OBJECTIVE To evaluate the maturation and post-thaw survival rates of immature oocytes to determine whether in vitro maturation (IVM) should be attempted prior to or after cryopreservation. DESIGN Nonrandomized observational study. SETTING Private academic and clinical reproductive center. PATIENT(S) Patients (n = 71) who donated immature unusable oocytes after vaginal oocyte retrieval (VO...

Our aim was to optimize a cryoprotectant treatment for vitrification of immature porcine cumulus-oocyte complexes (COCs). Immature COCs were vitrified either in 35% ethylene glycol (EG), 35% propylene glycol (PG) or a combination of 17.5% EG and 17.5% PG. After warming, the COCs were in vitro matured (IVM), and surviving oocytes were in vitro fertilized (IVF) and cultured. The mean survival rat...

Early frog embryogenesis depends on a maternal pool of mRNA to execute critical intercellular signalling events. FGF receptor-1, which is required for normal development, is stored as a stable, untranslated maternal mRNA transcript in the fully grown immature oocyte, but is translationally activated at meiotic maturation. We have identified a short cis-acting element in the FGF receptor 3' untr...

Genital tract abnormalities and adverse pregnancy outcome are well known in women exposed in utero to diethylstilboestrol (DES). Data about adverse reproductive performance in women exposed to DES have been published, including controversial reports of menstrual dysfunction, poor responses after ovarian stimulation, oocyte maturation and fertilization abnormalities. We compared oocyte quality, ...

OBJECTIVE To evaluate the integrity of genomic imprinting in oocytes vitrified at the germinal vesicle (GV) stage and in vitro matured (IVM) after thawing. DESIGN Clinical research and application. SETTING University-based fertility center. PATIENT(S) Immature oocytes were donated for research by patients who were included in an intracytoplasmic sperm injection program. INTERVENTION(S) ...

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...

Improvements in in vitro maturation techniques have focused on culture optimization to increase oocyte maturation rates. Specialized culture media, now commercially available, did not perform significantly better than standard IVF culture media for maturation of immature oocytes in our normal IVF cases.

BACKGROUND During the last years, several studies have reported the significant relationship between the production of soluble HLA-G molecules (sHLA-G) by 48-72 hours early embryos and an increased implantation rate in IVF protocols. As consequence, the detection of HLA-G modulation was suggested as a marker to identify the best embryos to be transferred. On the opposite, no suitable markers ar...

Cytoplasmic extracts of meiotically mature mouse oocytes were injected into immature Xenopus laevis oocytes, which underwent germinal vesicle breakdown within 2 h. Germinal vesicle breakdown was not inhibited by incubation of the Xenopus oocytes in cycloheximide (20 micrograms/ml). Identically prepared extracts of meiotically immature mouse oocytes, arrested at the germinal vesicle stage by dib...

17 Introduction 18 Ovarian stimulation 20 In vitro fertilization (IVF)/intracytoplasmic sperm injection (ICSI) 23 Immature sperm conception 25 Egg donation and surrogacy 28 Oocyte maturation 28 Embryo culture 30 Assisted hatching 31 Cryopreservation 32 Preimplantation genetic diagnosis (PGD) 34 Cytoplasmic donation and mitochondrial DNA (mDNA) transfer 37 Fertility preservation 39 Conclusion 41