Egg freezing is a revolutionary technology in reproductive medicine that allows long-term preservation of female gametes at extremely low temperatures. This innovative process offers women the ability to preserve their fertility for future use.
Egg Freezing and In Vitro Fertilization
What is Egg Freezing?
Cryopreservation technology is based on the principle of ultra-cooling, where eggs are preserved in liquid nitrogen at -196 degrees Celsius. At this temperature, all biological processes stop completely, allowing long-term cell preservation without loss of viability.
Historical Evolution of Cryopreservation
Egg cryopreservation was initially developed for medical reasons, mainly for women facing cancer treatments that could affect their fertility. Today, applications have expanded significantly, covering both medical and social indications.
When is Egg Freezing Recommended?
Medical Indications
Egg cryopreservation is recommended in various medical conditions that may affect fertility:
- Cancer Treatments: Chemotherapy and radiotherapy can destroy eggs, leading to premature menopause. Cryopreservation offers the opportunity to preserve fertility before treatment begins.
- Autoimmune Diseases: Certain autoimmune conditions and their treatments may affect ovarian function. Timely cryopreservation can ensure future reproductive capabilities.
- Genetic Disorders: Women with genetic disorders leading to premature ovarian failure may benefit from timely egg cryopreservation.
Social Indications
In modern society, cryopreservation for social reasons is becoming increasingly popular. Many women choose to postpone motherhood to achieve their professional goals. Cryopreservation offers them freedom of choice for the right timing.
The Egg Freezing Process
Preliminary Assessment
Before starting the process, complete assessment of the woman's reproductive health is necessary. This includes:
- Hormonal Tests: Measurement of AMH (Anti-Müllerian Hormone), FSH, LH, and estradiol levels to assess the ovarian reserve.
- Ultrasound Examination: Ovarian assessment and follicle measurement to estimate the number of the available eggs.
- Medical History: Detailed recording of medical and reproductive history to estimate the success probabilities.
Ovarian Stimulation
The process begins with ovarian stimulation, where hormonal medications are used for multiple egg development:
- Stimulation Protocols: Different protocols are used depending on the age, the ovarian reserve, and the patient characteristics.
- Monitoring: Regular ultrasound examinations and hormonal measurements to monitor follicle development.
- Timeline: Stimulation usually lasts 10-14 days, with final maturation injection 36 hours before the retrieval.
Egg Retrieval
Egg retrieval is a minor surgical procedure performed under ultrasound guidance:
- Procedure: A special needle is used to retrieve eggs from the ovaries through the vagina.
- Anesthesia: The procedure is usually performed under mild sedation or local anesthesia.
- Duration: Retrieval lasts approximately 10-20 minutes, depending on the number of follicles.
Laboratory Processing and Cryopreservation
Immediately after the retrieval, eggs undergo laboratory processing:
- Egg Assessment: Each egg is examined for its maturity and viability.
- Cryopreservation Preparation: Mature eggs are prepared with special cryoprotective substances.
- Vitrification Process: The vitrification technique is used which achieves higher survival rates compared to older methods.
In Vitro Fertilization (IVF) with Cryopreserved Eggs
Thawing and Preparation
When a woman decides to use her cryopreserved eggs, the process begins with thawing:
- Thawing Process: Eggs are gradually thawed with a special protocol ensuring maximum survival.
- Viability Assessment: Each egg is examined for the preservation of the structure and the functionality.
- Survival Rates: Modern protocols achieve survival rates above 90% for eggs cryopreserved with the vitrification method.
- Fertilization Process
After successful thawing, eggs undergo fertilization:
- Intracytoplasmic Sperm Injection (ICSI): The preferred method for cryopreserved eggs, as it ensures higher fertilization rates.
- Traditional IVF: Can also be used, especially when sperm characteristics are excellent.
- Embryo Culture: Fertilized eggs are cultured in the laboratory for 3-5 days before the transfer.
Embryo Transfer
Embryo transfer is the final stage of the process:
- Endometrial Preparation: The uterus is prepared with hormonal therapy in order to be receptive to the transfer.
- Embryo Selection: Embryos with the best quality are selected for transfer.
- Transfer Procedure: This is a simple procedure that does not require anesthesia.
Success Rates and Influencing Factors
Success Factors
Success rates of the egg cryopreservation and subsequent the IVF depend on various factors:
- Cryopreservation Age: The age at which cryopreservation occurs is the most important factor. Women under 35 years have the best results.
- Egg Quantity and Quality: The number of cryopreserved eggs and their quality directly affects the success probabilities.
- Cryopreservation Technology: Use of modern techniques like vitrification, significantly improves the results.
Success Statistics
According to the most recent data, success rates show encouraging trends:
- Egg Survival: Over 90% of eggs cryopreserved with modern methods survive the thawing process.
- Fertilization Rates: 70-80% of surviving eggs fertilize successfully.
- Pregnancy Rates: Pregnancy rates per cycle range from 30-60%, depending on the age and other factors.
Future Developments and Innovations
Technological Advances
The science of cryopreservation continues to evolve:
- Improved Techniques: New cryopreservation methods promise even higher survival rates.
- Artificial Intelligence: Use of AI to improve egg selection and assessment.
- Regenerative Medicine: Research for creating eggs from stem cells.
Conclusions
Egg cryopreservation and in vitro fertilization offer women unprecedented capabilities for controlling their reproductive health and motherhood timeline.
Despite challenges related to cost, ethical issues, and technology limitations, the benefits are significant. For women facing medical conditions threatening fertility, cryopreservation can be the hope for future motherhood. For others, it offers the flexibility to align their reproductive choices with their personal and professional goals.
The continuous evolution of technology, improvement of success rates, and increasing accessibility promise that these treatments will become even more effective and available in the future. It is important for women to be fully informed about their options and work closely with specialists in reproductive medicine to make the best possible decisions for their reproductive health.
Kostis Nikolopoulos stands by you with understanding and specialized guidance.