What is Fertility Preservation?
Fertility preservation is the process of using ART (Assisted Reproductive Technologies) to freeze reproductive tissue, including ovarian eggs, sperm, embryos, and ovarian or testicular tissue to conserve fertility for future opportunities. The reasons why men, women and couples seek fertility preservation can be diverse; common reasons may include illnesses and medical treatments that compromise fertility status (such as chemotherapy and radiation), those undergoing gender-affirming medical or surgical transition and circumstances where individuals are not ready to start a family beyond an age where fertility naturally declines.
Egg freezing; also known as oocyte cryopreservation is becoming a more widely known and sought-after procedure for many women to preserve their fertility for the future. Ovarian egg quality and quantity naturally decline as a woman ages, and whilst egg freezing isn’t a fail-safe procedure to guarantee success, it offers many women a sense of control over their fertility and an alternative option in the future.
What Does an Egg-Freezing Cycle Look Like?
Consultation
After consulting with a fertility specialist to discuss your eligibility to undergo an egg retrieval cycle, you will be given a treatment plan that involves the use of hormonal stimulation to increase the development of several mature ovarian eggs that will then be retrieved as opposed to a natural menstrual cycle in which one egg naturally matures to ovulation. A thorough medical history and examination, complete with ultrasounds, blood work and genetic testing (if required) is usually the first step in undergoing an egg-freezing cycle.
Stimulation
The egg-freezing cycle will commence with day 1 of the menstrual cycle, the use of hormonal injections (gonadotropins) are self-administered subcutaneously daily for approximately 10-14 days, whilst regular blood tests and pelvic ultrasounds are conducted to monitor the degree of follicular development and rise in oestrogen. During this phase of the cycle, you may begin to feel bloating and mild discomfort in the lower abdomen as the follicles and ovaries enlarge, you may also feel some hormonal mood swings, sleep disturbances and changes in bowel movements.
Retrieval & Freeze
When the follicles reach a stage of maturation, the IVF nurses and your specialist will tell you to administer a subsequent injection; known as a trigger, which will determine the day of egg collection (approximately 36 hours later). The egg retrieval procedure generally takes 15-30 minutes and will be performed under general anaesthetic, during egg retrieval your specialist will use a transvaginal ultrasound and a needle which is used to aspirate the fluid from the follicles containing the oocytes. An embryologist then examines the follicular fluid, identifying the eggs, which will then be frozen and stored for several years until they are required.
What is the difference between egg freezing and vitrification?
Cryopreservation techniques use liquid nitrogen to freeze oocytes below -196 degrees Celsius to preserve their viability for an indefinite duration of time. The two types of cryopreservation techniques are slow freezing and vitrification.
Slow Freezing
Slow freezing is a traditional technique to freeze oocytes and embryos in IVF laboratories, in which cells would be frozen in slow, small increments (-40/-70 degrees Celsius) with the combination of cryoprotectant solutions to reduce the formation of ice crystals within the cells. Although slow-freeze techniques are useful for sperm preservation, over the years there have been poor survival rates of slow-freeze embryos and eggs after thawing; as a result, slow-freezing techniques have been replaced by vitrification.
Vitrification
Vitrification is an ultra-fast freezing method (a speed of 23000 degrees Celsius/minute), which prevents the water inside cells from crystalising to preserve cellular integrity. Vitrification thus also requires high doses of cryoprotectants. The egg survival rate with vitrification is approximately 90% and there is a trend towards higher implantation rates with vitrification-embryos, compared to slow-freeze embryos.
Refreezing Frozen Eggs & Frozen Embryo’s
Although it’s possible to refreeze thawed oocytes, it is not recommended due to the high risks of cellular damage. If you had previously frozen your eggs in the past and now wish to create embryos, those frozen eggs can be thawed and inseminated to create embryos and then re-vitrified if required.
What Age Can I Freeze My Eggs?
Too often women fall prey to the climate of fear and leap into an egg-freezing cycle after turning a certain age or after having a preliminary fertility blood workup and being told their egg reserve or AMH level (anti-mullerian hormone) is lower than “expected”.
There is technically no upper age limit for egg-vitrification procedures, however, most IVF specialists advise undergoing egg-freezing procedures before the age of 30-35 years for those seeking fertility preservation as egg quality generally declines beyond this age at a more rapid rate.
The success rates for conception are heavily correlated with the age at which the ovarian oocytes are frozen; for example, a woman who chooses to freeze her eggs at age 30, and uses them to conceive later in life at the age of 35, will have a similar chance of conception as a woman trying to conceive naturally in her 30’s.
How Does Chinese Medicine Help Prepare and Support an Egg Freezing Cycle?
In my clinical experience, very few GPs and IVF specialists emphasise the importance of preparing the body for an egg retrieval cycle, as much as they do for natural conception – for reasons that I’m not quite certain of?
It is the foremost priority within the practice of Chinese Medicine to adequately prepare the body pre-conception, pre-IVF or an egg-freezing cycle to not only regulate endocrine and ovarian function thereby increasing egg quality and the cohort of follicles attained; but importantly reduce the physiological stress that a medicated stimulation and egg-retrieval can have on the body.
A randomised control trial by Juhyun Kim et al. evaluated the effect of Acupuncture followed by IVF on the oocyte yield in women showing poor ovarian response and found that acupuncture significantly increased the number of retrieved mature oocytes in women aged 37 years and in those undergoing more than one controlled ovarian stimulation cycle, compared to IVF alone. Juhyun Ken et al. described that acupuncture is likely to enhance ovarian vascularisation and increase blood perfusion to the microenvironment of growing follicles to both enhance local growth factors and the responsiveness to ovarian stimulation.
Pre-Conception & Pre-Collection Preparation Timeline
We recommend patients prepare for at least 3 months before commencing ovarian stimulation, this is due to the duration of time required for ovarian follicular maturation (which takes approximately 85 days). This is a crucial time of rapid cellular growth and a time to optimise oocyte quality. In some situations, however, it is not possible to delay an egg retrieval/freeze cycle due to the necessity to commence prompt medical treatments, such as chemotherapy or radiation. Further discussions on the timeline of preparation can be had with your primary care physician and Chinese medicine practitioner for each unique case.
Some individuals may also be averse to delaying their IVF cycle due to fears of “rapid egg-reserve loss;” however, it is certainly not likely for a woman’s ovarian reserve to significantly differ over a 2-3-month period due to the normal processes of aging and this should not be a deterrent to adequately prepare and support the quality of oocytes for collection in the future. In a perfect scenario, the preparation period for natural conception, IVF or egg-freezing would commence 1-year out, as the whole process of folliculogenesis can take 355 days; however, acupuncture treatment and Chinese medicine therapy can be commenced at any stage of the egg-retrieval and freeze process.
Acupuncture Treatment Schedule for Egg Freezing
Elizabeth Cullen; Director of The Dao Health and Chinese Medicine Practitioner, has already discussed the research, dosage and timing of acupuncture treatment when completing a full IVF cycle with transfer in a previous journey entry; you can read more about that here.
However, in an egg retrieval and vitrification cycle I would recommend the following;
2-3 Month Preparation Period:
Weekly acupuncture treatments for 2-3 months preceding the start of the retrieval cycle. This may also include the incorporation of targeted antioxidant supplementation and/or Chinese Herbal Medicine.
Note: Chinese Herbal Medicine is discontinued from the start of hormonal injections to not interfere with the pharmacological actions of the IVF medications.
Stimulation Period:
Weekly acupuncture treatments are advised to continue from the start of the egg-freeze cycle, or day-1 of the menstrual bleed and the start of medicated stimulation.
Pre & Post Egg Retrieval:
Pre and post-egg collection treatments are often recommended within a 24-48 hour window to both enhance blood flow to the reproductive organs and reduce symptoms of discomfort such as post-collection bloating and cramping.
Recovery & Further Cycles:
It is not uncommon for IVF specialists to recommend several egg retrieval cycles to ‘bank’ a larger number of oocytes for vitrification. From a Chinese Medicine lens, this ‘back-to-back’ approach places an incredible demand on the body and causes rapid depletion of Kidney Jing. I would recommend taking at least a 2-3 months break in between cycles to repair homeostasis and replenish the body’s Qi and Blood, thereby regulating ovarian function and the response to the next medicated cycle.
Resources:
https://www.ivf.com.au/treatments/fertility-preservation/female-fertility-preservation
https://monashivf.com/services/preserving-fertility/egg-freezing/
https://www.healthline.com/health/egg-freezing-process#faq
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8158119/
