Step-by-Step process of embryo freezing in an IVF cycle

1. Egg retrieval (Ovum Pick-Up)

• Around 36 hours after the trigger shot, eggs are retrieved through a minor surgical procedure.
• The process is conducted under mild sedation or anesthesia to ensure patient comfort.
• A thin needle is inserted into the ovarian follicles to aspirate (suction out) the eggs.

2. Fertilization in the laboratory

• Retrieved eggs are combined with sperm to facilitate fertilization.
• There are two main methods:
• Conventional IVF: The egg and sperm are placed together in a petri dish for natural fertilization.
• Intracytoplasmic Sperm Injection (ICSI): A single healthy sperm is injected directly into the egg, typically used for male infertility cases.
• Fertilization success is assessed after 16-18 hours.

• Conventional IVF: The egg and sperm are placed together in a petri dish for natural fertilization.
• Intracytoplasmic Sperm Injection (ICSI): A single healthy sperm is injected directly into the egg, typically used for male infertility cases.

3. Embryo culture and Selection

• Fertilized embryos are cultured in a specialized incubator for 3 to 5 days.
• Embryologists monitor cell division and growth to identify high-quality embryos.
• The embryos reach the blastocyst stage (Day 5 or 6), which has a higher implantation success rate.
• Only the best-quality embryos are selected for freezing to maximize the chances of pregnancy.

4. Embryo freezing using vitrification

• The selected embryos undergo a rapid freezing process called vitrification, which prevents the formation of damaging ice crystals.
• Steps involved in vitrification: Embryos are treated with cryoprotectants, substances that protect them from ice formation. The embryos are then rapidly cooled to -196°C using liquid nitrogen. They are stored in specialized cryogenic storage containers.

• Embryos are treated with cryoprotectants, substances that protect them from ice formation.
• The embryos are then rapidly cooled to -196°C using liquid nitrogen.
• They are stored in specialized cryogenic storage containers.

5. Long-Term storage in cryo-tanks

• The frozen embryos are carefully stored in liquid nitrogen tanks at sub-zero temperatures.
• Embryos can remain frozen for several years without losing their viability.
• Patients can choose to use them for future IVF cycles or donate them for research.

6. Thawing and Embryo transfer

• When a patient is ready to conceive, the frozen embryos are thawed for transfer.
• The thawing process involves carefully warming the embryos and removing the cryoprotectants.
• Embryologists assess the viability of the embryos before transferring them into the uterus.
• The embryo transfer is a simple, painless procedure, and pregnancy is confirmed through a beta hCG test after 10-14 days.

Success rates of embryo freezing

• The success rate of frozen embryo transfers (FET) is comparable to or even higher than fresh embryo transfers.
• Vitrified embryos have a survival rate of 95-98%, ensuring excellent pregnancy outcomes.
• The chance of pregnancy depends on factors like embryo quality, uterine receptivity, and overall patient health.

Who can benefit from embryo freezing?

• Couples undergoing IVF: Those who produce multiple viable embryos can freeze excess embryos for future attempts.
• Women delaying pregnancy: Individuals who wish to postpone childbirth due to career, personal, or medical reasons.
• Patients with recurrent IVF failures: Freezing allows multiple embryo transfers without repeating ovarian stimulation.
• Cancer patients: Women diagnosed with cancer can preserve embryos before undergoing chemotherapy or radiation.

Risks and Considerations

While embryo freezing is a safe and widely used technique, there are some factors to consider:

• Not all embryos survive the freezing and thawing process.
• The success of future pregnancies depends on the quality of the embryos.
• Some women may require additional uterine preparation before undergoing frozen embryo transfer.

Conclusion

Embryo freezing is a game-changer in reproductive medicine, offering flexibility, cost savings, and improved success rates for IVF patients. By preserving high-quality embryos, individuals can enhance their chances of pregnancy while reducing the physical, emotional, and financial burden of undergoing multiple IVF cycles. This advanced technique provides hope for those planning future pregnancies, facing medical treatments that may impact fertility, or seeking to optimize their IVF outcomes. Contact Bavishi Fertility Institute today to explore your options and take the next step toward a successful pregnancy.

For personalised advice tailored to your test results and diagnosis, book a consultation with our specialists at Bavishi Fertility Institute.