New candidate genes to predict pregnancy outcome in single embryo transfer cycles when using cumulus cell gene expression

Abstract

Objective: To relate the gene expression in cumulus cells surrounding an oocyte to the potential of the oocyte, as evaluated by the embryo morphology (days 3 and 5) and pregnancy obtained in single-embryo transfer cycles.

Design: Retrospective analysis of individual human cumulus complexes using quantitative real-time polymerase chain reaction for 11 genes.

Setting: University hospital IVF center.

Patient(s): Thirty-three intracytoplasmic sperm injection patients, of which 16 were pregnant (4 biochemical and 12 live birth).

Intervention(s): Gene expression analysis in human cumulus complexes collected individually at pickup, allowing a correlation with the outcome of the corresponding oocyte. Multiparametric models were built for embryo morphology parameters and pregnancy prediction to find the most predictive genes.

Main outcome measure(s): Gene expression profile of 99 cumulus complexes for 11 genes.

Result(s): For embryo morphology prediction, TRPM7, ITPKA, STC2, CYP11A1, and HSD3B1 were often retained as informative. Models for pregnancy-biochemical or live birth-complemented or not with patient and cycle characteristics, always retained EFNB2 and CAMK1D together with STC1 or STC2. Positive and negative predictive values of the live birth models were >85%.

Conclusion(s): EFNB2 and CAMK1D are promising genes that could help to choose the embryo to transfer with the highest chance of a pregnancy.