title: Assessment of embryo viability: the ability to select a single embryo for transfer--a review.
abstract: By being able to select the most viable embryo(s) within a given cohort it will be possible to reduce the number of embryos transferred in a given IVF procedure. Several morphological scoring systems have been proposed for the successive stages of human embryo development. Other indicators of embryo viability include rate of cleavage. Finally, non-invasive methods of assessing nutrient uptake and utilization have been developed that can be used to measure the health of individual embryos. A sequential scoring system has therefore been proposed that uses the above parameters in order to create a history for each embryo during the preimplantation period. Such systems will help lead to single embryo transfers for the majority of IVF patients.
authors.affiliation: Colorado Center for Reproductive Medicine, 799 East Hampden Avenue Suite 520, Englewood, CO 80110, USA. dgardner@colocrm.com
authors.forename: D K
authors.initials: DK
authors.lastname: Gardner
authors.forename: D
authors.initials: D
authors.lastname: Sakkas
mesh_terms: D000328:Adult; D004624:Embryo Transfer; D004622:Embryo, Mammalian / Q000502:physiology*; D005314:Embryonic and Fetal Development / Q000502:physiology*; D005260:Female; D005307:Fertilization in Vitro / Q000379:methods*; D005328:Fetal Viability / Q000502:physiology*; D006801:Humans; D011247:Pregnancy; D018873:Pregnancy Rate