History

The first baby born from a frozen egg (oocyte) was back in 1986. This means oocyte cryopreservation (egg freezing) has been around for a long time. But up until 2012, the American Society of Reproductive Medicine (ASRM) considered egg freezing to be experimental. Why is that? Well up until 2012, eggs were frozen via a slow freeze technology, and only about half of eggs would survive when thawed. With time and advancements in the lab, a new technology called vitrification emerged. This is a form of rapid or flash freezing of eggs, and has improved the survival of eggs when thawed. With vitrification, about 85% of eggs survive when thawed.

The Biological Clock

The biological clock is real. Women lose eggs every month and cannot regenerate or make new eggs.

The harsh reality is that women are born with a set number of eggs (about 1-2 million). By the time a female goes through puberty, their egg number has already dropped to about 300,000. Every month women continue to lose hundreds of eggs, and this occurs despite being on birth control pills or being pregnant. By the time women are 40 years of age, they only have about 25,000 eggs left, and most of these are of poorer quality.

In fact, under a microscope we can identify discrete differences in the appearance of eggs from women who are in their 20’s versus in their 40’s. Just as our skin cells change with age (think, wrinkles and sunspots), our eggs age with time. This is why its best to try to have children when we are younger rather than older. But easier said than done. Most women delay having children as they pursue their professional career goals, and others are just waiting for Mr. Right. If this is the case, then you should strongly consider egg freezing.

Egg freezing allows women to preserve their eggs, when they are younger and the eggs are of better quality.

The egg freezing process

All too often, women are intimidated to start the process of egg freezing. Maybe they have heard about the hormone shots and have steered clear of the process, or maybe its due to preconceived notions about the cost. Here are some truths about the process:

• An egg freezing cycle typically takes about 2 weeks. On average, most women have to complete 10 nights of shots.
• Most women report only minor symptoms like abdominal bloating or breast tenderness.
• You only need to take one day off of work for the egg retreival (procedure to remove the eggs).
• The egg retreival is completed while you are given twilight sedation so you should feel no pain.
• There are no incisions, and the eggs are removed via a long needle that is placed vaginally.
• The cost can vary from about $5,000-10,000 a cycle.
• Many insurances and employers are now covering egg freezing as a benefit.
• Eggs can be stored for just months or years and used whenever they are needed.
• Egg freezing does not cause you to lose more eggs or have fertility issues in the future.

Why women should freeze their eggs?

The future is not predictable. We have no means in determining which women will have trouble getting pregnant. The only thing we do know, is that with an increase in a female’s age, there are higher incidences of infertility and miscarriages. Additionally, there is a significant drop in in-vitro fertilization (IVF) success rates as women get older. For example, success rates for IVF drop from 50% for women in their early to mid-30’s to just 5% in women who are 42. This demonstrates the importance of freezing eggs the younger you are when the quality of the eggs are better.

How many eggs should be frozen?

The number of eggs a women should freeze varies based on their age. The younger you are, the fewer eggs needed to freeze to ensure a live birth in the future. Older women should freeze more eggs to ensure a future live birth. This often means older women will need to do multiple egg freezing cycles to freeze the appropriate number of eggs.

Typically, we recommend women who are in their early 30’s to freeze about 15 eggs to achieve a future live birth. Women who are in their late 30’s should plan to freeze at least 20-25 eggs to achieve a future live birth. Another way to look at it…there is about a 4-12% chance of pregnancy per egg (oocyte frozen).

Why do you need to freeze so many eggs?

Eggs are very precious and fragile, and not every egg frozen will survive after being thawed. Additionally, after the eggs are thawed their shell is tough. Fertilization of the eggs with sperm requires Intracytoplasmic sperm injection (ICSI), and not all eggs will fertilize normally. Of the eggs that fertilize normally and become an embryo, not all of them will continue grow appropriately in the lab. Even the ones that do grow and divide as expected, may be found to be abnormal in terms of genetics. Abnormal genetics may result in not getting pregnant, or an early miscarriage. Sometimes, we are surprised that very few eggs fertilized normally, or that embryos stop dividing all together in the lab. We don’t have a means of predicting this until the eggs are actually thawed, fertilized with sperm and cultured in the lab.

Because of this, egg freezing and IVF are not a guarantee for a future baby or pregnancy. Instead it allows an option to pause the biological clock. Its important to understand that this is not a set insurance policy and its important to be realistic in your expectations of the process.