background: it has been demonstrated that performing a mock embryo transfer (et) significantly improves the pregnancy rate in ivf cycles. the mock et could be performed prior to the stimulation cycle or immediately before real et. the problem of the first procedure is the possibility of variation in the uterine position and or cervico�uterine angle. objective: the purpose of this study was to d...

Frozen-thawed (FT) embryo transfer is a procedure used for the storage and transfer of excess embryos obtained during in vitro fertilization- intracytoplasmic sperm injection cycles. In recent years, improvements in laboratory conditions and limitations on the number of embryos to be transferred have led to a progressive increase in FT embryo transfer cycles. However, the best solution for endo...

Recent dramatic increases in success rates with frozen-thawed embryo transfer (FET) are encouraging, as are numerous findings of several reduced risks with FET when compared with fresh transfer. These reduced risks include low birth weight and prematurity, among others. However, FET is also associated with increased risks of macrosomia and large for gestational age. There have been reports of g...

BACKGROUND As embryo selection is not allowed by law in Switzerland, we need a single early scoring system to identify zygotes with high implantation potential and to select zygotes for fresh transfer or cryopreservation. The underlying aim is to maximize the cumulated pregnancy rate while limiting the number of multiple pregnancies. METHODS In all, 613 fresh and 617 frozen-thawed zygotes wer...

Continuous improvements to assisted reproductive technology (ART) have facilitated the advancement and preservation of animal genetics as well as animal reproductive efficiency. One of the ART techniques is cryopreservation which facilitates embryo transfer procedures. In the present experiment embryos produced in vivo or in vitro were transferred to the recipient ewes just after collection (fr...

A commercially viable cattle embryo transfer (ET) industry was established during the early 1970s. Initially, techniques for recovering and transferring cattle embryos were exclusively surgical. However, by the late 1970s, most embryos were recovered and transferred nonsurgically. Successful cryopreservation of embryos was widespread by the early 1980s, followed by the introduction of embryo sp...

A commercially viable cattle embryo transfer (ET) industry was established during the early 1970s. Initially, techniques for recovering and transferring cattle embryos were exclusively surgical. However, by the late 1970s, most embryos were recovered and transferred nonsurgically. Successful cryopreservation of embryos was widespread by the early 1980s, followed by the introduction of embryo sp...

A commercially viable cattle embryo transfer (ET) industry was established during the early 1970s. Initially, techniques for recovering and transferring cattle embryos were exclusively surgical. However, by the late 1970s, most embryos were recovered and transferred nonsurgically. Successful cryopreservation of embryos was widespread by the early 1980s, followed by the introduction of embryo sp...

BACKGROUND Whether extended culture allowing selection of embryos with high development potential has any advantage over cleavage-stage embryo transfer remains a matter of debate. Among the currently unsolved questions, the cumulative delivery rate resulting from fresh and frozen embryo transfers needs to be taken into account in both strategies. The aim of our study was, therefore, to compare ...