Foreign surrogacy leads to tragedy, is it feasible if the eggs are frozen?

Although egg freezing is more widely available in countries such as the United States, Canada, and Japan, it is not currently a good method.

Author: Xu Sijia, Kyoto University School of Medicine, Japan

Editor | Ju Siting Gao Peiwen

Recently, it was revealed that the famous actress Zheng Shuang had two children with a surrogate mother in the United States, which triggered public opinion. Ziguangge and CCTV News successively issued Weibo reminders: my country has banned surrogacy. Some discussions about assisted reproductive technology also became hot topics. Why do we need surrogacy? Isn't it better to freeze eggs?

Previously, famous actresses such as Michelle Ye and Xu Jinglei have confessed that they had frozen their eggs overseas. For the human tragedy caused by her colleague Zheng Shuang today, freezing eggs is undoubtedly a better choice for career women. However, freezing eggs is not a good choice, but just a compromise. At the 2020 Two Sessions, Dr. Sun Wei of the Second Affiliated Hospital of Shandong University of Traditional Chinese Medicine proposed that "citizens should be encouraged to marry and have children at the right age, and single women should be prohibited from freezing their eggs." At that time, it was only half a year away from the first human rights dispute case in my country caused by the "freezing of eggs" of single women, and the proposal was pushed to the hot search. "The issue of frozen eggs needs further popularization, and I hope to remind the public to marry and have children at the right age through this proposal." Sun Wei added in an interview. So, what are the considerations for Dr. Sun Wei's proposal? Is it reasonable? We can understand it from a technical point of view.
01

Freezing eggs to extend women's fertility period

Egg freezing is a method of preserving female reproductive capacity. It involves taking healthy eggs from women’s ovaries and storing them in a low-temperature environment to prevent them from aging with the body. They can be thawed and used when they want to have children in the future. This technology was originally used only for medical purposes. For example, for infertile couples who need in vitro fertilization (such as test-tube babies), if the man cannot be present to provide sperm or the sperm quality is poor on the day of egg retrieval, egg freezing becomes a remedial measure. Or for women with major diseases such as malignant tumors, systemic radiotherapy and chemotherapy often cause irreversible damage to ovarian eggs. Taking out and freezing the eggs before treatment can preserve the opportunity for female patients to have offspring. In fact, even women with healthy reproductive function are limited by age. Women have the function of ovulation after entering puberty. The ovaries on both sides of the uterus contain about 300,000 follicles in total. They are like contestants participating in an audition. There are only about 10 places each month for further development opportunities. After recruitment and selection, usually only one "dominant follicle" stands out, fully matures and "debuts" (releases an egg). If it happens to meet a partner (sperm), the egg will "transform" into a fertilized egg and develop a new life after reaching the uterine cavity.
Follicle development, ovulation, and movement trajectory after fertilization | dkfindout.com

Normal ovulation is one of the necessary conditions for fertility. From puberty to menopause, only about 400 follicles can mature and ovulate. The success rate of pregnancy also depends on the quality of the eggs, the endometrial environment where the fertilized eggs "implant", the hormone levels in the body, etc. These are all closely related to the "young degree" of ovarian function. In theory, women aged 20 to 28 have the most active ovarian function, relatively stable hormone secretion, good quality eggs, strong fertility, and are most suitable for pregnancy. After the age of 28, ovarian function begins to decline, and after the age of 35, the decline accelerates. The ovulation cycle may become irregular, the quality of the eggs gradually declines, and they are more sensitive to various physical and chemical stimuli during pregnancy. The incidence of miscarriage, embryo abnormalities and pregnancy complications increases. Due to various needs for delayed childbirth, more and more women with healthy reproductive functions have begun to seek help from frozen egg technology in recent years. When a woman fails to find an ideal partner, or is forced by work pressure to become a mother at the most childbearing age, freezing her eggs while the quality of her eggs is still good to create a reserve for building a family in the future seems to be a priceless regret medicine.

02

The egg freezing process consists of three steps: ovulation, egg retrieval and freezing

The three main steps of freezing eggs include: stimulating ovarian ovulation, obtaining eggs, and dehydrating and freezing. To ensure the success rate, as many eggs as possible (10 to 20) will be taken at a time for freezing eggs. But under normal circumstances, the ovaries can only produce one mature egg per cycle. This means that the ovaries must be stimulated with drugs to increase their output, usually by injecting hormones that have an ovulation-promoting effect. Hormone treatment lasts at least 1 to 2 weeks, during which time you need to go to the hospital frequently for ultrasound to observe the morphology of the follicles, draw blood to test estrogen levels, comprehensively judge the development of the follicles, and confirm the timing of egg retrieval. When a sufficient number of follicles have matured, the doctor, under the guidance of vaginal ultrasound, passes the egg retrieval needle from the vagina through the pelvic cavity to the ovaries, and extracts the oocytes one by one from the mature follicles. In order to ensure the precision of the operation, patients usually have to undergo anesthesia.

Ultrasound-guided egg aspiration from mature ovarian follicles | Santa Monica Fertility

After the absorbed egg cells are cleaned, the next step is to freeze them. Egg cells are rich in water. If they are frozen directly, the volume of water will expand when it freezes, bursting the cell membrane, and the ice crystals formed are more like countless sharp blades, damaging the cells, so the recovery rate of the eggs is very low. With the improvement of technology, a "vitrification freezing method" is now commonly used: the egg cells are placed in a high-concentration cryoprotectant solution, and the concentration difference is used to replace the water in the cells (30~50% of the water can be removed), and at the same time, a part of the freezing solution penetrates into the cells. After reaching equilibrium, the eggs are directly placed in a carrier and put into liquid nitrogen at minus 196°C.

During this rapid cooling, the freezing fluid mixed with the remaining water in the cells will form a viscous but ice-crystal-free "vitrified" state. The eggs can be safely stored for a long time in this state, and the recovery rate is about 80% to 90%. When the time is right for childbearing in the future, the eggs will be thawed, fertilized in vitro through in vitro fertilization and other technologies, and then transplanted back into the uterus. At present, the success rate of pregnancy using frozen eggs is not high, even lower than that of in vitro fertilization. Sun Wei revealed, "The current egg freezing technology is not mature. I have frozen eggs for couples who meet the requirements of laws and regulations, such as pathological reasons or special circumstances such as widowhood, but so far only one person has successfully become pregnant."

03

Freezing eggs has health risks and is expensive and needs to be paid out of pocket

At present, my country has very strict management on the application of egg freezing technology. Regular medical institutions cannot provide this technology to unmarried women or couples with normal fertility. However, the scope of egg freezing services in the United States, Canada, Japan and many European countries is relatively open. Taking Israel, a country with strong assisted reproductive technology, as an example, the country's laws allow women aged 30 to 41 to undergo up to 4 non-therapeutic egg freezing operations, with a total number of eggs not exceeding 20. On the premise of paying an annual storage fee (US$200 to 2,600), the frozen eggs can be kept until the age of 54.

Many countries allow commercial egg freezing services. The huge business opportunities have spawned a large number of medical tourism service agencies that aim to provide outbound egg freezing. Women who consider cross-border egg freezing are often financially well-off. In order to attract customers, many agents deliberately glorify the convenience of egg freezing in their publicity: such as "the entire process is painless and can be completed in half an hour of sleep", as if women can easily gain the right to control their future by having afternoon tea. In fact, when it comes to egg freezing technology, there are still many things that must be carefully considered from the physiological, psychological, and economic levels. Some online advertisements deliberately glorify the convenience and safety of egg freezing, which is misleading | Compiled by the author

Egg freezing should also be done when the quality and quantity of female eggs are most ideal before the age of 30, and the success rate of egg freezing is high. However, the possibility of natural conception is higher in this age group, and few people will consider such a long-term thing as egg freezing at this time. More people only think about freezing their eggs after the age of 35. At this time, as the ovarian function declines, the number of follicles produced by a round of ovulation induction treatment will decrease. If there are only a few, a second round or even multiple rounds of hormone treatment will be required to obtain enough eggs. The quality of eggs will also decline with age, and the number of eggs that survive freezing and successfully recover will therefore decrease.

Even if the egg is successfully revived, it still needs to go through many tests such as fertilization and implantation before it can lead to successful conception. Data analysis shows that the success rate of freezing eggs before the age of 34 is greater than 74%, while after the age of 40, it drops to less than 40%. It is worth noting that regardless of the quality of the eggs, egg freezing technology cannot avoid the risk of advanced pregnancy, and the best time to get pregnant is still as early as possible.

Ovulation-stimulating drugs are risky to the body. Under normal conditions, the ovaries only release one egg per month. Mature follicles secrete a large amount of estrogen, which is part of the periodic fluctuation of hormones in women's bodies and is involved in various physiological regulations. Frozen eggs require the ripening of more than ten or twenty follicles at a time. "The development of egg freezing technology requires human experiments. Human egg extraction requires ovulation-stimulating hormones that exceed physiological doses. Generally, 20 eggs are extracted at a time, which is two years of puberty. Five times means ten years. In order to ensure the success rate, the number of frozen eggs at a time will not be too small. People are old before they are 40 years old." Sun Wei vividly described the potential harm that egg freezing technology brings to women.

In addition, ovulation-inducing drugs may not only over-stimulate the ovaries and cause ovarian edema, but the total amount of estrogen secreted by multiple mature follicles is far higher than normal levels, which can cause a variety of side effects. The most common side effects are pleural effusion and ascites, which affect cardiopulmonary function. At the same time, due to the loss of a large amount of body fluids, the blood becomes concentrated and prone to blood clots, which can lead to stroke and pulmonary embolism in severe cases. Ovulation-inducing drugs may cause serious complications such as pleural effusion and ascites | Compiled by the author

Take the United States as an example. Each round of egg freezing costs an average of 50,000 to 60,000 RMB. If the effect of one round of ovulation induction is not ideal, a second or even more rounds of ovulation induction will be charged. After the freezing is completed, a storage fee needs to be paid every year to purchase the evaporating liquid nitrogen. The annual storage fee is about 3,000 to 7,000 RMB, and it is rising year by year. A very small number of companies with good welfare benefits, such as Google and Apple, will bear part of the cost for employees, but most of them are still paid out of their own pockets.

04

Egg freezing faces management and ethical risks, and opening up needs to be cautious

my country has clearly stipulated that "it is prohibited to implement human assisted reproductive technology for couples and single women who do not comply with the provisions of national population and family planning laws and regulations". And egg freezing technology belongs to the category of human assisted reproductive technology. Some people think that since egg freezing is technically feasible, women should be given the right to choose the time of childbirth. In the view of reproductive medicine professionals or competent departments, opening up this technology means encouraging women to give birth at an unsuitable age, and it also faces management and ethical risks, so it needs to be operated with caution. "At present, the marriage rate and population birth rate in my country are both declining. We still hope that more young people can get married and have children at the right age." Sun Wei expressed his concern about the possible consequences of lifting the ban on egg freezing. "Egg freezing belongs to a type of restrictive technology. According to relevant regulations, the marriage certificate, identity card, and birth permit are complete, and this technology will only be adopted if there are corresponding medical indications. The rash lifting of the ban may cause a waste of resources and give rise to illegal acts such as egg trading and surrogacy."

Human wisdom and enterprising spirit allow us to continuously create scientific miracles. However, one mistake that humans have repeatedly made is that while eager to enjoy the benefits brought by technology, they often realize the potential negative effects later, or they are lucky enough to pass the parcel. We once developed oil energy to our heart's content, and then realized that the large-scale emission of greenhouse gases caused global climate problems; we once coveted plastic products that were cheap and easy to use, but later found that they could not be degraded and had nowhere to be buried for hundreds of years, and invisible plastic particles were floating all over the ocean... The same is true for egg freezing technology. Although it can help many people overcome physiological and practical difficulties and experience the joy of being a parent, once it is separated from medical purposes, it will also bring many new concerns: the already severe low fertility rate in developed countries and developed cities may be further aggravated; in the absence of adequate medical knowledge, women are given the illusion that they can safely postpone childbirth, resulting in various complications of advanced pregnancy; under huge business opportunities, medical resources are mixed, reliable resources are used by the wealthy, and the poor may be used by criminals, "selling the womb" to become a surrogacy tool, and so on.

China has a huge population base, a vast territory, and a large gap between rich and poor regions. It is understandable that the competent authorities take a cautious attitude towards the opening up of technology and take precautions against management and ethical risks in advance.

05

Opposing egg freezing does not mean disrespecting women’s rights

Let's talk about the topic of women's reproductive choice. Some people regard egg freezing as "the science and technology that truly liberates women." Today's society gives women the opportunity to receive higher education and engage in high-tech jobs, but it is still a long way from true "equality." It can even be said that there will never be true equality. As mentioned before, the active window of female fertility is several decades shorter than that of men, and it takes at least a year from pregnancy to the time when the baby can leave and the woman is allowed to return to work normally.

If the economy is stable and the partner is considerate and can take the initiative to share the pressure, it is fine. Otherwise, the decline in quality of life will make many women discouraged from having children. They will tend to look for a more suitable partner, work hard for economic independence, or consolidate their career development. Many people may misinterpret this choice as "pretentious" or "career-minded", but in fact, female animals have the instinct to seek "security" for themselves and their offspring.

A "0 or more" phenomenon may illustrate this point from the side: in some countries with low birth rates, women are hesitant about getting married and having children, but once they have their first child, they are not very resistant to having a second or multiple child. The experience of having the first child gives women confidence to a certain extent. Self-control of the timing of childbearing through "freezing eggs" is an important sign of the independence and progress of modern women's consciousness. Everyone's choice must have its causes and consequences, and women's limited right to choose should be respected and protected. However, this medical decision about the health of oneself and the next generation should still be based on the necessary knowledge reserves to avoid facing health risks or challenges to social ethics.

When it comes to the use and popularization of a new technology, management needs to consider not only the feasibility of the technology, but also the social effects. But in the final analysis, technology only provides an option. It brings hope, but it cannot avoid risks. No matter how we choose to live, we can only achieve true happiness if we are true to our hearts and understand and take good care of our bodies.

References:

1.https://www.mayoclinic.org/tests-procedures/egg-freezing/about/pac-203845562.https://finance.sina.cn/china/gn cj/2020-05-25/detail-iirczymk3443349.d.html?cre=tianyi&mod=wpage&loc=7&r=32&rfunc=87&tj=none&tr=33.Petropanagos A, Cattapan A, Baylis F, Leader A.Social egg freezing: risk, benefits and other considerations. CMAJ.2015;187(9):666‐669. doi:10.1503/cmaj.14160524.https://www.asrm.org/resources/videos/ethics-webinars/webinars/ethics-webinar-planned-oocyte-cryopreservation/5.Xie Xing. Obstetrics and Gynecology[M]. 9th edition. Beijing: People's Medical Publishing House, 2018

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