What is Cryopreservation? Dr. Hrishikesh Pai

If you are a person who wants to have children but wants to prioritize your education or career first, then cryopreservation is one of the best methods to ensure that you can get pregnant later in life. 

In this article, Dr. Hrishikesh Pai, one of the best IVF doctor in Nagpur will discuss the different  types and methods and some of the advantages of cryopreservation.

Read on to know more about the article,

What is cryopreservation?

Cryo – preservation is the process where cells, tissues, organelles, extracellular matrix, and organs are preserved by cooling to low temperatures.

For cryopreservation to be used with optimal success it is essential that the entire protocol of freezing, storage, and thawing procedures is carried out in the precisely required and prescribed manner.

 The team concerned with freezing must, therefore, be appropriately equipped, experienced and informed to be able to preserve the maximum viability in the frozen samples. The team responsible for the recovery of this viability, by thawing, need not be specialized in the earlier stages of cryopreservation but must be appropriately skilled and knowledgeable

Two methods of cryopreservation 

The two methods of cryopreservation are:

1. Slow freezing:

Slow freezing is a technique where the cells are cooled very slowly at around -196 C over the course of several hours. This temperature allows for the frozen eggs to be safely preserved- this temperature allows all the biological functions to stop inside the cell. This process is also called a controlled rate or slow programmable freezing.

Dr. Hrishikesh Pai, from IVF Bloom clinic, which is one among the top ten IVF hospitals in India, says that slow freezing was popular back in the mid-90s, but as of now vitrification is used as the process preserves the cells without any damage

We’ll be seeing about vitrification below,

2. Vitrification

Vitrification is the opposite of slow freezing. Vitrification is a flash freezing method in which the cells are cooled quickly in a couple of minutes. 

According to studies, vitrification is a more successful method of preserving the cells than slow freezing, as in the slow freezing method, it is likely that ice crystals will form inside the cells. Ice crystals cause damage to the cell structures, and this will make the cell unfunctional after the thawing process. 

Vitrification uses higher concentrations of cryoprotectants (chemical compounds that prevent cells or tissues from damage due to freezing) to freeze the cells faster. This will prevent the cells from being damaged.

Types of freezable tissues

The different types of freezable tissues include;

1. Egg(oocyte) freezing:

Human oocyte cryopreservation is a procedure to preserve a woman’s eggs. This technique has enabled women to postpone pregnancy to a later date – whether for medical or social reasons. 

Procedure for egg freezing

• Ovarian stimulation: your doctor will give you drugs/medications that will trigger the ovaries to produce more eggs than usual. The medicines are given two weeks before retrieving the eggs.
• Egg retrieval: The doctor will give you mild sedation and insert a transvaginal ultrasound into the vagina to locate the follicles. The doctor will place a needle to retrieve the eggs from the follicles. The doctor will extract up to 10-15 egg follicles. 
• Egg freezing: The retrieved eggs are frozen to a sub-zero temperature to store for future use.

2. Sperm freezing:

The procedure for sperm freezing is :

• Your sperm will be collected at the lab.
• The lab doctor will examine the quality and quantity of the sperm. 
• The doctor will transfer only the high-quality sperm for the cryopreservation process, where your sperm will be stored for future use.

3. Embryo cryopreservation:

High-quality embryos are frozen at sub-zero temperatures from fertilization to the blastocyst stage.

Procedure for embryo freezing

• Your doctor will give you medications to stimulate the production of eggs. This will be done 2-3 weeks before removing the eggs.
• Your doctor will retrieve the eggs from your follicle and incubate the removed eggs with sperms to fertilize them.
• The fertilized eggs are cryopreserved after three to five days of fertilization.

Advantages of cryopreservation

Dr. Hrishikesh Pai, one of the best IVF doctors in Mohali, says that cryopreservation can benefit a lot of couples.

• Delay pregnancy: The majority of women who choose to freeze their eggs prefer to put off having children until their 30s or early 40s. After 30, women’s eggs start to deteriorate in quality and quantity, making it harder to become pregnant and maintain a healthy pregnancy. Women who desire to postpone motherhood for personal reasons should save higher-quality eggs in their 20s.

• Preimplantation Genetic Testing: Women worried about passing certain genetic disorders onto their children can have embryos undergo genetic testing before they are frozen. Embryos that do not have genetic disorders can then be screened out and used for uterine implantation purposes.

• Beneficial for Women undergoing cancer treatment: Cancer therapies will negatively impact male and female fertility. Radiation and anti-cancer medications target egg and sperm cells’ DNA, which significantly lowers their viability. Cryopreservation gives women who wish to get pregnant but find out they need extensive cancer therapy the option of freezing eggs that can be used after they finish cancer treatments.
• Unused frozen embryos for multiple pregnancies: Any extra embryos can be transplanted to boost the likelihood of conception if one frozen embryo transfer doesn’t result in a pregnancy. Dr. Hrishikesh Pai, one of the best IVF doctor in Mohali says only cryopreservation offers the benefit of having numerous frozen embryos ready for usage over an extended period of time.