Screening of miRNAs in human follicular fluid reveals an inverse relationship between microRNA-663b expression and blastocyst formation.

Research Question: Are miRNAs found in follicular fluid related to blastocyst formation from the corresponding oocytes?

Design: In this study, 91 individual follicular fluid samples from single follicles containing mature oocytes from 91 women were collected and classified into group 1 (n = 38) with viable blastocysts, and group 2 (n = 53) with no blastocyst. TaqMan human miRNA cards and quantitative reverse transcription polymerase chain reaction were used to identify differently expressed follicular fluid miRNAs between the two groups.

Results: We found MIR-663B to be significantly differentially expressed in follicular fluid of oocytes that yielded viable blastocysts versus those that did not develop into blastocysts (14.16 ± 7.00 versus 23.68 ± 17.02; P = 0.019), as well as for those which develop into blastocysts with good morphology versus those with poor morphology (11.69 ± 3.49 versus 20.16 ± 9.33; P = 0.003).

Conclusions: MIR-663B expression levels in human follicular fluid samples were significantly negatively related to viable blastocyst formation and may become an objective evaluation criterion for embryo development potential after IVF.