EMBRYOLOGICS
Registry

Registry · technique · —

Sperm preparation — density gradient / swim-up

Separation of motile, morphologically normal sperm from seminal plasma and debris.

Clinical review pending·1 min read·Updated 2026-08-16

What it is and how it's used

Gradient lot, centrifugation parameters and time to use all influence sperm function at insemination or ICSI.

Typical failure modes

  • Reduced fertilisation after a gradient/medium lot change or altered centrifugation.
  • Poor post-prep motility; excessive processing time; temperature swings.

What to check first

  1. Post-preparation motility and concentration.
  2. Gradient/media lots and centrifuge settings.
  3. Time from production to processing to use.

IFU and practice notes

Follow the IFU of the gradient/media used; document parameters in the SOP.

Neutral, and the IFU wins

This page summarises common experience across labs and is not manufacturer guidance. Always follow the current instructions for use for the exact product and version you have, and validate any change of product or protocol before patient use. Corrections and additions are welcome — tell us.

This page is educational and general. It is not a substitute for advice from your own clinic or the manufacturer's instructions for use.