WHAT IS EGG FREEZING AND HOW DOES IT WORK?
Egg freezing - medically termed human oocyte cryopreservation - is the process of extracting and storing a woman's unfertilised eggs. This treatment enables women to extend their future opportunities to conceive; think of it as becoming your own future, younger egg donor.
Egg freezing involves vitrification of human oocytes, ideally when you are young, fertile and eggs are more numerous. These can be used via IVF to create babies, even at a later stage of life.
Vitrification is an advanced freezing method used to preserve oocytes effectively and from a scientific perspective indefinitely, with more than 85 per cent of [1]frozen eggs expected to survive the warming process without any cryodamage.
Revolutionary advancements in technology have resulted in our ability to successfully cryopreserve human eggs, making egg freezing an exciting and increasingly popular treatment opportunity for women and all people with ovaries.
YOUR GUIDE TO EGG FREEZING
Jump to:
→ What is egg freezing and how does it work?
→ The egg freezing journey (what to expect)
→ The egg freezing process (step by step)
→ How to prepare for the egg freezing treatment
→ Egg freezing success rates and outcomes
→ Egg freezing costs and financing options
→ Is egg freezing right for you
→ The emotional aspects of egg freezing
BENEFITS OF EGG FREEZING
Egg freezing represents a paradigm shift in reproductive medicine from “reactive” IVF (commonly in response to age related infertility) to a new model of pro-active fertility care.
In an age of innovation and disruption, our target, through egg freezing is to reduce the impact of a ticking biological clock.
While having oocytes on ice cannot guarantee a future live birth in absolute terms, more women who have frozen their eggs are predicted to be able to become mothers to the number of children they aspire to when the time is right.
THE EGG FREEZING JOURNEY: WHAT TO EXPECT
Initial consultation: your first step
If you're interested in exploring your options for egg freezing, the first step is to make a fact-finding appointment at Women's Health Melbourne. Our team will take this opportunity to learn more about you, get a thorough understanding of your medical history and discuss your goals. From this initial appointment, our team will arrange all the important preliminary tests required to educate you about your current fertility status and future planning choices.
Before the treatment, whats involved:
Once you have made the decision to freeze your eggs, you will be requested to register as a patient of your WHM CREI trained fertility specialist (Dr Raelia Lew, Dr Sylvia Ross or Dr Rebecca Mackenzie Proctor). You will then have several multidisciplinary appointments preparing you for your treatment cycle:
1. A planning appointment with your WHM CREI trained Fertility Specialist (Dr Raelia Lew, Dr Sylvia Ross or Dr Rebecca Mackenzie Proctor) to ensure that you have a thorough understanding of your personalised egg freezing strategy. You will decide with your specialist whether to proceed during your natural cycle (beginning when you have a period) or with a start date scheduled to suit your convenience, timed around any important commitments you may have. This is known as a planned start, random start or chosen start egg freeze cycle and your medication plan will be adapted accordingly (depending on the timing of your egg freeze treatment start relative to your phase of natural menstrual cycle).
2. An appointment with an ANZICA qualified fertility counsellor. This is a wonderful and engaging experience that presents an opportunity to explore your current and future fertility plans, as well as learning important information about the Victorian Assisted Reproductive Treatment Act and how to keep your eggs in storage for as long as you may require.
3. An appointment with a specialist fertility nurse from our amazing team. Your nurse will go through (in minute detail) exactly what you will need to do during your treatment. They will develop a timeline with specific written instructions for you on when and what you need to do (e.g. administering medications, attending an ultrasound scan or blood test appointment).
We also recommend Cycle Guide, a personalised, scheduling app to help you keep track of your cycle.
THE EGG FREEZING PROCESS (STEP BY STEP)
-
An egg freezing cycle is often described as similar to an IVF cycle. However, there are several important differences.
The end point of an egg freezing cycle is the vitrification of mature eggs. This is different from IVF where the goal of treatment ultimately leads to an embryo transfer, with the aim of conceiving a pregnancy.
Several treatment choices used in IVF, which are designed to achieve development of the embryo and endometrium (uterine lining) in synchrony, are not relevant to egg freezers.
Three medications are necessary during an egg freezing cycle:
Follicle stimulating hormone (of which several options exist) – to help follicles and eggs grow
A class of medications that prevent ovulation before eggs have been collected. Options include a GnRH antagonist or a form of the hormone progesterone.
A trigger medication, allowing for final egg maturation so that egg collection can proceed. GnRH agonists – a class of medication used to promote an endogenous pituitary LH surge, is preferred for most patients. An alternative trigger medication commonly used in IVF is b-HCG, the pregnancy hormone which as a molecule is physically similar to LH.
For most egg freezers, a GnRH antagonist cycle is the safest treatment choice. Complications of ovarian hyperstimulation syndrome (OHSS), which can sometimes occur in IVF cycles are virtually eliminated using our advanced egg freezing treatment strategy. However, there are many intricacies in fertility management and ovarian stimulation is as much an art as a science. In your individual circumstances, an alternative tailored approach may safely achieve better results for you.
Furthermore, because the thickness and “synchrony” of the endometrium is not a consideration in egg freezing, stimulating follicles for longer than usual in standard IVF can achieve more eggs collected per cycle of egg freezing.
Our specialist team will perform monitoring ultrasound assessments of your cycle progress and keep you fully informed. We are passionate about achieving the very best outcomes for our patients, both in terms of egg numbers achieved per cycle and the ease of our patients’ treatment experience.
-
The procedure for egg collection in an egg freezing cycle is identical to how eggs are collected for IVF. When your follicles have grown to approximately 2-3cm in diameter, the time has come to collect your eggs.
Egg collection is achieved through a technically precise transvaginal ultrasound procedure known as an OPU (Ovum Pick Up), sometimes called EPU (Egg Pick Up).
While you are asleep, under real time ultrasound vision, we will gently collect your eggs. Using a fine needle introduced trans-vaginally (through the vagina, into the ovary), fluid from the follicles is aspirated. Our scientist then searches under a high-power microscope to locate your eggs.
It is important to note that not every follicle contains an eggs. Eggs are microscopic and can neither be confirmed with the naked eye, nor via ultrasound. It is usual that more follicles may be noted on a pretreatment ultrasound than eggs ultimately found and designated suitable for vitrification.
For an egg to be frozen, it must be of suitable quality to be utilised for future IVF.
In ART (assisted reproductive treatment) timing is important. From many years of practice, we know that having a gentle, skilled and reassuring doctor perform critical IVF procedures with excellence is an imperative part of egg freezing and IVF success.
We want to make sure our patients are provided this care with certainty. We also want to ensure optimal timing of every assisted reproductive treatment procedure. Working collaboratively allows us to ensure your egg collection will optimally timed. Around your cycle, not your individual fertility specialists schedule. You can know for sure and be confident, whatever day of the week or time of the day your treatment needs to occur, you will be cared for by an elite IVF specialist with great expertise when it comes to egg collection.
Your WHM specialist will always put you first. When timing your egg freezing procedure – your successful outcome will always be our top priority.
-
Once in the IVF lab, your eggs are assessed for maturity, and immature eggs are given time to catch up. A proportion of eggs will be deemed immature (germinal vesicles (GV) or metaphase I (MI) oocytes) or may be degenerating (losing their cellular integrity) and these will be unsuitable to freeze (this is usually about 10% of the total number of eggs collected however in individual cases the proportion of oocytes unsuitable for vitrification may vary).
-
Vitrification is a revolutionary method for freezing eggs, resulting in over 85% of eggs[2] surviving the freeze/warming process. Vitrification reduces the risk of ice crystals forming within eggs while they are in the process of freezing and warming. This is achieved by gently dehydrating the egg, then drawing out the water content by bathing the egg in a series of cryoprotectant solutions. Eggs are then frozen instantly by plunging them into liquid nitrogen at temperatures of less than -200 degrees celcius. Once vitrified and safely stored, eggs can remain frozen indefinitely until you may need to use them to have a baby.
We use the Rapid-I vitrification system to freeze your eggs.
-
The process of egg freezing takes between 10 days to two weeks. During the first part of your cycle, you will be able to continue your normal routine. With the exception of needing to attend your treatment monitoring appointments, you won't be impaired in your daily activities.
You will need to take two days off for the day of your egg collection and probably the day after in order to take it easy. The following day, you will feel very well. We advise you should avoid sexual activity during your egg freezing cycle and in the week immediately after.
This is to avoid unwanted pregnancy and the risk of trauma to your ovaries which will be enlarged due to treatment. It is also advisable that you avoid contact sports during this time. You will get your period within 1-2 weeks after your cycle is completed. It is normal for the timing of this period to vary from your regular cycle.
If you are planning more than one treatment cycle, a break in between of at least one month is usually advised.
GET STARTED
If you are contemplating egg freezing and would like to know more about your options, contact Women's Health Melbourne to arrange a Well Woman Fertility Health Check assessment.
HOW TO PREPARE FOR EGG FREEZING TREATMENT
Optimising Egg Quality for Treatment
Prior to egg freezing treatment, we recommend taking the below steps to maximise the quality of your eggs ahead of the treatment process:
1. Take folic acid 500mcg daily for one month prior
2. Take vitamin D 1000mg daily for one month prior
3. Take melatonin 4mg before bed for one month prior
4. Quit smoking (ideally three months prior)
5. Quit alcohol (during the treatment cycle)
6. Avoid excessive caffeine (one espresso daily is permissible)
7. Some women with a lower egg reserve may benefit from androgen priming therapy pre-treatment
8. High dose antioxidants can also be prescribed to help enhance egg quality.
In your fact-finding initial appointment, personalised pre-treatment ovarian priming supplements will be recommended and prescribed for you to use in preparation for egg freezing.
Acupuncture is a fantastic treatment option to add to your egg freezing cycle as it is believed to encourage blood flow to your ovaries. Blood carries antioxidants and nutrients to your ovaries, therefore, optimising the environment in which the follicles are growing. Acupuncture also helps manage the negative effects stress plays on the hypothalamic-pituitary-adrenal axis which ultimately controls ovulation and ovarian stimulation. Acupuncture can also help minimise any side effects that a woman may experience from her ovaries being stimulated. Acupuncture after egg pick up is helpful with recovery and post-surgical discomfort.
You may arrange a specialist acupuncture consultation in the lead up to egg freezing treatment at WHM with Mandi Azoulay as part of our holistic approach to egg freezing treatment.
MEET OUR EGG FREEZING SPECIALISTS
-
DR RAELIA LEW
CREI Fertility Specialist
Director of Women’s Health Melbourne -
DR SYLVIA ROSS
CREI Trained Fertility Specialist
-
DR REBECCA MACKENZIE-PROCTOR
CREI Trained Fertility Specialist and Gynaecologist
EGG FREEZING SUCCESS RATES AND OUTCOMES
-
Happily egg freezing success rates are now similar to same age IVF success rates for women aged under 35 years.[3]
We expect that 80-90% of frozen eggs will survive warming
1 in 2 eggs will fertilise normally
2 in 3 fertilised eggs will develop into a cleavage stage embryo
1 in 5 eggs warmed will develop into a blastocyst embryo
1 in 3 blastocysts will result in a live birth
-
International studies demonstrate an overall 6 to 12 per cent chance of full-term birth per egg warmed. This means that the majority of women who freeze 20 eggs when they are young and healthy would be able to successfully use those eggs to have a baby through IVF in the future.[4]
-
While there are no guarantees in life, younger women who freeze more eggs can always expect better outcomes. Women who can't immediately try for a baby are recommended to freeze a good number of eggs (ideally 20 to 30) at an age where eggs are likely to be of high quality. This allows for greater reproductive freedom, with a high chance of future pregnancy.[5]
We recommend freezing 20-30 eggs which for an average woman under 35 would require two egg collections.
For personalised prognostic advice, make an appointment with a WHM CREI fertility specialist.
-
EGG FREEZING COSTS AND FINANCING OPTIONS
Egg Freezing Costs
Women should budget $5,000 - $6,000 of specialist and laboratory out-of-pocket costs per cycle for elective egg freezing. Many women need to freeze eggs over serial cycles.
Additional costs for hospital day stay, medications and anaesthesia usually apply. Medicare and Private Health Insurance Fund rebates may apply for women seeking to freeze their eggs who have underlying fertility concerns.
-
Medicare Australia does not fund egg freezing when undertaken for elective reasons, as treatment is currently regarded 'non-essential' (in the same category as cosmetic procedures) and is therefore fully-patient funded.
There are few exceptions to this. Medicare rebates only apply to medical fertility preservation – for example if your ovarian reserve is dangerously low, if you have a serious fertility-threatening condition or if you are about to start chemotherapy for life-saving cancer treatment
At Women’s Health Melbourne, we endeavour to make the highest-quality care as affordable as possible.
-
This space may change in the future but currently most Australian Health Insurers will only contribute to funding the costs of egg freezing for medical reasons. Ask your health insurer if they are able to contribute to your egg freezing hospital day surgery costs under your elected private health insurance policy.
-
WHM provides a boutique Melbourne based specialist service for egg freezing in a non-corporate model. Our high quality care is cost-effective and value driven. As a smaller scale personalised care focused boutique unit, we are unable to provide financing or payment plans to assist patients at this time.
-
FREEZING 30 EGGS AT AGE 30
Provides a greater than 90% probability of being able to have two babies.
IS EGG FREEZING RIGHT FOR YOU?
Reasons women consider egg freezing
There are many reasons why you might be considering freezing your eggs, including changing life, health or career circumstances, unexpected events or perhaps you’re simply seeking further knowledge and solutions to offset potential age-related fertility barriers.
At Women’s Health Melbourne, our philosophy is to make access to egg freezing as straightforward, empowering, enjoyable, affordable and high value experience as possible.
No matter what your motivations might be, exploring your options will allow you to make an informed, intelligent plan for the future.
Our respected, highly qualified team will ensure that you feel confident and supported with a personalised strategy that is best-suited to your unique goals.
-
This is a key reason women choose to freeze eggs while they remain younger, healthier and more fertile. Having frozen eggs can in theory assist women to have greater reproductive time, better overall fertility and IVF potential outcomes and more flexibility when planning a family[6].
-
Women may suffer fertility threatening illnesses or risk factors that lead them to consider egg freezing. Examples include endometriosis and other pelvic pathology, premature ovarian insufficiency with known diminished ovarian reserve, threats of cancer and related therapies mandating delayed childbearing and potentially causing gonadotoxic effects, or known genetic reasons for future IVF.
-
Not everyone is ready to have a baby when it is biologically more ideal. From an egg quality perspective, women are most fertile in their teens and early 20’s. This is not a common time for the modern woman to have children. More and more women are seeking pregnancy beyond the age of 35 years when serious fertility decline becomes a real and common problem. Freezing eggs when a woman is younger can be a important part of her long term family building game plan.
Age and Fertility: What You Need to Know
Women are born with equipped with every egg they have for their whole reproductive lifetime. Unlike men who produce sperm constantly from stem cells throughout their adult lives, women rely on eggs formed when they themselves were a fetus.
Eggs wait a long time before they are ovulated and have a chance to make babies. Eggs fatigue as a woman ages, and are more likely to make serious errors when they have the opportunity to try to create a pregnancy later in life[7].
However, freezing eggs can avoid this issue. When eggs are frozen through vitrification, the aging process is arrested. Eggs retain their youthful potential, even when they are warmed and fetilised years or even decades after they were frozen[8].
This means in theory, a 40 year old woman can retain her personal 30 year old self’s IVF success rates, by utilising her own biological eggs she chose to freeze a decade earlier.
EMOTIONAL ASPECTS OF EGG FREEZING
Egg freezing can be an emotional experience on many levels. The most common reason women cite when they decide to freeze their eggs is the lack of a partner currently committed to a long term relationship or ready to have a baby[9].
The modern women is well educated and aware of how age has negative and progressively serious effects on fertility. This can cause significant anxiety and stress for women who know they once day want to become mothers. Egg freezing is a significant investment in wellbeing, future fertility and self care.
However the financial commitment can mean forgoing other needs or opportunities at that time and this can be a source of emotive reflection.
Finally the egg freezing process itself can feel very emotional, confronting fears of self injecting medications (ultimately the majority of women take this in their stride with pride at the accomplishment). Hormone changes during egg freezing are temporary and contextually expected but can nevertheless feel intense. In summary, freezing your eggs can be emotional!
Our fertility and egg freezing specialist at Women’s Health Melbourne
Dr Raelia Lew, Dr Rebecca Mackenzie Proctor and Dr Sylvia Ross are our WHM Fertility dream team. They are each supportive, caring doctors with advanced CREI training and a pioneering female-focussed approach to the field of infertility. A RANZCOG Board Certified Reproductive Endocrinologist & Fertility Specialist (CREI), Dr Raelia Lew leads the WHM team of elite fertility experts, each providing our patients with the highest level of expertise.
Dr Raelia Lew has both the quaeications of FRANZCOG (Fellow of RANZCOG), and higher certification in Reproductive Endocrinology and Infertility medicine and surgery (CREI). Fewer than 2% of specialists currently practising in the field of fertility medicine are RANZCOG Board Certified CREI Subspecialists, making Raelia's level of expertise truly unparalleled.
Raelia is the lead author of the current ANZSREI and RANZCOG ACCEPT guideline on Electiove Oocyte Cryopreservation.
With state-of-the-art technology, beautiful and modern facilities and an industry-leading team supporting our CREI trained fertility specialists, Women’s Health Melbourne ensures that every patient feels safe, comfortable and fully informed throughout every stage of the egg freezing process.
MAKING YOUR DECISION
Questions to ask yourself
-
Freezing your eggs is something you may need to plan for and budget for.
-
Freezing eggs cannot absolutely guarantee that you will be able to have a live birth in the future using your frozen eggs. However greater than 90% of women aged greater than 35 years who freeze less than 20 eggs predicted to be able to have at least one baby[10].
-
You will need to take at least one and ideally two days off work for your egg collection procedure for each cycle of egg freezing that you undertake.
-
This decision is personal and depends on your needs, aspirations and circumstances. Seek holistic advice from a CREI Fertility Specialist at WHM. We will be able to advise and guide you based on your thorough assessments. Supportive counselling is an important part of the decision making process.
-
This depends on your personal circumstances including your age and ovarian reserve when you choose to freeze your eggs. Most women require one or two treatment cycles when eggs are frozen electively under the age of 35 years.
-
Ideally eggs should be vitrified at the youngest age practical once you have made the decision to do it. Try to undertake egg freezing before the age of 35 years for your best possible future IVF outcomes using frozen eggs to conceive.
FAQS ABOUT EGG FREEZING
-
Freezing your eggs creates a future reproductive resource for women approaching or over 30, where immediate pregnancy is not always a viable option. This strategy maximises a woman’s chance of having her own family at a time that she feels ready.
Having chosen to freeze eggs, many women will then go on to utilise those frozen eggs and successfully conceive in the future. However there will come a time to consider the fate of any eggs that remain in storage. Eggs may remain in storage because:
● Natural pregnancies were achieved without using frozen eggs
● Pregnancies were achieved using some frozen eggs, with additional eggs remaining.
In such circumstances, your choices would include:
● Keeping your eggs in storage (with the option of trying for another baby later)
● Warming and discarding your frozen eggs
● Becoming an egg donor (providing a precious gift to a woman or family with infertility)
-
Egg quality may still be reasonable and even good for young women who have a low AMH (indicative of a diminished ovarian reserve). Egg freezing may still be an option and potentially a very worthwhile endeavour for women with a low AMH. Having a low AMH indicates that a lower number of eggs would be predicted to be achieved per cycle of treatment. it is predictable and highly likely that women who have a low AMH may require more cycles of egg freezing to achieve a reasonable number of vitrified oocytes compared to same age women with a more normal ovarian reserve.
Is AMH a test of fertility?
AMH stands for Anti Mullerian Hormone. AMH is not a stand alone test of fertility. It can diagnose a woman with a low, high or normal range ovarian reserved. It cannot diagnose how easy or difficult it may be for her to conceive now or in the future. Age is the most important factor when it comes to egg quality and risk of future infertility. AMH is a test of egg number rather than a test of egg quality. However having a low AMH is a significant disadvantage when it comes to a woman’s chance of pregnancy via egg freezing and IVF as having fewer eggs collected in an IVF or egg freezing cycle is predicted.
-
Biologically there is no limit on how long you can keep your eggs frozen before using them. Studies examining eggs frozen by vitrification show their structure, integrity, gene expression and pregnancy potential does not deteriorate over time, even after having spent years in the freezer. [11]
-
Like all medical procedures, freezing your eggs can be associated with risks. While risks of adverse events associated with oocyte cryopreservation are rare (affecting fewer than 1 in 1000 cycles) these can occur.
Examples include:
Significant surgical complication such as bleeding or pelvic infection after egg collection
Escape ovulation prior to ovum pick up
Empty follicle syndrome/trigger medication failure resulting in no eggs being collected
Some eggs being unsuitable to freeze
Failure to conceive or give birth despite having frozen your eggs
-
We recommend a goal should be to freeze 20-30 eggs for women aged < 35 years. In a single cycle if you produce fewer eggs than your target/goal, your WHM fertility specialist will advise and offer you the opportunity to collect further eggs in a subsequent treatment cycle. Over time, you may undertake serial treatment cycles and reach your goal.
-
In Australia, Medicare and Private Health Insurance subsidies are currently only payable for fertility treatment when your doctor agrees there is a medical indication to freeze your eggs. Cycle costs are dependent on your circumstances as are how many treatment cycles it may take to reach your goal.
Our admin team will be able to advise you accurately following your personalised specialist fertility appraisal as to whether your egg freezing treatment is medical or elective and associated costs and rebates depending on that assessment.
Our costs for both elective egg freezing and medical egg freezing are among the most competitive and best value in Melbourne.
-
Fertility preservation includes egg freezing (oocyte vitrifiaction) embryo freezing and ovarian tissue cryopreservation. All these options may be valid, and each can have specific advantages depending on your circumstances.
When women are given a cancer diagnosis and may have a limited amount of time to act, egg or embryo freezing (which takes 2-3 weeks) may not be a safe option for them. It is in this circumstance that the more experimental technique of ovarian tissue cryopreservation can be offered [12]. Over 130 live births world wide have now been achieved through ovarian tissue cryopreservation and subsequent reimplantation.
Ovarian tissue can be harvested for cryopresevation through laparoscopic surgery and can be done quickly. It may not be suitable for patients with blood borne cancers as there is a risk of cancer recurrence when tissue is reintroduced into the body after remission if the tissue contains blood borne cancer cells. Ovarian tissue can be a fertility preservation option for female children with cancer.
-
When it comes time to become pregnant - you will need to meet with your WHM Fertility Specialist and prepare.
Routine essential health checks will be undertaken and preconception advice provided wo you and your partner if relevant. You can also use frozen eggs to conceive with sperm from a donor if preferred.
A plan will be made for eggs to be warmed at an appropriate stage of your menstrual cycle and fertilised with sperm using a technique known as ICSI (intracytoplasmic sperm injection). Five days later, the plan will be to return your strongest embryo to your womb. Further embryos that have formed can be frozen and used in future cycles if needed. Just 10 days later, we will know if you have become pregnant.
-
Speak to your WHM Fertility Specialist who will create a strategic plan to maximise your cumulative chance of having the family you want using frozen eggs. Often you may be advised to warm only a portion of your eggs in a single cycle. This can maximise your chance of pregnancy via increasing a statistic known as “utilisation”. Occasionally embryos are lost when they are frozen and warmed. “Batching” eggs warmed minimises this risk by reducing the number of embryos that will need to be “refrozen” having been vitrified and thawed as an egg.
References
1. Cobo A, García-Velasco JA, Remohí J, Pellicer A. Oocyte vitrification for fertility preservation for both medical and nonmedical reasons. Fertil Steril. 2021 May;115(5):1091-1101. doi: 10.1016/j.fertnstert.2021.02.006. PMID: 33933172.
Cobo A, García-Velasco JA, Coello A, Domingo J, Pellicer A, Remohí J. Oocyte vitrification as an efficient option for elective fertility preservation. Fertil Steril. 2016 Mar;105(3):755-764.e8. doi: 10.1016/j.fertnstert.2015.11.027. Epub 2015 Dec 10. PMID: 26688429.
2. Lew R, Foo J, Kroon B, Boothroyd C, Chapman M; Australasian CREI Consensus Expert Panel on Trial evidence (ACCEPT) group. ANZSREI consensus statement on elective oocyte cryopreservation. Aust N Z J Obstet Gynaecol. 2019 Oct;59(5):616-626. doi: 10.1111/ajo.13028. Epub 2019 Jul 22. PMID: 31332788.
3. Doyle JO, Richter KS, Lim J, Stillman RJ, Graham JR, Tucker MJ. Successful elective and medically indicated oocyte vitrification and warming for autologous in vitro fertilization, with predicted birth probabilities for fertility preservation according to number of cryopreserved oocytes and age at retrieval. Fertil Steril. 2016 Feb;105(2):459-66.e2. doi: 10.1016/j.fertnstert.2015.10.026. Epub 2015 Nov 18. PMID: 26604065.
4. Walker Z, Lanes A, Ginsburg E. Oocyte cryopreservation review: outcomes of medical oocyte cryopreservation and planned oocyte cryopreservation. Reprod Biol Endocrinol. 2022 Jan 7;20(1):10. doi: 10.1186/s12958-021-00884-0. PMID: 34996479; PMCID: PMC8740039.
Cobo A, Meseguer M, Remohí J, Pellicer A. Use of cryo-banked oocytes in an ovum donation programme: a prospective, randomized, controlled, clinical trial. Hum Reprod. (2010) 25:2239–46. 10.1093/humrep/deq146 [PubMed] [CrossRef] [Google Scholar]
Rienzi L, Romano S, Albricci L, Maggiulli R, Capalbo A, Baroni E, et al.. Embryo development of fresh versus vitrified metaphase II oocytes after ICSI: a prospective randomized sibling-oocyte study. Hum Reprod. (2010) 25:66–73. 10.1093/humrep/dep346 [PMC free article] [PubMed] [CrossRef] [Google Scholar]
Trokoudes KM, Pavlides C, Zhang X. Comparison outcome of fresh and vitrified donor oocytes in an egg-sharing donation program. Fertil Steril. (2011) 95:1996–2000. 10.1016/j.fertnstert.2011.02.035 [PubMed] [CrossRef] [Google Scholar]
Solé M, Santaló J, Boada M, Clua E, Rodríguez I, Martínez F, et al.. How does vitrification affect oocyte viability in oocyte donation cycles? A prospective study to compare outcomes achieved with fresh versus vitrified sibling oocytes. Hum Reprod. (2013) 28:2087–92. 10.1093/humrep/det242 [PubMed] [CrossRef] [Google Scholar]
García JI, Noriega-Portella L, Noriega-Hoces L. Efficacy of oocyte vitrification combined with blastocyst stage transfer in an egg donation program. Hum Reprod. (2011) 26:782–90. 10.1093/humrep/der008 [PubMed] [CrossRef] [Google Scholar]
Cobo A, Garrido N, Pellicer A, Remohí J. Six years' experience in ovum donation using vitrified oocytes: report of cumulative outcomes, impact of storage time, and development of a predictive model for oocyte survival rate. Fertil Steril. (2015) 104:1426-34.e1–8. 10.1016/j.fertnstert.2015.08.020 [PubMed] [CrossRef] [Google Scholar]
5. Poli M, Capalbo A. Oocyte Cryopreservation at a Young Age Provides an Effective Strategy for Expanding Fertile Lifespan. Front Reprod Health. 2021 Sep 22;3:704283. doi: 10.3389/frph.2021.704283. PMID: 36304057; PMCID: PMC9580690.
6. Telfer EE, Grosbois J, Odey YL, Rosario R, Anderson RA. Making a good egg: human oocyte health, aging, and in vitro development. Physiol Rev. 2023 Oct 1;103(4):2623-2677. doi: 10.1152/physrev.00032.2022. Epub 2023 May 12. PMID: 37171807; PMCID: PMC10625843.
7. Han E, Seifer DB. Oocyte Cryopreservation for Medical and Planned Indications: A Practical Guide and Overview. J Clin Med. 2023 May 18;12(10):3542. doi: 10.3390/jcm12103542. PMID: 37240648; PMCID: PMC10218997.
8. Stigliani S, Moretti S, Anserini P, Casciano I, Venturini PL, Scaruffi P. Storage time does not modify the gene expression profile of cryopreserved human metaphase II oocytes. Hum Reprod. 2015 Nov;30(11):2519-26. doi: 10.1093/humrep/dev232. Epub 2015 Sep 18. PMID: 26385790.
9. Chin HMS, Rajesh H. Freezing hope: Balancing realism and optimism in elective egg freezing. Ann Acad Med Singap. 2024 Jan 30;53(1):3-5. doi: 10.47102/annals-acadmedsg.2023428. PMID: 38920209.
10. Goldman RH, Racowsky C, Farland LV, Munné S, Ribustello L, Fox JH. Predicting the likelihood of live birth for elective oocyte cryopreservation: a counseling tool for physicians and patients. Hum Reprod. 2017 Apr 1;32(4):853-859. doi: 10.1093/humrep/dex008. PMID: 28166330.
11. Torra-Massana M, Miguel-Escalada I, Vassena R, Rodríguez A. Long-term storage of vitrified oocytes does not affect pregnancy and live birth rates: analysis of 5362 oocyte donation cycles. Reprod Biomed Online. 2023 Sep;47(3):103228. doi: 10.1016/j.rbmo.2023.04.019. Epub 2023 May 3. PMID: 37308341.
12. Rivas Leonel EC, Lucci CM, Amorim CA. Cryopreservation of Human Ovarian Tissue: A Review. Transfus Med Hemother. 2019 Jun;46(3):173-181. doi: 10.1159/000499054. Epub 2019 Apr 9. PMID: 31244585; PMCID: PMC6558345.