World Embryologist Day: Celebrating a Crucial Role

On July 25, 1978, Louis Joy Brown became the first baby to be successfully conceived through the in vitro fertilization (IVF) method. This groundbreaking achievement in reproductive medicine changed the world, allowing intended parents struggling with infertility to grow their families. Brown’s birthday is now celebrated every year as World Embryologist Day.

In honor of World Embryologist Day, we want to highlight all the important work embryologists do behind the scenes, handling delicate embryos and ensuring their successful development, especially regarding frozen donor eggs. In this blog, we sat down with Jennifer Hart, M.S., T.S. (ABB), Director of Embryology Relations at Fairfax EggBank, to learn more about the crucial role embryologists play in the frozen donor egg process.

What is an embryologist?

An embryologist is the scientist in the laboratory at the IVF clinic that identifies and fertilizes the eggs in the laboratory. He/she is responsible for maintaining a specific environment for the eggs and embryos so they can develop in culture.

Eggs will be frozen or fertilized on the same day as the egg retrieval. Embryos will be cultured for up to 7 days after fertilization and the embryologist will either transfer or biopsy and/or freeze the embryos. A lot goes into maintaining the environment and manipulating the eggs/embryos, which is why embryologists are a lot like the Wizard of Oz – the magicians behind the curtain.

What is an embryologist responsible for in the frozen donor egg process?

The embryologist is a key player in any IVF clinic. When it comes to frozen donor eggs, the embryologist must prepare culture media and supplies for the thaw procedure the day before to ensure everything is at the correct temperature and pH. He/she will remove one device of donor oocytes at a time and follow the specific protocols set forth by the donor egg bank.

These protocols involve moving the oocytes through different solutions until they finally rest in culture media for a couple hours before attempting fertilization.

How are eggs warmed?

Frozen eggs can be stored on different devices. The most common devices used in the US are cyrotops and cryolocks. These devices look like short straws and will each generally hold 1-2 mature donor oocytes. It is very important that the devices stay submerged in liquid nitrogen until they are ready to be warmed.

Cryotops used to store Frozen Eggs

Cryolocks used to store Frozen Eggs

The embryologist will remove one device at a time. It is very important to move the device directly from the liquid nitrogen into a warm culture dish with a thawing solution that is at 37 degrees Celsius (body temperature). This transition must happen within milliseconds.

Once the eggs are warmed in this first solution, they will be moved to different solutions to transition the eggs from the special solution they were frozen in and replace it with culture media that can provide the nutrients the eggs need to recover from the vitrification and warming process.

What role do embryologists play in the egg retrieval process?

As the physician is in the egg retrieval, he/she will use a needle to drain the fluid in the follicles. The fluid will be put in tubes and passed into the lab.

The embryologist will pour the tubes into dishes in the lab so he/she can search through the fluid to find the eggs. Once all the eggs are collected, the embryologist will remove the cloud of (cumulus) cells surrounding the eggs so maturity can be assessed. They will then be placed in culture until fertilization or cryopreservation.

What are your favorite parts about your role as an embryologist at Fairfax EggBank?

Being an embryologist at Fairfax EggBank is unique because it allows me to collaborate with embryologists all over the world and not only share the knowledge I’ve gained over my 22 years in the IVF lab, but also learn how others are doing things in the lab. One of the things I love about being in the field of infertility is that everyone is very collaborative, and it allows us to learn from each other. Ultimately, our patients benefit from that exchange of knowledge.

Learn more about the author

Jennifer Hart, M.S., T.S. (ABB)

Jennifer Hart, M.S., T.S. (ABB), is the Director of Embryology Relations at Fairfax EggBank. With over 20 years of IVF laboratory experience, Jennifer is passionate about advancing the field of embryology. Originally from Chicago, Jennifer earned her bachelor’s degree from the University of Illinois in 2001 and her master’s degree in Clinical Embryology and Andrology from Eastern Virginia Medical School in 2006. She is certified by the American Board of Bioanalysts (ABB) as a Technical Supervisor in both Embryology and Andrology. Jennifer relocated to the St. Louis area in 2002, shortly after beginning her career in the field of infertility. She founded and currently spearheads the St. Louis Area Reproductive Society that meets quarterly to provide education and career development connections for IVF laboratory staff and physicians.