Objective. To investigate whether the perinatal risks associated with early vanishing twin (VT) syndrome differ between cleavage- or blastocyst-stage embryo transfers (ET) in fresh in vitro fertilization (IVF) cycles. Methods. Retrospective, single-center, cohort study of IVF cycles with fresh cleavage- or blastocyst-stage ETs resulting in a live singleton birth. The incidence of preterm birth ...

Lysis of the blastocyst coverings in the rabbit normally starts at the abembryonic hemisphere of the blastocyst facing the antimesometrial endometrium. Theoretically, this restricted effect could be caused by factors locally produced by abembryonic trophoblast, antimesometrial endometrium, or a combination of them. Blastocysts abnormally implanting with reversed orientation exhibit lysis of bla...

Our previous studies demonstrated that maternal (oocyte derived) follistatin (FST) expression is positively associated with bovine oocyte competence and exogenous follistatin treatment during the pre-compaction period of development (d 1-3 post insemination) is stimulatory to bovine early embryogenesis in vitro [blastocyst rates and cell numbers/allocation to trophectoderm (TE)]. In the present...

OBJECTIVE To document the risk of in vitro monochorionic dizygotic twin formation in the implementation of a program of blastocyst biopsy with preimplantation genetic screening (PGS). DESIGN Case report. SETTING Private infertility laboratory. PATIENT(S) Prospective PGS patients with intracytoplasmic sperm injection-derived, group-cultured blastocysts over a 3-year period. INTERVENTION(...

This investigation examined frozen cycle outcomes with the transfer of a single thawed blastocyst. It also aimed to determine if the suggested model could aid in achieving a better understanding of factors that influence success with frozen blastocyst transfer. A retrospective analysis was conducted of single frozen embryo transfer cycles carried out at the Cleveland Clinic Fertility Centre in ...

Transfer at the blastocyst stage has been proposed to increase the pregnancy rates after in-vitro fertilization (IVF) and embryo transfer. In the first period of experiments, culture in a single medium, from fertilization to blastocyst led to disappointing results: low blastocyst formation rates and low implantation rates per blastocyst transferred. Then the period of co-culture began (starting...

BACKGROUND In order to optimize blastocyst cryopreservation, vitrification was introduced as the routine procedure instead of slow freezing. The outcome of a closed blastocyst vitrification system was evaluated in relation to the blastocyst score before cryopreservation in single embryo transfers (SETs). METHODS Supernumerary blastocysts of IVF/ICSI patients with a fresh Day 5 transfer were v...

Retinoids are recognized as important regulators of vertebrate development, cell differentiation, and tissue function. Previous studies, performed both in vivo and in vitro, indicate that retinoids influence several reproductive events, including follicular development, oocyte maturation and early embryonic development. The present study evaluated in vitro effects of retinol addition to media c...

Embryo implantation is a highly synchronized bioprocess between an activated blastocyst and a receptive uterus. In mice, successful implantation relies on the dynamic interplay of estrogen and progesterone; however, the key mediators downstream of these hormones that act on blastocyst competency and endometrium receptivity acquisition are largely unknown. In this study, we showed that the expre...