Abstract
Over the past 20 years, numerous techniques have enhanced assisted reproductive technology
outcomes to help couples have >60,000 infants in the United States in 2008. Several
different days for embryo transfers have been studied, but debate for the best timing
of embryo transfer is still ongoing. With growing concern about multiple gestations
and neonatal outcomes, early cleavage stage embryo transfer with novel embryo selection
tools may be attractive to some patients and in vitro fertilization programs. In this
review, we summarize clinical and basic studies relating to the timing of embryo transfer
and highlight the possibilities of safe embryo transfer by combining advanced embryo
screening tools with potentially high efficiency and low adverse effects on clinical
outcome.
Keywords
day 2 embryo transfer - assisted reproductive technology - time-lapse imaging - embryo
selection