RESUMEN
This study is carried out to estimate the effect on embryo development and implantation potential performed by inevitably occurring short-term 3-day embryo culture condition disorders due to light microscopy applied for morphology parameter assay. One thousand two hundred and fifty-three IVF program results were analyzed to measure the pregnancy rate on embryo transfer and the percentage of embryos reached the blastocyst stage. In 58% of cases, on the 3rd day the quality of embryos was not evaluated (n = 730), while in 42% of cases the evaluation was done on day 3 (n = 523). Embryo development estimation on day 3 affects the pregnancy rate and implantation potential especially in patients of older age group. Additional embryo analysis also affects the number of blastocysts obtained. The pregnancy rate for 3rd and 5th day transfer does not differ. Additional analysis of the 3rd day embryos reduces the PR in patients of the older age group. Embryo culture condition variation has a considerable impact on obtained blastocyst number (i.e blastocyst formation) especially in patients of the older age group.