30 May Overview of Egg Freezing from the US Fertility Network
Egg Freezing Programs
Having a baby is a personal decision, and this requires much thought and consideration. During the decision-making process, many women choose to delay starting a family. For many couples, the right time is not until later in life. Our egg freezing program allow women to store eggs for later use.
Why Choose to Freeze your Eggs?
A woman’s age is the main factor that affects fertility. For women ages 30 to 35, the ability to become pregnant gradually declines, and after age 40, the decline in conception is sharp. Aging increases the risk of complications with conception. For this reason, many women choose to preserve future fertility through cryopreservation (egg freezing). Many women and couples choose to freeze eggs for the following reasons:
- Timing – People have many reasons for not being ready to start a family in their 20s. This is usually due to school, career, travel, and not having met the right partner yet.
- Future family planning – Older women have problems with the ovarian reserve (egg supply). Because of this, freezing the eggs preserves fertility for the future.
- Uncertainty – You may not want children right now, but things change. Freezing the eggs provides you with the opportunity for a family if you decide that is what you desire.
- Known medical conditions – Certain diseases and disorders can impair your ability to have children, such as cancer, premature ovarian failure, and endometriosis.
Vitrification is new technology for egg freezing. This technique allows something with a crystalline structure to be transformed into something smooth, as creating glass using sand. When we freeze egg cells in the laboratory, the main focus is to avoid ice crystal formation as the fluid inside the cells cools to a subzero temperature. Ice crystals are razor sharp and shred the cell membrane. In addition, when water turns to ice, it will expand and destroy the cell. Eliminating the formation of ice crystals preserves the eggs, which is a science called cryobiology.
The vitrification process depends on a high concentration of cryoprotectants, which are used for the slow freezing technique. First, the eggs are exposed to the cryoprotectants, which allow rapid cell dehydration. Next, the eggs are placed in tiny storage devices (straws) to facilitate the ultra-rapid cooling process. Finally, the straws with eggs are cooled quickly, at a rate of thousands of degrees per minute. A typical vitrification protocol is complete within 10 minutes.
Factors Determining Success
Three factors are most important for determining success with egg freezing. These include your serum follicle-stimulating hormone (FSH) level, called the fertility thermostat value, a baseline “resting follicle” count, and your ovarian reserve. These laboratory and diagnostic studies are performed to determine if egg freezing will work for you. An ultrasound is done to assess ovarian reserve and follicle count, and a blood test is used to check FSH value.
The percentages of in vitro fertilization cycle success is slightly lower when frozen eggs are used instead of fresh eggs. According to the American Society of Reproductive Medicine (ASRM), use of frozen eggs yields a 30% pregnancy and live birth rate compared to 50% with fresh specimens. In 2012, ASRM lifted the experimental label from egg freezing technology because of the live birth success rates. A large 2014 systemic review found that vitrification improved clinical pregnancy rate significantly.