OBJECTIVE The goal of this study was to ascertain optimal assisted hatching (AH) method in frozen embryo transfer. We compared the effect of depending on whether mechanical or laser-AH was performed before or after the vitrification of embryo development rate and blastocyst cell numbers. METHODS In order to induce superovulation, pregnant mare's serum gonadotropin followed by human chorionic ...

OBJECTIVE We studied the effect of the site of laser zona opening on the complete hatching of mouse blastocysts and the cell numbers of the completely hatched blastocysts. METHODS Mouse blastocysts were randomly allocated to the inner cell mass (ICM) group (zona opening performed at the site of the ICM, n=125), the trophectoderm (TE) group (zona opening performed opposite to the ICM, n=125) a...

This report describes a live birth produced from repeat vitrification and thawing of blastocysts derived from in-vitro matured (IVM) oocytes in a woman with polycystic ovarian syndrome. Immature oocyte retrieval was performed on day 12 of her induced menstrual cycle. The patient was administered 10,000 IU of human chorionic gonadotrophin s. c. 36 h before immature oocyte retrieval. A total of 4...

BACKGROUND An estimated 3.5 million children have been born to date using assisted reproduction technologies. We reviewed the data in order to evaluate current knowledge of medical outcome for IVF/ICSI children born after cryopreservation, slow freezing and vitrification of early cleavage stage embryos, blastocysts and oocytes. METHODS A systematic review was performed. We searched the PubMed...

Enzymatic treatment of the zona pellucida to either soften or remove totally the zona before blastocyst transfer has resulted in high implantation rates. The zona is usually completely dissolved after 1.5 min exposure with 10 IU pronase at 37 degrees C. Since there may be concerns that pronase treatment for periods of 1.5 min or longer may cause adverse effects on the trophectoderm (TE) and inn...

DNA methylation is a key epigenetic mechanism responsible for gene regulation, chromatin remodeling, and genome stability, playing a fundamental role during embryonic development. The aim of this study was to determine if these epigenetic marks are associated with chromosomal aneuploidy in human blastocysts. Surplus, cryopreserved blastocysts that were donated to research with IRB consent were ...

OBJECTIVE This study was designed to investigate the survival rate of vitrified mouse blastocysts depending on the presence or absence of sucrose in vitrification solution. METHODS Mouse two-cell embryos were collected and cultured to blastocysts. Two vitrification solutions were prepared. The control solution was composed of 25% glycerol, 25% ethylene glycol, and 0.5 M sucrose (G25E250.5S) c...

During blastocyst formation the segregation of the inner cell mass (ICM) and trophectoderm is governed by the mutually antagonistic effects of the transcription factors Oct4 and Cdx2. Evidence indicates that suppression of Oct4 expression in the trophectoderm is mediated by Cdx2. Nonetheless, the underlying epigenetic modifiers required for Cdx2-dependent repression of Oct4 are largely unknown....

Background: Embryo vitrification is a key instrument in assisted reproductive technologies (ARTs). However, thereis increasing concern that vitrification adversely affects embryo development. This study intends to assess the effectof vitrification on developmental competence, in addition to expressions of long non-coding RNA (lncRNA) gene traplocus 2 (Gtl2) and its reciprocal ...

BACKGROUND The selection of pre-embryos for transferred is based on morphological appearance. But some poor quality cleaved embryos also can be cultured to the blastocyst stage and implanted. OBJECTIVE To assess the clinical pregnancy outcomes of blastocyst transfer which developed from poor quality embryos. MATERIALS AND METHODS A total of 109 cleaved embryos with poor quality were culture...