The aim of the present study was to investigate the number of early cleaving embryos as an effective predictor for multiple pregnancies in human in vitro fertilization (IVF).Methods
The study analyzed early cleavage (EC) in 190 cycles of IVF. The EC of embryos to the two-cell stage was assessed at two time points, namely 25 and 27 h after insemination. Embryos that had cleaved at each time point were designated EC-1 and EC-2, respectively, whereas other embryos were designated as non-EC (NEC). The number of cycles with EC-1 embryos was not included in the results for the EC-2 group.Results
Clinical pregnancy rates were significantly higher in the EC-1 group compared with the EC-2 and NEC groups (58.2%, 31.8% and 22.9%, respectively; P< 0.05). The pregnancy outcome was positively related to the number of EC-1 embryos. Multiple pregnancy rates were significantly increased up to 41.4% when the number of EC-1 embryos was two or more.Conclusions
The results confirm that 25 h after insemination is a more effective critical time point for the selection of EC embryos and that the number of EC embryos could be a useful parameter for the prediction of multiple pregnancies.