Failure of embryo implantation is a major limiting factor in early pregnancy and assisted reproduction. Determinants of implantation include the embryo viability, the endometrial receptivity, and embryo-maternal interactions. Multiple molecules are involved in the regulation of implantation, but their specific regulatory mechanisms remain unclear. MicroRNA (miRNA), functioning as the transcript...

OBJECTIVE To investigate whether early embryo cleavage kinetics were affected by type of culture media. METHODS In this prospective sibling-split study, 620 oocytes from 37 patients were randomly allocated into two groups: Cook group and Vitrolife group. Oocytes/embryos in Cook group, would be cultured with Cook sequential culture medium, while oocytes/embryos in Vitrolife group, would be cul...

The ultimate challenge for all in vitro fertilisation (IVF) clinics is to develop the ability to select for transfer the best single embryo first, from the patient’s cohort of embryos, thereby maximising the chance of pregnancy while the incidence of multiple pregnancies is kept to a minimum and fewer transfer cycles are required. This ambition has driven extensive research and development into...

Identification of new criteria for embryo quality is required to improve the clinical outcome of in vitro fertilization. The aim of this study was to determine the gene expression profile of cumulus cells (CC) surrounding the oocyte as biomarkers for embryo potential and to identify genes to be used as prognostic indicators of successful pregnancy. CC from single oocytes were analysed using DNA...

The concept of a phylotypic stage, when all vertebrate embryos show low phenotypic diversity, is an important cornerstone underlying modern developmental biology. Many theories involving patterns of development, developmental modules, mechanisms of development including developmental integration, and the action of natural selection on embryological stages have been proposed with reference to th...

Hormones must be balanced and dynamically controlled for the Female Reproductive Tract (FRT) to function correctly during menstrual cycle, pregnancy, delivery. Gamete selection successful transfer uterus, where it implants pregnancy occurs, is supported by mucosal epithelial lining of FRT ovaries, cervix, fallopian tubes, vagina. Successful implantation placentation in humans other animals rely...

Although the zebrafish possesses many characteristics that make it a valuable model for genetic studies of vertebrate development, one deficiency of this model system is the absence of methods for cell-mediated gene transfer and targeted gene inactivation. In mice, embryonic stem cell cultures are routinely used for gene transfer and provide the advantage of in vitro selection for rare events s...

BACKGROUND Embryos selection is crucial to maintain high performance in terms of pregnancy rate, reducing the risk of multiple pregnancy during IVF. Pronuclear and nucleolar characteristics have been proposed as an indicator of embryo development and chromosomal complement in humans, providing information about embryo viability. METHODS To correlate the zygote-score with the maternal age and ...

This review considers the value of single embryo transfer (SET) to prevent multiple pregnancies (MP) after IVF/ICSI. The incidence of MP (twins and higher order pregnancies) after IVF/ICSI is much higher (approximately 30%) than after natural conception (approximately 1%). Approximately half of all the neonates are multiples. The obstetric, neonatal and long-term consequences for the health of ...

Apart from the huge efforts made to develop an embryo in-vitro, the embryologist is faced with an even bigger task to choose an embryo from a cohort that will produce pregnancy. Selecting a single viable one is often a challenge to the embryologists and clinicians involved. This is because the one that is selected may determine outcome of the cycle. It is not in the embryologist interest to cho...