How We Freeze Your Sperms


Dr. Sai, Embryologist informs you how we freeze your sperms and what are the steps involved during freezing the semen.

Dr. Sai, Embryologist, Malpani Infertility Clinic

When do we freeze sperm ?

Sperms are frozen when:

  • You are undergoing an IVF Cycle, and have difficulty producing a semen sample on demand
    ​You are not available on the day of your wife's egg collection.

  1. We also do this for young men with cancer who will be undergoing chemotherapy, so that we can preserve their fertility for the future.
  • Sperm are frozen and stored in Cans called Cryocans.
  • Cryocans contain Liquid Nitrogen to keep the sperms cold stored.

Steps Involved in Freezing Sperms:

  1. Semen Collection :

    The nurse will ask you to write your full name on a piece of paper, to avoid any spelling mistakes . This name will be written on the semen collection jar.

    This is a sterile plastic clean large mouthed jar. This is labeled with your name and the cap of the jar is labeled with your wife's name.Once the sample is collected, it arrives in the lab along with your file.The name on the file is cross checked with the one on the jar.

  2. Analysis of Semen Sample :

    Your semen sample is assessed for Volume of sample, Sperm Count, and percentage of motile sperms.

  3. Preparation of Straws to load your sperms :

    Your sperm are stored in straws. These have a capacity of 0.5ml or 0.25 ml. If we are freezing your sperms for short term period, we freeze them in 0.5ml straws. If it's a long term freeze, we freeze them in 0.25 ml straws, so that we have more straws to use.

    The straws are labeled with an ID number which will be unique for you.The ID number is generally a 6 digit number. The labeling is done corresponding to a Cm Scale as shown in the figure. This is called the French labeling system.

  4. Addition of Cryoprotectant medium :

    The sperm are delicate. To protect them from damage caused by low temperatures
    ( we freeze them at -196 C) , we add cryoprotectant medium to your sample.

  5. Loading of sperms in Straws :

    Your sperm sample is loaded into your labeled straws with the help of a syringe.

  6. Sealing of Straws :

    The loaded straws are sealed with sealing powder. Sealing powder come in different
    colors. For freezing different patient's sperms we use different colored powder for
    sealing. This colour coding helps us to identify samples with ease.

  7. Storage of your Straws in Cryocans :

    Once your straws are sealed, they are placed in visitube. Visitubes come in different
    Colors as well. Different colored visitubes are used for different patients.

    The sperm are frozen in stages. Initially, the visitube with all your straws is kept in liquid nitrogen vapours for 15 min. After this, they are then plunged into liquid nitrogen, where they are safe and secure, because all metabolic activity is suspended. They will remain here until we are ready to use them , at which point we will identify your sample; remove a single straw; and thaw it. The sperm will regain their motility once they are 37 C. About 50% of sperm will die as a result of this process.
  8. Identification for your sperms :

    Your sperms will be identified by -
    1. Canister number of cryocan
    2. Color of visitube
    3. Color of straws
    4. ID number on straws

Your Sperms

Loaded into Labelled Straws

Straws are kept in Visitubes

Visitubes are kept in Canisters



The Sperm freezing procedure is a very complex one and involves a number of steps. Experts at the Malpani Infertility Clinic handle this job expertly and meticulously.

Authored by : Dr Aniruddha Malpani, MD and reviewed by Dr Anjali Malpani.