As a woman ages, her fertility reduces. This is mainly because the number of high-quality eggs reduces. A number of other factors like chemotherapy can also affect fertility. Thankfully, today, it is possible to preserve eggs for later use.
This is known as oocyte freezing which refers to a process wherein eggs are harvested from a woman’s ovaries, and frozen unfertilized for later use. When the woman decides that she wants to have a baby, she can thaw the eggs and use them for an IVF cycle.
Once the eggs are harvested from the ovaries, they are cooled to a sub-zero temperature. This stops all biological activity in the eggs. Cryoprotectants are then used to freeze the eggs in one of the two ways listed below:
Slow-freeze method: involves using low concentrations of cryoprotectants to gradually freeze the eggs. As the temperature reduces, the metabolic rate in the egg also reduces and the concentration of cryoprotectants is increased. This helps reduce the potential exposure of the eggs to toxins in the cryoprotectants,
Vitrification: This involves using higher concentrations of cryoprotectants to freeze the eggs rapidly. The temperature of the eggs is reduced rapidly so that there is no time for intracellular ice crystals to form.
A woman can choose to freeze her eggs if she does not want to have children right now but wants to ensure that the option to have a biological child is available to her at a later date. Since the egg is frozen in its unfertilized state, sperm is not required at this point. However, the woman will have to take some hormonal medication to stimulate the development of eggs in the ovaries.
Some of the cases in which women may want to consider Oocyte freezing are when:
Oocyte freezing could also be a boon for career-oriented women who want to have children of their own at a later date.