OBJECTIVE To determine the clinical potential of donor-oocyte cryopreservation and thaw techniques for recipient patients. DESIGN Institutional review board-approved prospective study of donor oocyte cryopreservation. SETTING A large, private infertility center. PATIENT(S) Four anonymous oocyte donors underwent ovarian hyperstimulation for the purpose of oocyte retrieval and cryopreservat...

Of 125 embryos (category I and II) recovered from 18 does, 25 were maintained intact as control, 25 bisected using a simplified splitting protocol, 25 frozen thawed according to a vitrification method, 25 bisected-vitrified, and 25 vitrified-bisected. The survivability of intact embryos and demiembryos were evaluated after 24 hours of in vitro culture by development ability, morphological asses...

This case illustrates the possibility of obtaining oocytes that fertilize and cleave normally after the administration of a second ovulatory dose of human chorionic gonadotrophin (HCG) in a case of 'empty follicle syndrome'. The present patient underwent ovarian stimulation with gonadotrophin-releasing hormone analogue (GnRHa)/menotropin for intracytoplasmic sperm injection (ICSI). After the fa...

The production of hydrogen peroxide (H(2)O(2)) was investigated by means of cytochemical reaction with cerium chloride in human embryos cryostoraged for a long time period. The sites of H(2)O(2) generation were demonstrated at submicroscopic level in both freshly thawed embryos and in embryos and blastocysts formed after subsequent culture. The intact blastomeres as well as cells of well develo...

background: natural endometrium in frozen-thawed embryo transfer (fet) may have some benefits upon implantation in patients with repeated implantation failure (rif). it might be due to possible differences between natural and stimulated endometrial growth factors and cytokins secretions. objective: the objective of this study was to compare the pregnancy rate of fet on modified natural cycle ve...

On a worldwide basis, more than 750,000 embryos are produced annually from superovulated donors and more than 450,000 embryos are produced using in vitro techniques. Superovulation and embryo collection are done as frequently as every 30 days. Cryopreservation and direct transfer of frozen-thawed embryos results in pregnancy rates near that of fresh embryos. Since the zona pellucida-intact in v...