What is Embryo Freezing?

Embryo Freezing

Embryo freezing, also known as embryo cryopreservation, is a revolutionary technique that has transformed the landscape of assisted reproductive technology (ART). This process allows couples struggling with infertility to preserve viable embryos for future use, giving them hope for a successful pregnancy. While embryo freezing has numerous advantages, it is crucial to acknowledge and understand the potential demerits, such as the association with hypertension during pregnancy when using frozen embryos. In this blog, we will explore the embryo freezing process, the benefits, and the risks associated with this procedure, including hypertension during pregnancy.

How does Embryo Freezing Work?

Embryo freezing involves a multiple-step process, it starts with ovarian stimulation to produce multiple eggs. These eggs are then retrieved, and fertilized with sperm, leading to the creation of embryos. The developed embryos are then evaluated for quality, and the healthiest ones are selected for freezing. These embryos are preserved in liquid nitrogen at extremely low temperatures, effectively putting them in a state of suspended animation until they are ready for transfer.


What are Some of the Benefits of Using Embryo Freezing?

  • Increased Success Rates: One of the most significant advantages of embryo freezing is its potential to increase the success rates of in vitro fertilization (IVF) cycles. By freezing high-quality embryos, couples can undergo multiple transfer attempts without the need for additional egg retrieval procedures. 
  • Time Flexibility: Embryo freezing provides flexibility in planning embryo transfer. This allows couples to align the transfer with the most suitable time for implantation, increasing the chances of a successful pregnancy.
  • Genetic Testing: The process of embryo freezing allows for preimplantation genetic testing (PGT), which enables the screening of embryos for genetic abnormalities before transfer. This helps reduce the risk of passing on certain genetic disorders to the offspring.
  • Family Planning: Embryo freezing offers couples to preserve surplus embryos for future family planning. This is particularly helpful for couples facing medical treatments that may impact their fertility or those who wish to have more children at a later stage.

What are the Disadvantages of Embryos Freezing?

  • Hypertension during Pregnancy: Recent research has indicated a potential association between embryo freezing and an increased risk of hypertension during pregnancy. A study published in the “Journal of the American College of Cardiology” found that pregnancies conceived through the use of frozen embryos had a higher likelihood of developing gestational hypertension compared to pregnancies from fresh embryos. However, further research is needed to establish a definitive causal link between embryo freezing and hypertension.
  • High Costs: The process of embryo freezing, along with ongoing storage fees, can impose significant financial burdens on couples. This can become a barrier for those with limited financial resources to access ART treatments.
  • Ethical Concerns: Embryo freezing raises ethical dilemmas, as some individuals and groups consider frozen embryos as potential life forms. Decisions about what to do with unused embryos and the moral implications of discarding them can be emotionally challenging for couples.
  • Limited Shelf Life: Embryo freezing can extend the shelf life of embryos, but there is no assurance of their viability once thawed. The freezing and thawing process may not be successful for all embryos, which could decrease the number of viable embryos available for transfer in the future. Additionally, storage is a crucial factor to consider.
  • Storage Risks: Despite advances in cryopreservation techniques, there remains a small risk of storage failure, which could result in the loss of all stored embryos. This can be devastating for couples who were banking on these embryos for their future family planning.


Embryo freezing is an invaluable tool in the world of assisted reproductive technology, offering hope to countless couples struggling with infertility. The advantages of this procedure, such as increased success rates, genetic testing, and family planning, are undeniable. However, it is essential to be aware of the potential demerits, including the association with hypertension during pregnancy when using frozen embryos.

While research continues to shed light on the risks, it is crucial for couples to have candid discussions with their healthcare providers and weigh the benefits and drawbacks carefully. Each couple’s journey is unique, and it is vital to make informed decisions that align with their values, beliefs, and medical circumstances. Embryo freezing can be a promising option for many, but it is essential to navigate its risks responsibly and with care.