Total fertilization success and embryo formation in ART treatments; does it have any predictive value?

This retrospective study was aimed to investigate the characteristics of cycles with 100% achievement in laboratory procedures to determine the predictors of cycles with total fertilization success (TFS) and following total embryo formation (TEF). 273 ART cycles were categorized into two groups of the case (n= 121) and control (n=152). Inclusion criteria for case group were; cycles that a total number of MII oocytes were fertilized, and a total of fertilized oocytes developed into the embryos. Demographic variables, ART cycle characteristics and clinical outcomes were assessed and compared between groups. In subcategorizing, the case group was divided into two groups; A) patients with five or fewer (≤5) MII oocytes (n=94); B) patients with more than five (>5) MII oocytes (n=27). Clinical outcomes were assessed between subgroups of A, B and control. Man-Whitney U test, independent sample test and chi-square test were applied wherever appropriate to compare between two groups. P-value less than 0.5 were considered significant. Serum levels of E2, number of COCs, MII oocytes and transferred embryos differed between the groups (P< 0.0001 and P= 0.001). There was a trend manner in increasing the rate of ICSI in case group rather than controls (76.9% vs. 67.1%, respectively; P= 0.081). Furthermore, data sub-analysis showed that the rates of good quality embryos, chemical and clinical pregnancies were higher in subgroup B rather than the other subgroup; however, the differences were not significant (P= 0.07, 0.71 and 0.07, respectively). To increase the likelihood of a successful pregnancy in ART cycles, higher good quality embryos and appropriate number of available embryos for transfer could play an important role.