The high incidence of chromosome abnormalities in clinically recognised pregnancies is well documented, but experience of these problems at the time of conception is extremely limited. Using donated oocytes from women seeking surgical sterilisation, we have established reliable cytogenetic techniques for chromosome analysis of human pre-embryos. These have resulted in the first report of trisom...

Preimplantation genetic diagnosis allows to test the genetic status of embryos prior to implantation. In order to obtain genetic material, on which carry out a genetic diagnosis, a procedure named embryo biopsy is required. In the last two decades, embryo biopsy at the cleavage stage has been the mostly performed procedure. However, recently, alternative methods allowing the retrieval of a larg...

Centrosomin (CNN), a core Drosophila centrosome protein, interacts with the newly identified protein Centrocortin to promote cleavage furrow formation in the early embryo. Significantly, this activity is distinct from CNN's well-established role in centrosome-based microtubule organization.

Background: To examine the relative contributions of dietary fat intake level and its food sources and assisted reproduction parameters. Materials and Methods: A prospective study was conducted on 240 infertile women. In assisted reproduction treatment cycle, body mass index (BMI), physical activity (PA), calorie intake, fat consumption and major food sources were assessed. The number of retrie...

In order to clarify the relationships between the first cleavage plane and the embryonic axes, early cleavage pattern of the fertilized eggs of the starfish. Asterina pectinifera was reexamined. It was ascertained that the polar bodies were formed at the site to which the germinal vesicle had closely located before the initiation of the meiotic division, and that the first cleavage plane passed...

STUDY QUESTION What type of transferred embryo is associated with a lower rate of ectopic pregnancy? SUMMARY ANSWER The lowest risk of ectopic pregnancy was associated with the transfer of blastocyst, frozen and single embryo compared with cleavage stage, fresh and multiple embryos. WHAT IS KNOWN ALREADY Ectopic pregnancy is a recognized complication following assisted reproductive technolo...

Different models for animal cell cytokinesis posit that the stiffness of the equatorial cortex is either increased or decreased relative to the stiffness of the polar cortex. A recent work has suggested that the critical cytokinesis signaling complex centralspindlin may reduce the stiffness of the equatorial cortex by inactivating the small GTPase Rac. To determine if such a reduction occurs an...

BACKGROUND Hundreds of thousands of human embryos are cultured yearly at in vitro fertilization (IVF) centers worldwide, yet the vast majority fail to develop in culture or following transfer to the uterus. However, human embryo phenotypes have not been formally defined, and current criteria for embryo transfer largely focus on characteristics of individual embryos. We hypothesized that embryo ...