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Allahbadia G.N.,Rotunda The Center for Human Reproduction | Morimoto Y.,IVF Namba Clinic
Ovarian Stimulation Protocols | Year: 2015

Ovarian Stimulation Protocols is a concise handbook that aims to deliver everything the reader needs to know for performing a risk-free ovarian stimulation for assisted reproductive technique (ART) and get a favorable outcome. Review of crucial issues such as the significance of monitoring ovarian stimulation, advantages and disadvantages of ovarian hyperstimulation versus minimal stimulation, and the use of various drug regimens and stimulation protocols for various patient sub-sets, will help clinicians in selecting the better or more appropriate protocols. The contributors of this book have leading scientific and clinical backgrounds, with years of experience to support their views. The book serves as a handy practical guide, targeting and settling clinical dilemma that ART practitioners commonly experience in their clinics, while providing a window to the newer developments. © Springer India 2016. Source

Hashimoto S.,IVF Namba Clinic | Kato N.,Kinki University | Saeki K.,Kinki University | Morimoto Y.,IVF Namba Clinic
Fertility and Sterility | Year: 2012

Objective: To assess the developmental kinetics of human embryos and their ability to develop to morphologically normal blastocysts. Design: Experimental study on human embryos donated for research using a time-lapse imaging system based on individual embryo culture in poly(dimethylsiloxane) microwells and monitored using a microscope inside the incubator. Setting: Private fertility clinic. Patient(s): Surplus embryos donated by couples after undergoing fertility treatment. Intervention(s): None. Main Outcome Measure(s): Blastocyst score and times required from beginning to completion of the second and third mitotic divisions. Result(s): The time required for completion of the second division (the three- to four-cell stage) was shorter in embryos that developed to high-scoring blastocysts (0.7 hours, n = 17) than in those forming low-scoring blastocysts (3.7 hours, n = 24). Similarly, the mean time required to completion of the third division (five- to eight-cell stage) was also significantly shorter in embryos forming high-scoring blastocysts (5.7 hours) than among those forming low-scoring blastocysts (16.9 hours). Conclusion(s): Individual embryos with the potential to develop to high-scoring blastocysts could be selected at 2-3 days of culture using this system by examining the times required to complete the second and third mitotic divisions. © 2012 American Society for Reproductive Medicine, Published by Elsevier Inc. Source

Suzuki N.,St. Marianna University School of Medicine | Yoshioka N.,St. Marianna University School of Medicine | Takae S.,St. Marianna University School of Medicine | Sugishita Y.,St. Marianna University School of Medicine | And 4 more authors.
Human Reproduction | Year: 2015

study question: Is ovarian tissue cryopreservation using vitrification followed by in vitro activation (IVA) of dormant follicles a potential approach for infertility treatment of patients with primary ovarian insufficiency (POI)? summaryanswer: Our vitrification approach followed by IVA treatment is a potential infertility therapy for POI patients whose ovaries contain residual follicles. what is known already: Akt (protein kinase B) stimulators [PTEN (phosphatase with TENsin homology deleted in chromosome 10) inhibitor and phosphatidyinositol-3-kinase (PI3 kinase) stimulator] activate dormant primordial follicles in vitro and ovarian fragmentation disrupts the Hippo signaling pathway, leading to the promotion of follicle growth.We treated POI patients with a combination of ovarian vitrification, fragmentation and drug treatment, followed by auto-transplantation, and reported successful follicle growth and pregnancies. study design, size, duration: Prospective clinical study of 37 infertile women with POI between 12 August 2011 and 1November 2013.We enrolled 10 new patients since the previous publication. participants/materials, setting, methods: POI patients were originally selected based on a history of amenorrhea for more than 1 year and elevated serum FSH levels of.40 mIU/ml (n = 31) but this was later changed to.4 months, age,40 years and serum FSH levels of.35 mIU/ml (n = 6) (mean 71.8±30.8, range 35.5-197.6) so as to include patients with a shorter duration of amenorrhea. Under laparoscopic surgery, ovariectomywas performed and ovarian cortices were dissected into strips for vitrification. Some pieces were examined histologically. After warming, two to three strips were fragmented into smaller cubes before culturing with Akt stimulators for 2 days. After washing, ovarian cubes were transplanted beneath the serosa of Fallopian tubes under laparoscopic surgery. Follicle growth was monitored by ultrasound and serum estrogen levels. After oocyte retrieval from mature follicles, IVF was performed. main results and the role of chance: Among 37 patients, 54% had residual follicles based on histology. Among patients with follicles, 9 out of 20 showed follicle growth in auto-grafts with 24 oocytes retrieved from six patients. Following IVF and embryo transfer into four patients, three pregnancies were detected based on serum hCG, followed by one miscarriage and two successful deliveries. For predicting IVA success, we found that routine histological analyses of ovarian cortices and shorter duration from initial POI diagnosis to ovariectomy are valid parameters. limitations, reasons for caution: Although our findings suggest that the present vitrification protocol is effective for ovarian tissue cryopreservation, we have not compared the potential of vitrification and slow freezing in follicle growth after grafting. We chose the serosa of Fallopian tubes as the auto-grating site due to its high vascularity and the ease to monitor follicle growth. Future studies are needed to evaluate the best auto-grafting sites for ovarian tissues. Also, future studies are needed to identify biological markers to indicate the presence of residual follicles in POI to predict IVA treatment outcome. wider implications of the findings: In POI patients, ovarian reserve, namely the pool of residual follicles, continues to diminish with age. If one ovary is cryopreserved at an earlier stage of POI, patients could undergo additional non-invasive infertility treatments before the final decision for the IVA treatment. Furthermore, in the cases of unmarried POI patients, cryopreservation of ovarian tissues allows their fertility preservation until they desire to bear children. study funding/competing interest(s): This work was supported by Grant-In-Aid for Scientific Research (Research B: 24390376, Challenging Exploratory Research: 24659722, and Innovative Areas, Mechanisms regulating gamete formation in animals: 26114510) and by research funds fromthe Smoking Research Foundation, and the Takeda Science Foundation. None of the authors has a conflict of interest. trial registration number: UMIN000010828. © 2015 The Author. Source

Sakakibara Y.,RIKEN | Hashimoto S.,IVF Namba Clinic | Nakaoka Y.,IVF Namba Clinic | Kouznetsova A.,Karolinska Institutet | And 2 more authors.
Nature Communications | Year: 2015

The frequency of chromosome segregation errors during meiosis I (MI) in oocytes increases with age. The two-hit model suggests that errors are caused by the combination of a first hit that creates susceptible crossover configurations and a second hit comprising an age-related reduction in chromosome cohesion. This model predicts an age-related increase in univalents, but direct evidence of this phenomenon as a major cause of segregation errors has been lacking. Here, we provide the first live analysis of single chromosomes undergoing segregation errors during MI in the oocytes of naturally aged mice. Chromosome tracking reveals that 80% of the errors are preceded by bivalent separation into univalents. The set of the univalents is biased towards balanced and unbalanced predivision of sister chromatids during MI. Moreover, we find univalents predisposed to predivision in human oocytes. This study defines premature bivalent separation into univalents as the primary defect responsible for age-related aneuploidy. © 2015 Macmillan Publishers Limited. All rights reserved. Source

Hashimoto S.,IVF Namba Clinic | Suzuki N.,Kanagawa University | Yamanaka M.,IVF Namba Clinic | Hosoi Y.,Kinki University | And 2 more authors.
Reproductive BioMedicine Online | Year: 2010

This study assessed the effects of vitrification solutions and equilibration times on morphology of cynomolgus ovarian tissues. Ovarian cortical sections (0.1-0.2 cm thickness) of seven cynomolgus monkeys were randomly allocated to either a control group or one of six vitrification groups. Ovarian tissue sections were vitrified ultra-rapidly by placing them directly into liquid nitrogen using two different vitrification solutions (VSEGP: 5.64 mol/l ethylene glycol + 5% (w/v) polyvinylpyrrolidone + 0.5 mol/l sucrose; and VSED: 3.22 mol/l ethylene glycol + 2.56 mol/l dimethylsulphoxide + 0.5 mol/l sucrose) after three different exposure times (5-20 min). After warming, follicle morphology was analysed using light and transmission electron microscopy. The proportion of morphologically normal follicles vitrified using VSED after a 5-min exposure was lower (P < 0.05) than those vitrified by other conditions. The proportion of normally structured mitochondria in oocytes of preantral follicles vitrified after a 5-min exposure to VSED (56%) was lower (P < 0.01) than those vitrified by other conditions (78-88%). Following tissue vitrification with VSED, the surface ratio of lysosome was increased compared with non-vitrified oocytes (1.64% versus 1.11%; P < 0.05). These results indicate that VSEGP can support the morphology of vitrified preantral follicles and oocytes. © 2010, Reproductive Healthcare Ltd. Published by Elsevier Ltd. All rights reserved. Source

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