BACKGROUND Chemo- or radiotherapy can induce premature ovarian failure (POF), and ovarian tissue cryopreservation and transplantation may be proposed to restore ovarian function. Our aim was to evaluate the quality of oocytes and embryos derived from frozen-thawed transplanted ovarian tissue. MATERIALS AND METHODS Women were 21-28 years old at tissue cryopreservation. Nine women suffering POF...

Single-embryo transfer (SET) and more specifically elective SET (eSET) have taken their place in good clinical IVF/ICSI practice. After the initial cautious search for the characteristics of the twin-prone patient and of the selection of the embryo with the highest implantation potential many centres have embarked on the (progressive) implementation of SET, either by conviction or forced by leg...

For a long time, the cryopreservation of gametes and embryos remained a major hurdle for the clinicians and scientists in terms of success. However, recent technical advancement in the field of cryobiology has opened up various options for freezing gametes and embryos at different developmental stages. The tendency of the IVF world to switch over to naturalcycle IVF and to elective single-embry...

We investigated the feasibility of cryopreservation of zebrafish (Danio rerio) blastomeres and primordial germ cells (PGCs) by rapid freezing of dechorionated whole embryos at the blastula, gastrula and segmentation stages. Initially we examined the glass-forming properties and embryo toxicities of 5 cryoprotectants: methanol (MeOH), ethylene glycol (EG), dimethyl sulfoxide (DMSO), propylene gl...

For fertility patients undergoing in vitro fertilization (IVF), blastocyst culture brings a number of potential advantages over laboratory techniques leading to traditional cleavage-stage embryo transfer. Because day 2-3 embryos normally should transit the oviduct only, their direct exposure to an intrauterine microenvironment is physiologically inappropriate. This mismatch is obviated by blast...

The impact of intracytoplasmic sperm injection (ICSI) on cryopreserved zygotes and embryos was evaluated by comparing embryo survival and implantation between embryos derived from ICSI and those derived from standard insemination procedures. The study included patients whose excess zygotes and embryos were cryopreserved between September 1993 and December 1994 and who subsequently underwent a f...

The ice crystal formation is assumed as the most lethal factor for the failure of fish embryo cryopreservation and intracellular ice formation (IIF) plays a central role in cell injury during cooling. The objectives were to observe the morphological changes of red seabream (Pagrus major) embryo during the cooling-thawing process, and to examine the effect of cryoprotectant and cooling rate on t...

As the success rates of IVF clinics improve, one of the adverse consequences is the increased incidence of twins, due largely to the number of embryos transferred. Even if the number of embryos transferred is restricted to two, the twinning rate can exceed 40% of the pregnancies. An obvious way to reduce this high twin rate would be to transfer only one embryo. This would require that cryoprese...