Abstract
The aim of this study is to compare blastocyst development and cycle outcomes of good prognosis elective single embryo transfer patients using conventional or time lapse incubators. A randomized study was designed to evaluate embryo development until the blastocyst stage in either conventional or time-lapse incubators in good prognosis patients. Furthermore cycle outcomes of the patients were evaluated. The study involved 64 patients (33 for time-lapse and 31 for conventional incubation) in their first or second treatment cycle, with no recurrent spontaneous miscarriages, age<35 years, body mass index <28 kg/m2 and ≥8 oocytes retrieved. The primary outcome was the proportion of good and top quality blastocysts on day 5 and the secondary outcome was the implantation and pregnancy rates after elective single embryo transfer in good prognosis patients. The analysis performed revealed no statistical difference between both groups for blastocyst development, implantation and clinical pregnancy rates. In a selected good prognosis elective single embryo transfer population, similar rates of good and top quality blastocysts and comparable implantation and pregnancy rates were achieved. However, the stable culture conditions provided by time-lapse incubators and the use of morphokinetic parameters may allow the selection of the best available embryos with high developmental capacity, especially in poor prognosis patients.