Introduction to Egg Freezing

Learning Objectives:

Upon completion, you will understand:

• The fundamental science behind egg freezing and why it’s a viable option today.
• The step-by-step medical process, from initial consultation to egg retrieval.
• The critical factors that influence success, particularly the impact of age.
• How to interpret success rate data and cost considerations.

The Science & Purpose of Egg Freezing

What is Elective Egg Freezing?

Elective, or social, egg freezing is a proactive medical procedure where a woman’s eggs are retrieved, frozen, and stored for future use. The primary goal is to preserve a woman’s current reproductive potential, effectively “pausing” the biological clock. This allows individuals to pursue personal, educational, or career goals without the pressure of declining fertility.

The Biological Imperative: Why Age Matters

A female is born with her entire lifetime supply of eggs. This pool of eggs decreases in quantity and, most importantly, quality over time. The decline becomes more significant after age 35. This impacts two key areas:

1. Probability of Conception: The chance of getting pregnant naturally decreases each year.
2. Probability of a Healthy Pregnancy: The risk of chromosomal abnormalities (e.g., Down syndrome) increases with maternal age.

Egg freezing circumvents this by preserving younger, healthier eggs for use later in life.

The Technology: Vitrification

The breakthrough that made egg freezing a mainstream success is a rapid-freezing technique called Vitrification. Unlike the slow-freezing methods of the past, vitrification uses high concentrations of cryoprotectants and extremely fast cooling rates to solidify the egg into a glass-like state without forming damaging ice crystals. This has dramatically improved post-thaw survival, fertilization, and pregnancy rates.

The Medical Process: A Step-by-Step Guide

Step 1: Initial Consultation & Ovarian Reserve Testing

The journey begins with a comprehensive evaluation.

• Medical History & Counseling: We discuss your personal goals, medical history, and ensure you have realistic expectations.
• Ovarian Reserve Testing: This involves a blood test (typically for Anti-Müllerian Hormone or AMH) and a transvaginal ultrasound (to perform an Antral Follicle Count or AFC). These tests help us estimate your ovarian response to medication and tailor your protocol.

Step 2: Ovarian Stimulation

For approximately 8-14 days, you will self-administer daily hormonal injections.

• Purpose: To stimulate the ovaries to develop multiple mature eggs in a single cycle, rather than the single egg typically ovulated each month.
• Monitoring: You will visit the clinic frequently for blood tests and ultrasounds to monitor follicle growth and adjust medication dosages as needed for optimal results and safety.

Step 3: Trigger Shot & Egg Retrieval

• Trigger Shot: Once the follicles reach an optimal size, a final “trigger” injection of hCG or Lupron is administered to finalize egg maturation.
• Egg Retrieval: Approximately 36 hours after the trigger, the eggs are retrieved. This is a minor surgical procedure performed under light sedation or anesthesia. Using an ultrasound-guided needle, the fluid from each follicle is aspirated. The procedure typically takes 20-30 minutes.

Step 4: Laboratory & Cryopreservation

The retrieved fluid is immediately examined by our embryologists under a microscope. The mature eggs (Metaphase II) are identified, prepared, and vitrified (flash-frozen) for long-term storage in specialized cryogenic tanks.

Success Rates & Realistic Expectations

Interpreting the Data

It is crucial to understand that success is not guaranteed by the act of freezing alone. The ultimate goal is a live birth, which is a multi-step process with cumulative success rates at each stage.

Key Variables Influencing Success:

1. Age at Freezing: This is the single most important factor. Eggs frozen at a younger age (e.g., under 35) have a significantly higher potential for resulting in a live birth.
2. Number of Eggs Frozen: We generally recommend freezing 15-20 mature eggs to maximize the chance of one live birth. The number of eggs retrieved per cycle is directly tied to your age and ovarian reserve.
3. Clinic & Laboratory Expertise: The success of an egg freezing cycle is heavily dependent on the skill of the medical team and the quality of the embryology lab.

The “Thaw to Baby” Journey:
When you are ready to use your eggs, they will be thawed, fertilized with sperm via ICSI (Intracytoplasmic Sperm Injection), and the resulting viable embryos will be transferred to the uterus. Success rates are typically quoted as the live birth rate per thawed egg or per embryo transfer.

Financial, Legal, and Ethical Considerations

Cost Breakdown

Egg freezing involves significant financial investment, which can be broken down into:

• Initial Cycle Costs: Medications, monitoring, retrieval procedure, and anesthesia.
• Annual Storage Fees: For maintaining the frozen eggs in the cryogenic facility.
• Future Thaw & Fertilization Costs: Not included in the initial freeze and incurred when you decide to use the eggs.

Legal & Ethical Framework

• Storage Limits: Be aware of the legal time limits for storing eggs in your jurisdiction.
• Disposition of Eggs: It is essential to have a signed consent form outlining your wishes for the eggs in unforeseen circumstances (e.g., death, decision to no longer store them).
• Clinic Responsibility: Understand the clinic’s policies regarding tank failures or other catastrophic events.