Egg Freezing

What is egg freezing?

Egg freezing is a technique that allows eggs to be stored for a long time at temperatures belowfreezing point.

Who can have egg freezing?

• Women facing medical treatment that may affect their fertility, such as chemotherapy, radiotherapy or surgical removal of the ovaries,

• Women at risk of premature ovarian failure or suffering from endometriosis, cysts and pelvic infections could preserve their fertility by storing their eggs for later use.

• Women who wish to delay having a baby, due to career demands, the lack of partner, or pathologies that momentarily prevent pregnancy, another choice in family planning.

How are the eggs collected?

1. 8-10 days of daily injections to stimulate ovaries

2. 3-4 tracking scans

3. Trigger injection

4. Egg Collection under sedation

5. Freezing of eggs

6. Not all eggs are suitable for freezing.

7. Only mature eggs will be frozen.

How are eggs frozen?

Eggs are frozen using a process known as cryopreservation, where the eggs are placed in a series of special solutions containing a cryoprotectant (antifreeze) and they are cooled very rapidly using the vitrificaiton technique. They are then placed in a storage tank containing liquid nitrogen.

How long can eggs be stored?

Eggs can, in theory, be stored for years and still be viable after thawing. Presently, the usual period for storing eggs is 10 years which can be exceeded only in certain circumstances. A written consent is required for storing eggs before treatment commences.

What happens when I want to use my frozen eggs?

Frozen eggs can be used in a natural or stimulated cycle. Once the patient is ready to proceed with treatment, the eggs are removed from storage and thawed. Not all eggs survive freezing/thawing process. Viable eggs are inseminated with sperm using a technique known as Intracytoplasmic Sperm Injection (ICSI), which has been shown to achieve better fertilisation rates with frozen/thawed eggs. Fertilised eggs are cultured for 2-3 days and the best embryo(s) are replaced in the patient’s uterus.

What are the success rates?

90-95% of eggs survive thawing. Pregnancy success rate is about 40-50% depending on sperm quality.

Are there any risks associated with egg freezing?

Current data indicate that there is no increase in birth defects or chromosomal abnormalities in children born from frozen eggs. Many healthy babies have been born following egg freezing/thawing.