About Hyaluronic Mature Sperm Selection Method (Sperm Slow™)

Hyaluronic Mature Sperm Selection Method is a sperm immobilizing medium that was developed in order to have ICSI be carried out naturally.
This medium’s base is hyaluronic acid.
Hyaluronic acid is the main component of zona pellucida in oocyte cumulus cells and oocytes, and mature sperm retains receptors attached to hyaluronic acid.
In contrast, immature sperm do not retain attached receptors.
In the original fertilization process only mature sperm adheres to the zona pellucida of the ovum, and fertilization occurs through it.
Sperm in good condition and less likely to have chromosomal abnormalities are selected by this method.

By regular ICSI, sperm is selected by motility and formation.
However, by only visually selecting, sperm having DNA damage is not known, and the risk of abnormal fertilization by chromosomal abnormalities cannot be avoided.
Hyaluronic acid mature sperm selection method is selecting mature sperm after using the ability of only allowing mature sperm to adhere with hyaluronic acid.


Although we cannot guarantee the out came, research shows this method helps to significantly improved embryo quality and development, reducing pregnancy loss.


There is no invasive damage to the sperm by this method, but because it does take time to select the sperm there is concern about harmful effects (decrease of sperm motility rate and motility).