Receptivity is a limited time in which uterine endometrium can establish a successful dialogue with blastocyst. This study was to investigate the effect of asynchronous embryo transfer on uterine receptivity in mice. Embryos under different stages were transferred into two oviduct sides of a recipient mouse on day 1 of pseudopregnancy. Our results showed the asynchronously transferred embryos c...

BACKGROUND Multiple pregnancies are one of the major safety concerns of in vitro fertilization (IVF) due to the increased risk of maternal and neonatal complications. Single embryo transfer is the most effective way to reduce the risk of multiple pregnancies. Selection of the embryo and optimization of the implantation environment are crucial to retain the success rate when the number of transf...

OBJECTIVE To evaluate the effect of hyaluronan-rich transfer medium on pregnancy and implantation rates in fresh and frozen-thawed embryo transfers in Korean women with previous implantation failure. METHODS This retrospective study included 283 blastocyst transfers in patients with previous embryo transfer failure at a private fertility clinic. In the study group (n=88), blastocyst transfers...

OBJECTIVE To investigate the single blastocyst transfer in preimplantation genetic diagnosis (PGD)/preimplantation genetic screening (PGS) cycles. METHODS 80 PGD/PGS cycles undergoing blastocyst biopsy were studied. There were 88 warming cycles during the study period. Only one warmed blastocyst was transferred per cycle. The outcomes were followed up to the infants were born. RESULTS The e...

STUDY QUESTION What are the clinical efficacy and perinatal outcomes following transfer of vitrified blastocysts compared with transfer of fresh or of slow frozen blastocysts? SUMMARY ANSWER Compared with slow frozen blastocysts, vitrified blastocysts resulted in significantly higher clinical pregnancy and live delivery rates with similar perinatal outcomes at population level. WHAT IS KNOW...

It should now be beyond doubt that blastocyst culture results in better pregnancy rate (PR). This calls for fewer embryos to be transferred, and indeed blastocyst culture is of most value when the intention is to put back one embryo at a time. The PR with one top-grade blastocyst is 45-65% in different studies. If two top-grade blastocysts are transferred, the PR usually does not differ, but th...

OBJECTIVE To study the clinical outcomes of single frozen-thawed blastocyst transfer cycles according to the hatching status of frozen-thawed blastocysts. METHODS Frozen-thawed blastocysts were divided into three groups according to their hatching status as follows: less-than-expanded blastocyst (≤EdB), hatching blastocyst (HgB), and hatched blastocyst (HdB). The female age and infertility fa...

BACKGROUND Several studies have evaluated outcomes of singleton pregnancies after blastocyst versus cleavage stage embryo transfer. Higher incidences of preterm birth (PTB), very preterm birth (VPTB), low birthweight (LBW) and congenital malformations were identified in a few of them. The objective of our study was to systematically review and meta-analyze pregnancy and neonatal outcomes among ...

Background: In contrast to animal data, group culture does not increase preimplantation development in humans. This prospective study was done to test a new type of culture dish allowing for individual culture and any possible effect of autotrophic factors. Materials and Methods: Within a 6-month period, 72patients with ≥9 fertilized eggs were enrolled in this prospective evaluation. Their 936 ...