Before implantation into the uterine wall, the mammalian embryo undergoes a period of cell division, cell shape change, and cell differentiation leading to the formation of an outer epithelium, the trophectoderm. The trophectoderm is the part of the embryo that initiates uterine contact and, after transformation to become the trophoblast, uterine invasion. Similar to the kidney nephron, the tro...

Recent studies have suggested that leptin plays an important role in reproduction. Ob-R is expressed in the murine embryo, and is suggested to play a role in embryo development, although contradictory results have been reported. In the present study, Ob-R expression was observed both at the mRNA and protein levels in porcine early embryos. We have also demonstrated that leptin is produced in th...

It is generally believed that progesterone is essential for inducing the changes in oviduct and uterus necessary for embryo viability and implantation in a number of mammalian species. The aim of this study was, in the rhesus monkey, to examine in conception cycles with and without early luteal phase antiprogestin (mifepristone; RU 486) treatment: (i) the growth status of preimplantation embryo...

According to the "developmental origin of health and disease" hypothesis, the metabolic set points of glucose and lipid metabolism are determined prenatally. In the case of a diabetic pregnancy, the embryo is exposed to higher glucose and lipid concentrations as early as during preimplantation development. We used the rabbit to study the effect of maternal diabetes type 1 on lipid accumulation ...

In 2005, the European Society for Human Reproduction and Embryology (ESHRE) Preimplantation Genetic Diagnosis (PGD) Consortium published a set of Guidelines for Best Practice to give information, support and guidance to potential, existing and fledgling PGD programmes (Thornhill AR, De Die-Smulders CE, Geraedts JP, Harper JC, Harton GL, Lavery SA, Moutou C, Robinson MD, Schmutzler AG, Scriven P...

Preimplantation embryo development is an important and unique period and is strictly controlled. This period includes a series of critical events that are regulated by multiple signal-transduction pathways, all of which are crucial in the establishment of a viable pregnancy. The p38 mitogen-activated protein kinase (MAPK) signalling pathway is one of these pathways, and inhibition of its activi...

Myo-inositol (myo-Ins) has a physiological role in mammalian gametogenesis and embryonic development and a positive clinical impact on human medically assisted reproduction. We have previously shown that mouse embryo exposure to myo-Ins through preimplantation development in vitro increases proliferation activity and blastocyst production, representing an improvement in culture conditions. We h...

Consideration of embryo-derived growth factors, such as IGF1, is important when culturing an embryo in an in vitro fertilization (IVF) setting, or when studying the effect of growth factors on embryo development in vitro. Addition of IGF1 to the culture medium has been reported to cause a range of developmental responses in preimplantation mouse embryos. This variability may be due to culture o...

Mammalian preimplantation development, which is the period extending from fertilization to implantation, results in the formation of a blastocyst with three distinct cell lineages. Only one of these lineages, the epiblast, contributes to the embryo itself, while the other two lineages, the trophectoderm and the primitive endoderm, become extra-embryonic tissues. Significant gains have been made...

With readily available transcriptome-wide data, understanding the role of each expressed gene is an essential next step. Although RNAi technologies allow for genome-wide screens in cell culture, these approaches cannot replace strategies for discovery in the embryo. Here we present, for the first time, a knockdown screen in mouse preimplantation embryos. Early mammalian development encompasses ...