Biomedical subjects

Miyuki Nagaki

Publications and source records attributed to Miyuki Nagaki.

3 recordsLinked to original sources

PubMed2004

A prospective, randomized study: day 3 versus hatching blastocyst stage.

BACKGROUND: Recently, advances in human IVF-embryo transfer (ET) have been reported using sequential media and blastocyst stage ET. In our previous report, using a prospective, randomized study, no advantage was found using the blastocyst stage ET compared with day 3 ET. This study was performed in order to evaluate implantation and pregnancy rates of hatching blastocyst stage ET compared with conventional day 3 ET. METHODS AND RESULTS: A total of 480 patient cycles were evaluated using a prospective, randomized study. The pregnancy rate and implantation rate were compared between the day 3 ET (n = 240) and hatching blastocyst stage ET (Hat ET; n = 240). The Hat ET group had a pregnancy rate of 29.3% (55 out of 188) and an implantation rate of 21.4% (67 out of 313). The day 3 ET group had a pregnancy rate of 29.2% (70 out of 240) and an implantation rate of 19.1% (93 out of 488). In the Hat ET group, the pregnancy rate, implantation rate and ongoing pregnancy rate of day 5 ET and day 6 ET were all higher than the respective rates in the day 7-9 ET group. CONCLUSION: We found that the pregnancy rate and implantation rate of ET with hatching stage blastocysts had no advantage compared with the conventional day 3 ET.

Adult↗

PubMed2004

Developmental potential and chromosomal constitution of embryos derived from larger single pronuclei of human zygotes used in in vitro fertilization.

Blastocysts that develop from larger 1 pronuclear zygotes are suspected to be diploid and are comparable in development potential to 2 pronuclear zygotes.

Chromosomes↗

PubMed2002

A prospective trial of blastocyst culture and transfer.

BACKGROUND: The aim of this study was to evaluate the effectiveness of the blastocyst culture method compared with the conventional day 3 transfer method using a prospective trial. METHODS: A total of 235 patients with 273 cycles were evaluated for a period of almost 1 year. Depending upon the sequence in which the ovum retrieval was performed, patients were prospectively assigned (alternate allocation) to a culture period of 3 or 5 days duration. Embryos were transferred either on day 3 (after culture in human tubal fluid) or on day 5 (after culture in sequential media). RESULTS: The pregnancy rates after embryo transfer on days 3 and 5 were similar at 26.5 and 25.9% respectively. Among the day 5 embryo transfer group, patients were divided into three groups corresponding to three sequential media. The pregnancy rates were 32.0% using Irvine blastocyst medium, 6.9% using G1.2/G2.2 and 32.4% using Cook blastocyst medium. CONCLUSIONS: The results of our study were not as successful as previous studies had been. Additionally, there may have been problems in day 5 embryo transfer, such as choosing the sequential media, quality control, contamination and so on. From the results of this study, it appears that day 5 embryo transfer has no advantages for ordinary patients of assisted reproductive technology.

Adult↗