicular phase of the cycle preceding in vitro fertilization, in a cohort of 170 infertile women with 22.3% IVF success rate were analyzed in association with implantation/pregnancy failure or live birth outcomes after IVF. RESULTS sMIC serum levels, detected in 38% of all women undergoing IVF, were shown to be predictive both of implantation failure (> or = 2.45 ng/ml cut off, odds ratio (OR) = 4.6; 95% confidence interval (CI) = 1.08 - 19.79; P = 0.031) and successful pregnancy (< 2.45 ng/ml, OR = 13.8; 95% CI = 2.03-118.3; P = 0.002). When successful implantation occurred, sMIC levels > 3.2 ng/ml were predictive of spontaneous abortion (OR = 35; 95% CI = 1.74-703; P = 0.026). CONCLUSIONS sMIC is thus to be considered as a novel blood biomarker which, when quantified prior to initiation of IVF, anticipates chances for infertile women to give birth to a viable baby. Considering medical and psychological cost of IVF, this non-invasive assay may thus contribute to better counseling, treatment and care of infertile couples prior to IVF.