How general semen quality influences the blastocyst formation rate: Analysis of 4205 IVF cycles.

OBJECTIVE: To select embryos with higher implantation potential, the extended culture has been the most frequently applied strategy worldwide, and consequently leads to higher live birth rates per transfer. Sperm quality is a determining feature, and it may influence the outcomes of IVF from fertilization to embryo development. Therefore, we hypothesize that blastocyst formation may also be impaired by general semen quality. METHODS: We analyzed 4205 IVF cycles. Four study groups were designed according to semen quality: normal, mild alteration, severe alteration and epididymis. All cycles were intended to extend embryo culture until the blastocyst stage, and embryo development was evaluated. RESULTS: Regarding cleavage rate, the normal and mild alteration semen groups were equivalent, and the severe alteration and epididymis semen groups were equivalent to each other. The blastocyst formation rate decreased with semen quality. At least one blastocyst formed in 79.9% of cycles for the normal semen group, whereas the percentage of cycles with the formation of at least one blastocyst was slightly lower for the mild alteration (75.6%), severe alteration (76.4%) and epididymis (76.8%) semen groups. A multivariate logistic regression showed that for each additional cleaved embryo on day 3, the chance of having at least one blastocyst doubles. Additionally, the chance of having at least one blastocyst decreased when semen presented mild or severe alterations. CONCLUSION: The general quality of sperm is a good predictor of blastocyst formation, significantly affecting the likelihood of having at least one blastocyst at the end of the cycle. Based on our findings, it is necessary to consider general semen quality and the number of cleaved embryos when forecasting the possibility of blastocyst formation and transfer in an extended culture system.

Does slow embryo development predict a high aneuploidy rate on trophectoderm biopsy?

The aneuploidy rates in expanded blastocysts biopsied on days 5 and 6 development were assessed in women undergoing IVF followed by array comparative genomic hybridization. This study included 1171 expanded blastocysts from 465 patients. Among the 465 patients, 215 and 141 underwent embryo biopsy on day 5 and day 6 (46.2% and 30.3%, respectively), and 109 underwent biopsy on both days 5 and 6 (23.4%). The cycles of 206 women were cancelled because only aneuploidy embryos were present (44.3%). The aneuploid embryos were classified according to the type as single, double or complex aneuploidy. No differences were observed in the distributions of these three categories according to the day of the biopsy. The aneuploidy rate was also evaluated according to maternal age, and was found to be higher in older patients; however, no differences in this rate were detected between embryos biopsied on days 5 and 6 according to maternal age. Biopsy was carried out when blastocysts reached the expanded stage. The embryos biopsied on day 6 had a higher rate of aneuploidy (69.9%) than those biopsied on day 5 (61.4%); however, the euploid embryos transferred had similar chances for successful and healthy gestation.