Role of embryo morphology in Intracytoplasmic Sperm Injection cycles for prediction of pregnancy

Background: multiple factors have been suggested for prediction of pregnancy inintracytoplasmic sperm injection (icsi) cycles such as the number of injected oocytes,fertilization rate, embryo morphology and quality of transferred embryos. predictive value ofthese factors is important in icsi outcome.objectives: to evaluate the role of embryo morphology for prediction of pregnancy in icsicycles.materials and methods: this retrospective study was done on 97 patients who were treatedby icsi in fatemeh zahrafertility and infertility centre from april 2004 to march 2005.number of retrieved oocytes, number of injected oocytes, fertilization rate, zygotemorphology, rate of cytoplasmic fragmentation, number of four cell transferred embryos, andquality of embryo transfer, as predictors of pregnancy in icsi cycles were evaluated. theresults analysed by t-test, mann-whitney u test and fisher's exact test. logistic regressionwas used to estimate the significance of variables in the prediction of pregnancy probability.results: out of 97 patients, 42 cases of pregnancy were detected (pregnancy rate: 43.30/0).the number of four cell transferred embryos was 112 (53.84%) in pregnant group. pregnancyoccurred in 33 (58.9%) patients with at least one good quality zygote. the mean number offour cell transferred embryos and the quality of zygotes had significant difference betweenpregnant and not pregnant groups (p=0.006 and p=o.ooo respectively). in logistic regressionanalysis, the number of four-cell transferred embryos (p=o.007) and the quality of zygotes(p==o.003) were significant predictors of the pregnancy outcome.conclusions: our results suggest that the number of four-cell transferred embryos with :s15% cytoplasmic fragmentation and zygotes with centralized, apposed and polarizedpronuclei in women <38 years old are significant predictors for pregnancy in icsi cycles.