Yasushi Kuribayashi

Sugiyama Clinic, Edo, Tōkyō, Japan

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Publications (10)11.47 Total impact

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    ABSTRACT: Zygote intrafallopian transfer (ZIFT) is an effective option for patients who have experienced repeated implantation failures (RIF) in assisted reproductive technology (ART) treatment. However, advance planning for the day of the operation can be problematic. Using a hormone replacement cycle (HRC) makes it possible to plan for the day of ZIFT. In the present study, we evaluated whether HRC-ZIFT is useful for RIF patients who have experienced difficulties obtaining morphologically good embryos in vitro.
    Archives of Gynecology and Obstetrics 06/2014; · 1.33 Impact Factor
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    ABSTRACT: To determine the efficacy of prostaglandin administration during the proliferative phase in order to improve pregnancy rates following frozen embryo transfer during a hormone replacement cycle (HRC). From September 2010 through March 2012, patients (n = 135) were recruited who had undergone oocyte retrieval during a stimulation cycle with clomiphene and had deferred fresh embryo transfer (ET) due to a thin uterine endometrium. All patients were less than 40 years of age and underwent thawed ET following all embryo cryopreservation, and were randomly divided into two groups for thawed ET using a conventional hormone replacement cycle with or without prostaglandin derivatives (prostaglandin or conventional group). Prostaglandin derivatives were administrated during the proliferative phase. Pregnancy and implantation rates following frozen ET were compared between the two groups. Although the endometrial thickness on the day of ET was similar for the prostaglandin and conventional groups, the pregnancy and implantation rates for the prostaglandin group were 40.0% and 22.0%, respectively, which was significantly higher than the rates for the conventional group (P < 0.01). Among patients who avoided fresh ET due to a thin endometrium, the pregnancy rate following a thawed cycle was low. However, it was improved when prostaglandin derivatives were used during the proliferative phase.
    Journal of Obstetrics and Gynaecology Research 04/2014; · 0.84 Impact Factor
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    ABSTRACT: AIM: The aim of this study was to observe the insides of the fallopian tubes of patients with unilateral or bilateral endometriomas by using salpingoscopy and evaluate the inner cavity of the fallopian tubes according to our original scoring system. MATERIAL AND METHODS: From April 2008 through December 2010, patients with unilateral or bilateral endometriomas were recruited (n = 157, endometrioma group). All patients underwent laparoscopic ovarian cystectomy and salpingoscopy. Using salpingoscopy, we observed the tubal lumen and calculated a fallopian tube score (F score) paying attention to the following six results: adhesions, loss of mucosal folds, rounded edges of mucosal folds, debris, foreign bodies, and abnormal vessels. The F scores were compared with those of the unexplained infertility patients who received those same procedures during the same period (n = 235; control group). RESULTS: Slightly more than three-quarters (75.9%) of the patients in the endometrioma group received F scores of 0, and this percentage was significantly higher than that for the control group (139/235 = 59.1%, P < 0.05). The pregnancy rate after conventional treatment for the endometrioma group was 21.7%, and all pregnant patients had achieved an F score of less than 2. CONCLUSION: It is highly possible that infertility patients with ovarian endometriomas are more likely to have intact fallopian tubes, by comparison with infertility patients who do not have ovarian endometriomas.
    Journal of Obstetrics and Gynaecology Research 04/2013; · 0.84 Impact Factor
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    ABSTRACT: To ascertain whether the use of hyaluronan-enriched transfer medium (HETM) improves pregnancy and implantation rates among embryo transfer patients with a history of multiple implantation failures. Patients (n = 314) under the age of 40 and with a history of multiple unsuccessful embryo transfers were enrolled. There were three groups of patients: those undergoing fresh embryo transfer (fresh ET [n = 111]), those undergoing vitrified-warmed ET in the natural cycle (WET-N [n = 101]) and those undergoing WET in a hormone replacement cycle (WET-H [n = 102]). On the day of ET, patients were randomized to HETM (0.5 mg/ml hyaluronan) or control medium containing no hyaluronan. Only patients with good quality embryos on day 3 were included. For all three patients groups (fresh ET, WET-N and WET-H) pregnancy rates (37.5 %, 31.4 % and 41.2 %, respectively) were significantly higher when using HETM compared with control medium (10.9 %, 10.0 % and 15.7 %, respectively; p < 0.05), and implantation rates when using HETM were also significantly higher compared with control medium (p < 0.05). Miscarriage rates were similar in both groups. HETM significantly increased pregnancy and implantation rates among embryo transfer patients with a history of multiple unsuccessful implantations-regardless of method used to prepare the endometrium.
    Journal of Assisted Reproduction and Genetics 04/2012; 29(7):679-85. · 1.82 Impact Factor
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    ABSTRACT: To build an evaluation scoring system using the results of salpingoscopy, and to evaluate the relationship between this scoring system and the outcome of pregnancy. Retrospective study. Sugiyama Clinic. Using salpingoscopy, we observed the tubal lumen, paying attention to the following six results: adhesions, loss of mucosal folds, rounded edges of mucosal folds, debris, foreign bodies, and abnormal vessels. From April 2008 through June 2009, 104 women in whom unexplained infertility had been diagnosed underwent salpingoscopy. The F scores were evaluated related with various clinical results or pregnancy rates. The F score expressed the sum of the abnormal results, and one abnormal result was given a 1-point F score. Approximately 60% of the patients showed an F score of 0, and the percentages of patients who showed 1, 2, 3, and ≥4 points were 19.2%, 11.5%, 4.5%, and 4.5%, respectively. After evaluation, 23 patients achieved pregnancy within a year. The pregnancy rates for patients with F scores of 0 and 1 point were 30.6% and 20.0%, respectively, and the rate of patients with an F score of 0 was significantly higher than the rate of patients with high F scores (F score ≥2; 9.1%). The patients showing a lower F score (0 or 1) showed higher fecundity than those showing an F score of ≥2.
    Fertility and sterility 12/2010; 94(7):2753-7. · 3.97 Impact Factor
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    ABSTRACT: To confirm whether women who choose to have one fresh embryo transferred and one frozen-and-thawed embryo when needed can dramatically reduce the possibility of a multifetal pregnancy while giving themselves a better chance of achieving pregnancy. We enrolled 685 patients who were undergoing assisted reproductive technology (ART) treatment at our clinic between January 2005 and December 2008. None of the patients had a history of ART treatment, and they received either a double-embryo transfer (DET) or single-embryo transfer (SET) during this period. The outcomes of the ART and the pregnancy rates per patient were evaluated for both groups and comparisons were made. The mean age was 35.7 +/- 0.2 years (mean +/- standard error of the mean) for all patients (n = 583) who received a fresh embryo cycle of DET. In contrast, the mean age (34.3 +/- 0.4) of all patients (n = 102) who received a fresh- or thawed-embryo transfer cycle of SET was significantly younger than the average age in the DET group (P < 0.05). The per-patient overall pregnancy rate in the SET group was an estimated 35.3%, which was significantly higher than that in the DET group (P = 0.02). However, the multifetal pregnancy rate for the DET group was significantly higher than that for the SET group (P < 0.01). We demonstrated that women who choose to have one fresh embryo transferred and one frozen-and-thawed embryo when needed, can dramatically reduce their possibility of a multifetal pregnancy while giving themselves a better chance of achieving pregnancy.
    Journal of Obstetrics and Gynaecology Research 08/2010; 36(4):777-82. · 0.84 Impact Factor
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    ABSTRACT: We attempted clinical application of a plastic blade, which is a novel cryopreservation device, for vitrification of human embryos and blastocysts. Between February 2003 and December 2007, a total of 4,430 Day 3 embryos from 898 patients (Day 3 group) and 55 blastocysts from 29 patients (blastocyst group) were vitrified and cryopreserved with a plastic device, and subsequently thawed for embryo transfer. Clinical outcomes after thawing and transfer of vitrified embryos and blastocysts were evaluated. In the Day 3 group, all embryos resulting from 1,441 oocyte retrieval cycles were recovered, and the thawed embryo survival rate was 98.4%. In the blastocyst group, the survival rate after thawing was 100%. A total of 3,026 day 3 embryos and 46 blastocysts were transferred. The pregnancy and implantation rates in the Day 3 group were 25.0% and 15.5%, respectively, and in the blastocyst group the rates were 24.2% and 26.1%, respectively. The miscarriage rates in the Day 3 and blastocyst groups were 18.3% and 50.0%, respectively. A plastic blade is a useful novel device in cryopreservation of vitrified human embryos.
    Journal of Assisted Reproduction and Genetics 04/2010; 27(4):161-7. · 1.82 Impact Factor
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    ABSTRACT: PurposeTo determine whether embryos cultured with a low oxygen level (2%) brought about beneficial effects on the outcome of ART. MethodsThis is a sequential case–control embryo-culture study. Embryos were cultured either with a gas mixture containing 2% O2, 5% CO2, and 93% N2 (low-oxygen group) or 5% O2, 5% CO2, and 90% N2 (conventional group). From January 2008 to September 2008, 873 fertilized oocytes were obtained from 250 patients in the low-oxygen group and from October 2008 to March 2009, 730 fertilized oocytes were obtained from 213 patients in the conventional group. The outcomes of ART were compared between two groups. ResultsThe cleavage rate in the low-oxygen group (94.4%) was similar to that (94.7%) in the conventional group. The mean number of blastomeres on Day 3 in the low-oxygen group (mean±SE) was 6.5±1.9, and this was significantly lower than in the conventional group (6.8±1.9, p<0.05). Moreover, the low-oxygen group produced worse quality embryos, on the basis of the significantly higher embryo grade 2.1±0.6 versus 1.9±0.6, p<0.001, in 5% oxygen. The pregnancy and miscarriage rates in the low-oxygen group were 22.3 and 20.8%, respectively, which were statistically similar to the outcomes in the conventional group. ConclusionsOverall, culture of embryos at the low oxygen level did not significantly improve ART results compared with embryos grown in 5% oxygen. The study suggests that a low oxygen level worsens embryo morphology but does not impair embryo viability. KeywordsART-Embryo development-Embryo quality-High oxygen-Low oxygen
    Reproductive Medicine and Biology 01/2010; 9(3):163-168.
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    ABSTRACT: Purpose The purpose was to establish a mild ovarian stimulation protocol that would help assisted reproductive technology (ART) units to avoid scheduling on weekends. Methods This protocol directed patients to take 50 mg/day of clomiphene citrate between days 3 and 7 of the menstrual cycle: 225 IU of recombinant follicle-stimulating hormone (rec-FSH) were administered on days 3, 5 and 7; human chorionic gonadotropin (hCG) was administered on day 9; and, oocyte pick-up (OPU) was planned for day 11. From October 2008 through October 2009, 514 women underwent ART treatment with mild stimulation at the Sugiyama Clinic, and we evaluated whether OPU was accomplished on the planned day. Results Of all the treatment cycles, 419 (81.5%) underwent OPU on day 11 (scheduled group). Additional rec-FSH administration was needed in 83 cycles, in which case OPU was performed on day 12 or later. In 12 cycles, OPU was canceled. The unscheduled group (n = 95) consisted of delayed OPU cycles and canceled cycles. Of all treatment cycles, 332 cycles in the scheduled group and 68 cycles in the unscheduled group underwent embryo transfer, with 81 and 16, respectively, resulting in pregnancies. Conclusions Using this protocol, OPU was performed on the scheduled day in about 80% of the cycles. Most weekend scheduling of OPU can be avoided using this mild stimulation.
    Reproductive Medicine and Biology 11(2).
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    ABSTRACT: Purpose The purpose of this study was to investigate how many oocytes are needed to achieve an adequate pregnancy rate per 1 oocyte retrieval cycle in mild ovarian stimulation. Methods This protocol consisted of clomiphene citrate and recombinant-follicle-stimulating hormone injection without a gonadotropin-releasing hormone-antagonist. From January 2009 through December 2010, there were 1,227 women who underwent assisted reproductive technologies treatment with mild stimulation at the Sugiyama Clinic. The overall pregnancy rate per single oocyte retrieval cycle was evaluated using both fresh and cryopreserved-and-thawed embryos according to the retrieved oocyte number. Results According to the retrieved oocyte number, a total of 1,227 cycles were divided into 4 groups: group A (the oocyte number <4; 433 cycles), group B (the oocyte number = 4, 5; 317 cycles), group C (the oocyte number = 6, 7; 206 cycles), and group D (the oocyte number ≥8; 271 cycles). The overall pregnancy rates for groups A, B, C, and D were 22.2, 42.9, 52.4, and 56.0 %, respectively, the rates for groups C and D were significantly higher than that for group A (p < 0.01). Conclusions The optimal number of retrieved oocytes proved to be between 6 and 7 for the patients who received our milder stimulation protocol and experienced no reduction in their overall pregnancy rate.
    Reproductive Medicine and Biology 12(3).