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Background: Investigating the mechanisms of human primordial germ cell (PGC) and gamete development are important for understanding the causes of infertility and effects of environmental chemicals on reproductive development. However, there are practical and ethical difficulties associated with obtaining human tissue in early development. The aim of this study was to investigate whether human embryonic stem cell-hESC-generated germ cells could provide an in vitro model of gamete development.Method: Human ESCs were differentiated as embryoid bodies (EBs) in vitro. Gene and protein marker expression profiles of EBs in different periods of culture were analysed by quantitative polymerase chain reaction (Q-PCR) and immunolocalization to monitor germ cell development. Secretion of hormones involved in germ cell maturation was measured, to detect the existence of a germ cell niche within EBs.Results: Q-PCR revealed gene expression profiles consistent with PGC formation and germ cell development. A small population of post-meiotic spermatid cells were identified using sperm-specific antibodies (Protamine 1 and 1.97). Although gene expression profiles characteristic of oocyte development and follicle-like structures were detected, a committed oocyte with extra-cellular zona pellucida was not recognized with zona pellucida-specific monoclonal antibody.Conclusions: hESCs can form PGCs and post-meiotic spermatids in vitro, however, there remains doubt about oocyte development. Levels of steroid hormones produced by EBs were significant when compared with known values for a similar quantity of human testis, suggesting that hESC may intrinsically create a favourable hormonal niche for spermatogenesis. [ABSTRACT FROM AUTHOR]

Introduction: Controlled ovarian hyperstimulation (COH) plays important role in reproductive medicine because selection of appropriate ovarian stimulation strategy can improve assisted reproductive technology outcomes. Antimullerian hormone (AMH) is a predictor of ovarian response, which can help to select the best treatment strategies in women undergoing agonist and antagonist protocols to optimize safety and clinical pregnancy rates. Materials and Methods: This study is a retrospective study conducted in a private assisted reproductive unite and a total of 243 patients with tubal factor infertility are selected. Results: In both of GnRH agonist and antagonist protocol, with increasing of AMH level, oocyte and good embryo number is increased. On the other hand in AMH<1.1, > 2.8 ng/ml levels, GnRH agonist leads to higher oocyte and embryo number that is significant. On the contrary, pregnancy rate with increasing of AMH level is not increased and the highest rate of pregnancy is observed in AMH 1.1-2.8 ng/ml levels that it observed with antagonist protocol. Conclusion: Based on AMH levels we can predict assisted reproductive outcomes. In three range of AMH levels, GnRH agonist protocol can lead to better results. In the women with poor prognosis and low and high levels of AMH, it should focus on improving results with increasing of endometrial receptivity or embryo quality. [ABSTRACT FROM AUTHOR]