Sperm cryopreservation requires a dedicated equipment set within the broader IVF lab infrastructure. Here is what a UK fertility clinic needs to run a compliant sperm freezing programme.
A controlled rate freezer is used to reduce the sperm sample temperature in a programmed, gradual manner before final plunge into liquid nitrogen. Some clinics use vapour phase freezing as an alternative, lowering samples above a liquid nitrogen surface before immersion, but controlled rate freezing provides more reproducible results for high volume programmes.
Cryoprotectant media such as glycerol based extenders are required to protect sperm cells from ice crystal damage during the freezing process. These are mixed with the sperm sample at a specific ratio before loading.
Storage straws or cryovials are used to contain individual patient samples. Straws are the more common format for sperm storage as they allow efficient use of dewar space and straightforward sample retrieval.
Liquid nitrogen storage tanks and appropriate internal rack systems are required for long term storage. A dedicated sperm storage dewar separate from embryo storage is best practice for sample segregation.
Cryogenic labelling is essential at every step. Each straw or vial must be permanently labelled with patient identification that survives liquid nitrogen immersion indefinitely. Purpose built cryogenic markers rated for minus 196 degrees Celsius are non-negotiable for this. Standard permanent markers will fail. Cryolab.co.uk supplies cryogenic markers, storage straws, labels and liquid nitrogen equipment for UK sperm cryopreservation programmes.
