PI moved from Hadassah

Selecting one or two IVF embryos with the highest potential to implant is extremely important for the success of the treatment- obtaining pregnancies and avoiding multi-fetal gestations. The currently used IVF embryo grading method is based solely on embryo morphology (cleavage rate and fragmentation) just before the transfer, which is not very well correlated with the implantation potential of each embryo. Oocyte quality and adequacy are the most important factors determining the biological quality and implantation potential of the embryo. It impossible to grade oocytes using plain optical systems, other than maturity and gross anomalies.

Polscope systems allow to visualize intra ooplasmic structures and determine their retardance, as well as that of the Zona Pellucida. The investigators hypothesize that grading embryos using the oocyte's parameters as visualized by polscope is superior to conventional morphology and correlates better with their implantation potential.

Here the investigators will perform a prospective randomized controlled trial to examine this hypothesis.

Each embryo will be graded in accordance to polscope based parameters; the presence of a spindle in the oocyte, its retardance, the distance between the spindle and the PB, and the thickness and retardance of the ZP.

In the experimental group the embryos for transfer will be selected based on these parameters, whereas in the control group they will be selected based on conventional morphologic criteria.

Inclusion Criteria:

• Age 18-38, (near) normal MF, normal uterus, >4 aspirated oocytes, intent to transfer 1-2 embryos.

Exclusion Criteria:

• Severe MF problems, uterine anomalies, PGD, RIF.