CAPSULE Mechanisms that control the survival of oocytes and, by extension, the duration of ovarian function have been identified. However, it is still not clear whether oocyte "quality" is related to survival, nor is the role of the granulosa cells of follicles in follicle survival entirely understood. Here, we consider oocyte-intrinsic and oocyte-extrinsic mechanisms of oocyte loss and argue t...

In the present study, various developmental stages of Liza aurata oocyte, especially IV and V stages have been described. On the basis of histological investigations, oocyte development in L. aurata comprises immature (I), the early maturing (II), the late maturing (III), mature (IV), ripe (V), and spent (VI) stages. In the stages I and II, nucleus occupied large volume of oocyte. Vacuolization...

OBJECTIVES To investigate whether a lower than expected number of oocyte after ≥14 mm follicle aspiration during OPU has any effect on pregnancy outcomes Methods: This is a retrospective study done between 2010 and 2013 at the IVF Unit of the Zeynep Kamil Women and Children Diseases Education and Research Hospital, dealing with the medical records of infertile patients who underwent IVF cycle a...

Background: Since the sheep ‘Dolly’ was successfully cloned by somatic cell nuclear transfer (SCNT), the inefficiency of SCNT cloning and abnormality of cloned animals have been a focus of considerable controversy. Oocyte quality has been shown to contribute to poor somatic cloning and cell reprogramming efficiency with many factors affecting oocyte quality and developmental potential. It has b...

The aim of the study was to examine whether oocyte yield could be an indicator of morphological oocyte quality and biological competency in patients younger than 36 years undergoing controlled ovarian stimulation (COS). Three hundred and thirty-five intracytoplasmic sperm injection (ICSI) procedures were arbitrarily subdivided into five groups according to the number of retrieved oocytes. Patie...

In mammals, observations of rapid shifts in mitochondrial DNA (mtDNA) variants between generations have led to the creation of the bottleneck theory for the transmission of mtDNA. The bottleneck could be attributed to a marked decline of mtDNA content in germ cells giving rise to the next generation, to a small effective number of mtDNA segregation units resulting from homoplasmic nucleoids rat...

Efforts have intensified to successfully mature and inseminate oocytes in vitro and then culture ensuing embryos to transferable stages from a large number of mammalian species. Success varies, but generally even for the most successful species it is only possible to obtain a maximum of a 40 to 50% development of zygotes to the blastocyst stage. Reduced oocyte developmental competence is sugges...