Embryo Filter.

Embryo Filter.
The embryo filter has a sieve [mesh] with openings of 75 micrometers which permit fine debris, including erythrocytes (diameter 7-8 micrometers), to flow through but retains the embryos and unfertilized ova. The level of flushing medium in the filter should be maintained at no less than approximately 1 cm from the bottom to prevent the embryos from drying out on an empty screen.

Zambrano-Varon J (2012)