As women get older, their fertility declines and their chances of getting pregnant naturally go down. Many women are now considering freezing their eggs in their 30s or early 40s in hopes of preserving their fertility and having a better chance of getting pregnant later on. But is 42 too old to freeze eggs? Let’s take a closer look.
Overview of egg freezing
Egg freezing, also known as oocyte cryopreservation, involves extracting a woman’s eggs, freezing them, and storing them for later use. The frozen eggs can then be thawed, fertilized, and transferred back into the woman’s uterus as embryos to attempt pregnancy. Here is a quick overview of the egg freezing process:
- The woman receives fertility drugs to stimulate her ovaries to produce multiple mature eggs in one cycle.
- Eggs are retrieved in a minor surgical procedure while the woman is sedated.
- Eggs are frozen through an ultra-rapid freezing process called vitrification.
- The frozen eggs are stored long-term in liquid nitrogen at -196°C.
- When the woman wants to try getting pregnant, the eggs are thawed, fertilized with sperm, and transferred as embryos.
What are the age limits for egg freezing?
Most fertility clinics set age limits for egg freezing, as a woman’s egg quantity and quality decline significantly in her late 30s and 40s. Here are the typical age recommendations:
- Ideal age: Under 35
- Maximum age: 40-42 years old
- Over 42: Not routinely recommended
Age 35 is considered the optimal cutoff for freezing your eggs. Success rates start to decline after 35 and drop sharply after 40. Many clinics will not freeze eggs for women over 42 because the chances of retrieving viable eggs are very low.
Success rates of egg freezing at 42
Egg freezing success is dependent on the woman’s age at the time of egg retrieval. The younger the age, the higher the live birth rates. Here is a table summarizing approximate IVF success rates with frozen eggs by age:
|Age at Egg Retrieval||Live Birth Rate with Frozen Eggs|
|Over 42||Less than 5%|
As shown in the table, by age 42 success rates with frozen eggs are quite low, less than 10% per transfer. This is due to the marked decline in egg quantity and quality at this age. Very few viable eggs can be retrieved, and chromosomal abnormalities are common in the remaining eggs.
Egg quantity at 42
A 42 year old woman can expect to produce few eggs in an IVF cycle – often only 2-4 eggs per cycle. This is compared to 10-15 eggs on average for women under 35. With so few eggs, the chances of obtaining 1-2 chromosomally normal embryos after fertilization and genetic testing are very low.
Egg quality at 42
Egg quality also worsens with age, which negatively impacts IVF success rates. By age 42:
- Over 50% of eggs may be chromosomally abnormal and unable to sustain a pregnancy.
- There is an increased risk of miscarriage with genetically abnormal embryos.
- Implantation rates are lower even when transferring chromosomally normal embryos.
All these age-related egg factors lead to very low live birth rates from eggs frozen after age 42.
Other considerations at 42
In addition to low success rates with frozen eggs, there are other risks to consider with egg freezing at advanced maternal age:
Failed egg retrieval
There is a chance that no eggs can be retrieved after going through ovarian stimulation and egg retrieval. The older the woman, the higher this risk. With few eggs to start with, a failed retrieval can waste an IVF cycle.
No viable embryos for transfer
Even if 1-2 eggs are retrieved, after fertilization and genetic testing, there may be no chromosomally normal embryos available for transfer. Again this risk rises sharply after age 40.
Higher pregnancy risks
Pregnancy over age 40, especially with IVF, carries increased risks like gestational diabetes, high blood pressure, preeclampsia, miscarriage, preterm birth, stillbirth, and cesarean delivery. These should be considered before attempting pregnancy.
The biological clock is a major factor. A woman 42 now still has a narrow window of a few years at most to use her frozen eggs. And given limited egg quantity/quality and low live birth rates per transfer, she may need multiple IVF attempts to be successful.
Who might still consider egg freezing at 42?
While success rates are low, egg freezing at 42 may be an option in some situations like:
- A woman who is delaying pregnancy for cancer treatment and wants to preserve future fertility
- A woman with an early menopause diagnosis who needs to freeze eggs immediately
- A single woman who wants to freeze eggs while looking for a partner
However, women in this age group should have a realistic understanding of low success rates and high pregnancy risks later on. Other options like using donor eggs may be discussed.
Alternatives to freezing your own eggs at 42
For women who still hope to get pregnant in their 40s, alternatives to freezing their own eggs include:
Using donor eggs
Donor eggs from a young woman under 30 provide much higher success rates, 50% or more per transfer. The pregnancy is then carried by the 42 year old recipient. Though the child will not be genetically related to the mother, this option provides the experience of pregnancy.
Embryo adoption involves transferring and parenting previously frozen embryos donated from another couple through IVF. Success rates are high with embryos frozen at a young age.
Adopting a child provides the chance to become a mother. Though not biologically related, adopted children are emotionally bonded to the parents who raise them.
Having a child without a partner
Options include using donor sperm as a single woman or co-parenting with a male friend without being romantically involved.
In summary, egg freezing is generally not recommended after age 42 due to low success rates. The quantity and quality of eggs decline substantially in a woman’s early 40s, leading to very low odds of conceiving with frozen eggs after age 42. While pregnancy is still possible, a woman freezing her eggs at 42 needs to be aware of the limitations and risks involved. For women still intent on getting pregnant in their 40s, alternatives like donor eggs, embryo adoption or simply having a child without a partner may be preferable over using one’s own frozen eggs at very advanced maternal age. Each woman’s situation is unique, and a fertility specialist can help tailor the best options given her age, goals and values.