The Effect of the Diameter of Aspiration Needle (17G VS 17-20G) on Oocyte Quality and Embryo’s Morpho-Kinetics - A Prospective Randomized Study on Sibling Oocyte

Introduction:

The use of 17-20G needle minimized pain and bleeding, and no effect was reported regarding the number of oocytes collected and embryos’ quality compare to 17G needle.

The aim:

Does the change in the diameter along the needle from 17 G to 20 G cause a change in the shear stress during the collection and affect the oocyte quality and embryo’s development and morpho kinetics?

Material and Methods:

A prospective randomized study. Ovaries were randomized to the aspirating needle. The embryologist was blinded to the needle. Oocyte was evaluated for 5 parameters: polar body, zona Pellucida, cytoplasm, PVS and vacuoles. Embryos were evaluating and scored by Embryo- scope.

Results:

256 oocytes were collected. Total of 118 oocytes were in the 17G group and 116 oocytes in 17-20G group.

The total negative score per oocyte was significantly higher in the 17G group compare to the 17-20G (2.20 vs. 1.3; P=0.002). No significant difference was recorded in the final morphology and the morpho kinetics of the embryos.

A presence of an abnormal or degenerative oocyte (total of 4 cycles) per cycle increased the total negative score for the oocytes and reduced fertilization rate (2.4 vs. 1.8; P=0.021 and 70.7% vs. 56.1; P=0.05).

Conclusion:

Despite the difference between the shear stress in the two different needles, the oocytes collected with 17-20G needle had lower negative score compare to the 17G needle, however it was not reflected on embryo`s morphology. Cycles with degenerative oocytes demonstrated worse oocyte quality and decreased fertilization.