Denudation pipettes are used in IVF laboratories to mechanically remove the remaining cumulus cells from oocytes following enzymatic treatment with hyaluronidase. This denuding step is required before ICSI, as the embryologist needs a clear view of the oocyte and access to the zona pellucida for injection. The pipette draws the oocyte through its tip, and the controlled shear force between the oocyte surface and the pipette wall strips the cumulus cells.
Internal diameter selection is the critical variable in denudation pipette choice. Too wide an internal diameter and the oocyte passes through without sufficient shear to remove the cells. Too narrow and the zona pellucida is exposed to damaging shear force that can thin or breach the zona, with potentially irreversible consequences for the oocyte. Standard internal diameters for mechanical denuding of post-hyaluronidase MII oocytes range from 135 to 160 micrometres, with the specific diameter selected based on oocyte maturity stage, zona thickness variation in the patient cohort, and individual laboratory protocol preferences established during competency development.
Cryolab supplies denudation pipettes alongside the full range of IVF micro pipettes — ICSI injection pipettes, holding pipettes, and biopsy pipettes. Contact Cryolab to discuss pipette selection for your laboratory’s ICSI and biopsy procedures.
