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Zhang J.,New Hope Fertility Center
Journal of Assisted Reproduction and Genetics

The maturation and meiotic competence of human oocyte requires both healthy cytoplasmic and nuclear compartments. Germinal vesicle (GV) transfer techniques have represented useful tools for studying the interaction between the nucleus and the cytoplasm in oocyte maturation process in mammals. This report summarizes an update on the recent findings on GV transfer pertaining to improving meiotic resumption and ability of immature oocytes to mature. It also addresses mitochondrial DNA heteroplasmy as a challenge in GV transfer technology. Altogether, data to date indicate that GV transfer could improve the quality of human oocytes especially in women with advanced maternal age who usually have high rates of spindle abnormality and chromosomal misalignment. Although experimental, this technique represents a viable therapeutic option for women with diminished ovarian reserve who do not produce mature oocytes or good embryos during IVF treatment. © 2014, Springer Science+Business Media New York. Source

Pertynska-Marczewska M.,Consultant in Obstetrics and Gynecology | Diamanti-Kandarakis E.,National and Kapodistrian University of Athens | Zhang J.,New Hope Fertility Center | Merhi Z.,New York University
Metabolism: Clinical and Experimental

Polycystic ovary syndrome (PCOS), a heterogeneous syndrome of reproductive and metabolic alterations, is associated with increased long-term risk of cardiovascular complications. This phenomenon has been linked to an increase in oxidative stress and inflammatory markers. Advanced glycation end products (AGEs) are pro-inflammatory molecules that trigger a state of intracellular oxidative stress and inflammation after binding to their cell membrane receptors RAGE. The activation of the AGE-RAGE axis has been well known to play a role in atherosclerosis in both men and women. Women with PCOS have systemic chronic inflammatory condition even at the ovarian level as represented by elevated levels of serum/ovarian AGEs and increased expression of the pro-inflammatory RAGE in ovarian tissue. Data also showed the presence of sRAGE in the follicular fluid and its potential protective role against the harmful effect of AGEs on ovarian function. Thus, whether AGE-RAGE axis constitutes a link between metabolic and endothelial dysfunction in women with PCOS is addressed in this review. Additionally, we discuss the role of hormonal changes observed in PCOS and how they are linked with the AGE-RAGE axis in order to better understand the nature of this complex syndrome whose consequences extend well beyond reproduction. © 2015 Elsevier Inc. Source

Minimal stimulation in vitro fertilization (mini-IVF) consists of a gentle controlled ovarian stimulation that aims to produce a maximum of five to six oocytes. There is a misbelief that mini-IVF severely compromises pregnancy and live birth rates. An appraisal of the literature pertaining to studies on mini-IVF protocols was performed. The advantages of minimal stimulation protocols are reported here with a focus on the use of clomiphene citrate (CC), gonadotropin releasing hormone (GnRH) agonist trigger for oocyte maturation, and freeze-all embryo strategy. Literature review and the author’s own center data suggest that minimal ovarian stimulation protocols with GnRH agonist trigger and freeze-all embryo strategy along with single embryo transfer produce a reasonable clinical pregnancy and live birth rates in both good and poor responders. Additionally, mini-IVF offers numerous advantages such as: i. Reduction in cost and stress with fewer office visits, needle sticks, and ultrasounds, and ii. Reduction in the incidence of ovarian hyperstimulation syndrome (OHSS). Mini-IVF is re-emerging as a solution for some of the problems associated with conventional IVF, such as OHSS, cost, and patient discomfort. © 2016, Royan Institute (ACECR). All Rights Reserved. Source

Zhang J.,New Hope Fertility Center
Reproductive Biology and Endocrinology

Background: Poor ovarian response and retrieval of no oocytes following ovarian stimulation for in vitro fertilization (IVF) is a challenging problem for both the patient and the clinician. Findings: Recent evidence indicates that folliculogenesis occurs in a wave-like fashion indicating that there are multiple follicular recruitment waves in the same menstrual cycle. This relatively new scientific concept provides new opportunities for the utilization of ovarian stimulation in women with poor ovarian response. This communication reports on the social and scientific rationale for the use of luteal phase ovarian stimulation following oocyte retrieval in the same cycle (also called double stimulation). Conclusions: Data to date showed that double ovarian stimulation in poor responders provides shorter time for retrieving mature oocytes with the potential formation of good quality embryos, and thus healthy pregnancies. © 2015 Zhang. Source

Shu Y.,New Hope Fertility Center | Shu Y.,Stanford University | Peng W.,New Hope Fertility Center | Zhang J.,New Hope Fertility Center
Reproductive BioMedicine Online

This study reports two clinical pregnancies and one live birth following the transfer of vitrified blastocysts developed from oocytes with neither zona pellucida nor corona cells. Two zona-free oocytes obtained from two patients of advanced maternal age undergoing minimal stimulation were normally fertilized after intracytoplasmic sperm injection. In case 1, all four blastomeres of the zona-free embryo were loosely associated and inserted back into ruptured zona on day 2. Zona-free embryo from case 2 had tight contacts between blastomeres and was cultured without zona. Both embryos derived from zona-free oocytes progressed to blastocyst stage and were cryopreserved by vitrification. When patients came back for a cryopreserved embryo transfer, both vitrified blastocysts survived warming. In case 1, transfer of a warmed blastocyst with reconstructed zona resulted in a clinical pregnancy that ended in a spontaneous abortion at 22 weeks. In case 2, live birth was achieved with a normal healthy baby (male) weighing 2381 g at 40 weeks' gestation. This report emphasizes the importance of maintenance of normal cell arrangement on the subsequent embryonic development for a zona-free oocyte. Zona-free oocytes may provide a valuable source of embryos for infertility patients, especially for those with a limited number of oocytes. © 2010, Reproductive Healthcare Ltd. Published by Elsevier Ltd. All rights reserved. Source

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