Today, in vitro fertilization (IVF) is not just a medical issue, but certainly also a complex legal issue, in which lawyers can play an important role by establishing the suitable legal conditions to regulate legal relations by introducing necessary theories. One of the important and controversial issues, which can be approached legally, is the study of the pre-implantation embryo with regard t...

In amniotes, primitive endoderm (PrE) plays important roles not only for nutrient support but also as an inductive tissue required for embryo patterning. PrE is an epithelial monolayer that is visible shortly before embryo implantation and is one of the first three cell lineages produced by the embryo. We review here the molecular mechanisms that have been uncovered during the past 10 years on ...

The binding pattern of a rabbit antiserum raised against mouse-ectoplacental-cone trophoblast on component cell populations in the pre-implantation and early post-implantation mouse embryo has been examined at the electron-microscope level using an immunoperoxidase-labelling technique. Binding was not detectable on the 1-cell stage, appeared at low levels at the 8-cell stage and was heavy on th...

Natural human embryonic mortality is generally considered to be high. Values of 70% and higher are widely cited. However, it is difficult to determine accurately owing to an absence of direct data quantifying embryo loss between fertilisation and implantation. The best available data for quantifying pregnancy loss come from three published prospective studies (Wilcox, Zinaman and Wang) with dai...

Background: Somatic cell nuclear transfer, commonly known as cloning is a powerful tool for the production of identical animals for productive, biomedical or conservation purposes. Today several species of mammals has been cloned using this technology. Nevertheless, the efficiency of the process is still low in terms of newborn animals. The causes for such inefficiencies are mainly the lack of ...

The investigation into lineage allocation and early asymmetries in the pre- and peri-implantation mouse embryo is gaining momentum. As we review here, new insights have been gained into the cellular and molecular events that lead to the establishment of the three lineages of the blastocyst, to the determination of the origin and the fates of the visceral endoderm in the peri-implantation mouse ...