In developing countries, every one in four couples has fertility concerns. The World Health Organization stated these figures in 2004, which have remained consistent as reported in 2012. That is why there is an increasing prevalence of men and women taking measures to preserve their fertility. Egg (and sperm for men) freezing remains one of these processes.
It is an appropriate option for women in their younger years to pursue and prioritise other trajectories instead of entering motherhood within a specific timeframe. Conception and pregnancy can be a tough process for many couples. Egg freezing and in-vitro fertilization (IVF) remain a reasonable and practical option if a woman wants to conceive and start a family at a different time in her life.
Women undergo hormonal imbalances of all kinds (thanks to the stressful, fast-paced, ever-competitive lifestyles). Such imbalances negatively affect her health, including the reproductive system. If she has had her eggs preserved through the freezing process, she can opt for IVF at a suitable time of her choice.
What Is Egg Freezing?
The egg supply of a woman takes a downhill plunge after the age of thirty-five. Both the quality as well as the quantity of eggs decline. Egg freezing is a way to pause the ticking of the biological clock for a woman.
Eggs taken from a woman’s ovaries are frozen unfertilized and stored in designated storage facility centers. The process is called human oocyte cryopreservation. Such storage facilities ensure the appropriate security and safety of the frozen eggs.
It is observed that freezing the eggs does not affect their viability. The eggs are thawed, fertilized, and transferred to the uterus when a woman is ready for pregnancy.
The success rate of egg freezing, conception, and live birth depends on the woman’s age when the eggs were taken. The rates range from 14.8% in the case of a woman aged forty and 31.5% in a woman aged twenty-five.
Why The Need For Egg Freezing?
Egg freezing has been in practice since 1990. The option was available for women at high risk of sterility either because of the disease (such as cancer) or its treatment (chemotherapy).
However, the American Society for Reproductive Medicine (ASRM) released a statement in conjunction with the Society for Assisted Reproductive Technology (SART) in late 2012. The report cautioned against the use of egg freezing (also called oocyte cryopreservation). They attributed their statement to “limited data available about the safety, efficacy, cost-effectiveness and emotional risks involved with egg freezing for healthy women of reproductive age.”
Despite that announcement, there is a rise in the use of social egg freezing in the U.S. Social egg freezing is used for egg freezing for non-medical use. The increase in the prevalence of egg freezing is due to factors like:
- Personal
- Professional
- Financial
- Psychological
The public demand for egg freezing is evident by the announcement made by Facebook and Apple. The two companies declared limited insurance as part of employee benefits to their female personnel if they wanted to freeze their eggs.
The indication for egg freezing is only one; to increase pregnancy chances when the woman is ready for it. The indication umbrellas women under the following categories:
- Those diagnosed with cancer in reproductive years and want to preserve their fertility before beginning chemotherapy or radiotherapy
- Those already undergoing fertility treatment who do not consider embryo freezing options for ethical reasons
- Those who would like to postpone starting a family due to personal or medical reasons yet want to preserve their fertility
- Those suffering from any disease that affects their fertility as an autoimmune disorder or are transgender
What Is The Best Time For Egg Freezing?
A woman carries all her eggs when she is born. The number of eggs declines with age, and so does their quality. This is shown by the fact that the chances of conception and successful pregnancy fall with aging years.
The risk of aneuploidy, a common cause of miscarriage and genetic disorders in newborns, increases in a woman’s egg after the age of forty-five.
So the answer to the question is; the earlier eggs are frozen in the reproductive years, the better are the chances of successful conception and healthy outcome.
The Process Of Egg Freezing
The human egg is the largest of all cells in the body, containing high amounts of water.
Since the freezing process changes one phase (liquid) of egg to another (freeze solid), the ice crystals formed can damage the cell.
To preserve the integrity of the cell, the egg is dehydrated before freezing. For this purpose, cryoprotectants are used. These are substances that save human tissue from freezing damage. The cryoprotectants are filled in the egg cell, thereby replacing the water and inhibiting ice crystal formation.
Two methods are employed to freeze an egg:
- Controlled, slow-cooling method
- Flash-freezing or vitrification process
The latter is a recent modification of the egg freezing process. It utilizes high amounts of cryoprotectants and physically transforms the egg into a solid glass-like cell without crystal formation.
Eggs frozen by the vitrification are associated with higher survival and better development rates than those frozen by the traditional slow cooling method. This is because there is no ice formation inside or outside the egg cell during the cooling, storage and thawing stages.
Vitrification improves the conception rate while attempting IVF. During freezing, the eggshell is modified to prevent fertilization. Fertilization is attempted by direct injection of selected sperm into the egg. The process known as intracytoplasmic sperm injection is part of the IVF routine.
Prerequisites Of Egg Freezing
There are some tests one needs to take before embarking on egg freezing. They provide a baseline measure of a woman’s fertility reserve or egg quantity. These include:
- Blood levels of follicle-stimulating hormone and estradiol on day three of the menstrual cycle to predict the reaction of ovaries to fertility medication
- Blood levels of Anti-Mullerian Hormone (AMH)
- Tests for screening infectious disease like HIV, hepatitis B and C
- Ultrasound of the ovaries and uterus showing antral follicle count (counting the number of egg follicles appearing on both ovaries)
The fertility tests help the fertility specialist to design a treatment plan that maximizes the results of IVF.
These tests also help tailor medications used for ovarian stimulation to make the most egg output during treatment.
Further, such testing allows for determining the optimum fertility window for a woman to decide on the deadline for starting a family according to her health status.
How Many Eggs To Freeze?
The answer varies. The fertility profile of a woman usually dictates the response. Other prescribing factors include:
- The number of children a woman wants
- Age of a woman at the time of egg freezing
- The number of eggs retrieved from one cycle
As the chances of healthy conception and pregnancy decline with age, more eggs will be required. If the fertility profile does not look good, it may need more than one cycle to retrieve enough eggs.
However, if the fertility profile is good enough, enough eggs are retrievable in one cycle. About 75% of them go through successful thawing and IVF procedures.
The Process Of Egg Freezing – What To Expect?
The process of egg freezing follows the same steps as IVF. The only difference is that instead of being fertilized with sperm, the eggs are sent for freezing and storage.
- Ovarian suppression
After the baseline fertility testing, the next step in the egg freezing process is ovarian suppression. Birth control pills are prescribed for two to four weeks. Also, daily self-injections of Lupron are given for about two weeks.
- Some more tests
Tests including ultrasound and blood tests are carried out to ensure that ovarian suppression is achieved.
- Ovarian stimulation
Next comes ovarian stimulation via taking synthetic hormones to stimulate the ovaries to produce multiple eggs instead of a single egg typically produced per cycle.
This involves continuing lower-dose lupron injections (that suppresses premature ovulation) with nightly injections of ovarian stimulation medication for 10 to 14 days. These include medication as follitropin alfa or beta or menotropins.
- Cycle monitoring
Usually, on the fifth day of receiving injections for ovarian stimulation, follow-up, every alternate day, to check the body’s response to medications is done. Blood tests check the estrogen and progesterone levels. Ultrasound of ovaries shows the development of follicles containing mature eggs.
- A trigger shot
After ten to fourteen days of the cycle, the eggs mature and are ready for retrieval from the follicles. At this time, an injection of human chorionic gonadotropin (Pregnyl, Ovidrel) is given.
- Egg retrieval and storage
After exactly about 36-hours of the human chorionic gonadotropin injection, retrieval of eggs can begin.
This is usually done under sedation (via intravenous anesthesia) in a clinical setting.
The doctor inserts an ultrasound probe through the vagina and identifies the follicles. An aspiration needle is guided through the ultrasound probe, and a suction device removes the eggs from the follicles. Multiple eggs can be removed in one session.
- What to look out for?
After retrieval, the eggs are sent for freezing, followed by storage. Slight cramps in the lower abdominal area may be present. The woman who has undergone this procedure can resume normal activities within a week. Adopt safe sex practice to prevent unintended pregnancy.
Side Effects Of Egg Freezing Process
The main side effects of this process are related to ovarian stimulation medications and egg collection.
Some precautions to be taken in this period include looking out for:
- Fever
- Severe abdominal pain
- Heavy vaginal bleeding
- Problems in urinating
- Unexplained weight gain of more than 2 pounds in 24 hours
The medications may result in a condition called ovarian hyperstimulation syndrome (OHSS). It is a temporary condition when the blood vessels leak fluid from blood vessels into the surroundings due to the increased permeability of the vessel walls. The situation is usually mild most of the times, presenting as:
- Abdominal bloating and distention
- Discomfort
- Nausea
The symptoms may progress to cause pain due to increased abdominal bloating and vomiting. Since there is fluid leakage in the abdominal cavity, the kidneys try to maintain the fluid levels by restricting urine output.
A severe case of OHSS requires hospital care and presents as;
- Severely distended abdomen
- Thirst
- Dehydration
- Shortness of breath
- Minimal or nil urine output
The treatment of OHSS is symptomatic. The condition usually resolves within 7-10 days. Reducing the dose of gonadotropins (FSH) and using a GnRH agonist trigger (instead of an hCG trigger) helps avoid the situation. This should be discussed with the doctor beforehand.
Side effects related to egg collection include
- Bleeding
- Infection
The ovaries are highly vascularized because of drug stimulation. A small amount of bleeding is expected as the needle passes through the ovarian tissue. In case of severe bleeding, surgery may have to be done.
Fever usually indicates local infection. It may happen if proper sterilization techniques have not been adopted. It is a rare occurrence in reputed clinics.
Cost Of Egg Freezing
The total cost of egg freezing depends on the physical health and age of the woman.
On average, it costs around $30,000 to $40,000. It includes the cost per cycle, which is approximately $15,000 to $20,000 per cycle, covering the cost of medical treatment, the cost of medication, and the cost to store the frozen eggs.
The cost varies from clinic to clinic and from state to state and by country. Some clinics have add-ons like consultation fees, while others cater to IVF as a separate procedure.
What Is In-Vitro Fertilization (IVF)?
Fertilization that takes place outside a woman’s body is called in-vitro fertilization. This is an advanced fertility treatment, a type of assisted reproductive technology (ART) that takes place in the laboratory.
It involves retrieving eggs from a woman’s ovaries and fertilizing them with sperm under specific lab conditions. This fertilized egg, known as an embryo, can either be frozen for storage or transferred to a woman’s uterus.
IVF may be done as fertility treatment or a sequential part of the egg freezing process.
The indications for IVF include:
- Women more than 35 years of age with fewer eggs or eggs with a high risk for chromosomal abnormalities
- Women with blockage of fallopian tubes (the passageway between ovaries and uterus)
- Women who have endometriosis, uterine fibroids, or polycystic ovarian syndrome, conditions that decrease their chances of conception
- Men with decreased sperm count or having subpar quality sperms (that are unable to reach and fertilize an egg naturally)
- Women with a history of recurrent miscarriages
- After failed attempts at fertility treatments
- Unexplained infertility
The same baseline tests are followed for IVF as those for egg freeze. Ultrasound of the uterus is also done. The tests are done for the couple.
The same steps are followed for IVF as those observed for egg freezing. The difference is:
- Sperm is taken from the male partner or a sperm donor
- Instead of sending the eggs for freezing, a healthy egg is selected and immediately sent for in-vitro fertilization
- The embryo is cultured and observed to see if it is dividing. Any tests to exclude genetic abnormalities or disease are done at this time
- Transfer of the embryo is done three to five days after fertilization
- Successful pregnancy occurs when the embryo implants itself in the uterine wall in about six to ten days.
- Blood tests and ultrasound confirm pregnancy
IVF is an expensive fertility solution requiring a couple to make many personal decisions. It has its side effects as multiple pregnancies, ectopic implantation of the embryo, infection, OHSS, and miscarriage. However, the live birth rate for women aged below 35 with IVF is 41% to 43%, which is good news for many wanting to have a healthy baby.
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