Human oocyte oolemma characteristic is positively related to embryo developmental competence after ICSI procedure

AimThe aim of this study was to analyse the correlation between various reactions displayed by the oolemma to the penetrating pipette during intracytoplasmic sperm injection (ICSI) and embryo developmental competence after ICSI procedure.Materials and methodsThe injected metaphase II (MII) oocytes which showed different responses to the injection pipette were classified into three groups (100 oocytes each) according to types of oolemma responses. Group 1: no resistance breakage, Group 2: (curve shape) mild resistance, Group 3: (funnel shape) good resistance.ResultsThe results showed that classification based on oolemma behavior during ICSI procedure (Groups 1–3) indicates a significant correlation with fertilization rate (2PN) (55%, 87% and 72%, respectively P<0.01) and cleavage rate (75%, 96% and 79%, respectively P<0.01) and embryo quality (4–8 cells Grade 1 embryo) (50%, 90% and 70%, respectively P<0.001).ConclusionThe current study provides evidence that preselection at a very early stage based on oolemma behavior may be helpful to identify a subgroup of preimplantation embryos with good prognostic to form blastocyst and consequently to implant and to give pregnancy.