OVU Surrogacy & Fertility Network
Posted on 07/27/2022 in Integrative Understanding of Infertility

Egg freezing: not as easy as you thought

Egg freezing: not as easy as you thought

Egg freezing is an attractive and trendy strategy designed for preserving female fertility and delaying pregnancy. And nope, it is not as easy as you thought as it involves stimulation protocols like an Ivf cycle, egg retrieval, vitrification, and storage. Freezing your oocytes while you are 20–Something or 30–Something will give you more freedom to decide when to become a mom. And even if the perfect partner would be a no–show, you will be able to select a Single Motherhood by choice program and do Ivf using own cryopreserved eggs and the Donor’s Sperm. And nope, your oocytes won’t ‘expire’ even if they would be stored for a decade after vitrification. 



What is Oocyte Vitrification?

Oocyte vitrification is a versatile flash–freezing technique designed for cryopreserving the woman’s eggs when she is fertile making it possible to delay motherhood. Vitrification provides a higher thawing survival rate compared to conventional slow freezing (SF). It is a safe technique based on preventing the formation of ice crystals inside the vitrified oocytes by using a high concentration of cryoprotectants and freezing cells at a blazing–fast speed. Plus, this technique has the highest survival rates. The oocyte survival rate after vitrification is up to 90% while after slow–freeze it is 40% maximum.



SlowFreezing vs Vitrification: What to Select? 

The oocyte is the largest cell in the woman’s body measuring approximately 0.14 mm. And most of its inner content consists of water. That is why it needs an effective and sophisticated freezing technique that won’t damage its structure. 


Earlier, egg cryopreservation was performed using the slow freezing technique. It caused egg damage while freezing and thawing. Post–slow freezing survival rates were between 20 and 30%, and almost no oocytes survived. 


Nowadays, most fertility clinics offer the other egg freezing technique, called vitrification. It is characterized by a high concentration of cryoprotectants and a high cooling rate, which prevents the formation of intracellular ice crystals boosting survival rates up to 90%.  



What is the best age to do egg freezing?

There is no minimum nor maximum age for freezing your oocytes. But it is advisable to undergo egg freezing before 35, or in some cases before 37, as the eggs your ovaries produce after this age might be no longer good enough. So, if you are 20–Something or and 30–Something wishing to delay pregnancy, oocyte vitrification is for you. Being young makes it possible to freeze a larger number of good–quality oocytes which can be used in future Ivf or Surrogacy making it possible to avoid egg retrieval. 



10 Why’s to Undergo Egg Freezing

❤If you want to delay pregnancy and would like to be a genetic mom of your baby

❤If you have an irregular cycle and don’t ovulate regularly 

❤If you have a low ovarian reserve

❤If you have a low ovarian response to Stimulation limiting the chances to become pregnant

❤If you have a Double stimulation protocol during the current Ivf and want to cryopreserve extra oocytes so as not to undergo Stimulation again when doing the next Ivf

❤If you cannot continue an Ivf cycle but you are already on the Stimulation stage 

❤If freezing embryos is banned by law in your country but egg freezing is allowed

❤If you undergo therapy that may lead to loss of ovarian function and early menopause

❤If you undergo surgery that may affect your fertility 

❤If you are diagnosed with cancer and must undergo chemotherapy or radiotherapy



Top 10 Benefits Only Egg Freezing Has

❤An oocyte can be cryopreserved for an indefinite period and vitrification won’t cause any abnormalities, so it can be used anytime

❤You will be a genetic mom of your child as each oocyte contains your genetic info 

❤If your country prohibits embryo freezing, egg freezing enables the embryologist to generate new embryos using your vitrified oocytes without starting a new Ivf 

You can do Ivf using own vitrified eggs up to 45–51 years old (depends on ART legislation in your country)

You can request to do shipping of your oocytes to the other countries for doing Ivf there 

No ovarian stimulation in Ivf with own frozen eggs (it gives your endometrium the time to get over the treatment and features higher implantation rates after transfer)

Fewer needles and less medication as you will have only the endometrial preparation cycle, not Stimulation + Preparation cycle like in standard Ivf 

No egg retrieval for Ivf with own frozen oocytes

There is a smart back–up for your Ivf cycle (you may start an Ivf with stimulation to get fresh eggs + own frozen eggs in one cycle)

Tandem oocyte cycle is possible (you can try Ivf with own frozen eggs and fresh/frozen egg donation in one cycle)



Egg freezing process: not as easy as you thought

Oocyte vitrification is very similar to the first stages of any Ivf cycle. It starts with screening and testing, then, a controlled ovarian stimulation is performed to increase the number of eggs that can be produced by the ovaries in a cycle, after Stimulation, the oocytes are retrieved from the ovaries and, once their quality has been verified, they are vitrified until they are used in Ivf or Surrogacy.



Step 1


During the consultation, you will discuss not only your egg freezing options, but also review your family, personal, and gynecological history, and any fertility tests and screenings you have done before. 



Step 2

Health Assessment

You will undergo a screening before freezing your eggs. Usually, it includes:

❤General exam, including blood pressure, height, and weight measurements. 

❤Breast exam.

❤Pelvic exam.

❤Pap smear.

❤Collecting samples for subsequent analysis (cytology) to rule out any infection that may flare up during or after egg retrieval.

❤3D ultrasound scan to confirm that there are no abnormalities or malformations. 



Tests to estimate the Ovarian Reserve:

❤Pelvic ultrasound scan to count the number of antral follicles produced during the first 5 days of the ovarian cycle (Days 3–5 of menses). Average counts of 6 to 12 antral follicles visible on high–resolution ultrasound scanner are considered normal to start the cycle. 

❤Blood Tests for measuring the levels of the hormones to evaluate the Ovarian Reserve & Functioning (AMH, FSH, LH, and E2). 

❤A Genetic Test of Ovarian Reserve can be performed if necessary.

❤Premature Ovarian Failure Panel (Blueprint Genetics) if necessary. 



Other tests: 

❤Blood Group and Rh factor 

❤Complete Blood Count/Hemoglobin (CBC/Hb)

❤Coagulation tests

❤Prolactin (measures the level of the hormone prolactin produced by the pituitary gland. High levels of prolactin can indicate infertility.)

❤TSH (Thyroid–stimulating hormone) Test

❤Screening for sexually transmitted infections (STIs) and other viral & infectious diseases (HIV, Syphilis serology, Hepatitis B (HbsAg), Hepatitis C (HCV), Cytomegalovirus, Herpes Virus, etc.)



Chromosomal & Genetic tests will be performed if necessary: 

❤Chromosome Analysis (Karyotyping) 

❤Fragile X Syndrome Testing 

❤Testing for Thalassemia

❤Carrier Screening for Spinal Muscular Atrophy (SMA)

❤Comprehensive Chromosome Screening (CCS) for detecting more than 600 autosomal recessive diseases

❤Genetic Compatibility Test (GCT) for screening of more than 2300 genes linked to more than 3000 hereditary diseases



Step 3

Post–screening Consultation

When screening and testing are completed and you have the results, you will have a follow–up consultation to discuss all options you have and to get your Stimulation protocol ready. 



Step 4 

Ovarian Stimulation: Single or DuoStimulation protocol 

Stimulation involves using medication and injecting hormones (gonadotropins FSH and HMG) to stimulate your ovaries producing more oocytes. It lasts 8–12 days, depending on each case. Plus, you will take medication that prevents spontaneous ovulation. 


If you have a Duo–Stimulation protocol, then you will have 2 stimulations and 2 oocyte collections performed during a single menstrual cycle (approximately 24–28 days). The first stimulation is done in the follicular phase + egg retrieval and the second stimulation is done in the luteal phase + egg retrieval. Duo–Stimulation makes it possible to retrieve more oocytes compared to the classic stimulation protocol. 



Step 5

Monitoring and Testing

The response of your ovaries to medication and hormones will be monitored via ultrasound scans and blood tests done during follow–up consultations. 



Step 6

Trigger Shot

Trigger Shot (hCG) will be done to induce ovulation as soon as the ultrasound scan confirms that you have several follicles sized 18 to 20 millimeters. In 24–36 hours after the trigger shot, you will have an egg retrieval. 



Step 7

Egg Retrieval

Egg retrieval is done under ultrasound guidance. A long needle is used to aspirate the eggs from the ovaries together with the follicular liquid. It is painless as it is done under anesthesia. And it takes 15 minutes to complete. 



Step 8

Egg Vitrification & Storage 

Once the quality of each retrieved egg has been verified, they are vitrified until they are used in Ivf or Surrogacy. 



Step 9

Using vitrified oocytes in Ivf

When the time for Ivf comes, you can use your vitrified eggs avoiding Stimulation and Follicular Aspiration stages. The oocytes will be thawed and used for creating embryos in the Ivf lab. And you will have an embryo transfer as in classic Ivf. 


Step 10

Storing vitrified oocytes for future cycles

If many oocytes have been vitrified for future Ivf cycle(s), it is possible to devitrify not all of them for doing Ivf but only the necessary number. The rest of the oocytes can be stored in the cryovials for a new cycle as undergoing one more time devitrification and vitrification are stressful for the cells. Alternatively, it is possible to generate the embryos and vitrify them for the future FET cycle.


Egg vitrification is a cutting–edge technique run on sophisticated algorithms of Ivf protocols. It helps to delay pregnancy and preserve fertility for a long time as it doesn’t affect cryopreserved cells. It is a revolution in fertility preservation as it extends the timeframe for doing Ivf and starting your own family.

Get a Free Quote

if you are not sure, we will suggest best price/quality clinics near your location