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.

[Application of human oocyte morphometric parameters in assessment of fertilization and embryo development].

OBJECTIVE: To investigate the correlation of human oocyte morphometric parameters with fertilization and embryo development in the intracytoplasmic sperm injection (ICSI) cycles. METHODS: The morphometric parameters of oocytes collected and submitted to evaluation using OCTAX Eye-ware software just before ICSI. Oocyte diameter (OD), perivitelline space width (PSW), zonapellucida thickness (ZPT) and the shape of first polar body (FPB) (intact or fragmented) were analyzed. A stepwise multivariate Logistic regression was used to test the association between the morphometric parameters and fertilization and embryo development. RESULTS: In the study, 436 oocytes were measured and 370 were fertilized (84.9%), 225 fertilized oocytes were developed to high-quality embryos (60.8%). ZPT and PSW were associated with fertilization. The oocytes fertilized had thicker ZPT [(18.0±2.3) µm vs. (16.9±2.7) µm] and wider PSW [(14.4±3.3) µm vs. (13.2±3.9) µm]. The OD and shape of FPB were associated with embryos development. The oocytes developed to high-quality embryos had larger OD [(116.6±3.7) µm vs. (114.7±3.6) µm] and more intact FPB (86.2% vs. 66.7%). CONCLUSION: The morphometric parameters of oocytes can indicate fertilization and embryo development.