The egg cell is vital for female fertility and, at 0.1 mm, the largest of human cells. A newborn baby girl is born with about a million immature eggs in her ovaries, and they form an unique egg reserve. Throughout a woman’s lifetime, the majority of her eggs are inevitably wasted due to a natural process of growth and degeneration of eggs called apoptosis. By the time she reaches puberty and has her first period, she has roughly 400,000 eggs left. Some 300–500 of her eggs make it to ovulation during her fertile years. Of these, only a few become fertilised and lead to pregnancy and childbirth. A woman’s fertility ends several years before the beginning of the actual menopause, which for Finnish women is around the age of 50–51 on average. This means that even a regular menstrual cycle is no guarantee of fertility as a woman ages.
Human reproduction is far from equal when comparing women to men. Men’s testicles produce new sperm almost throughout their life, but women have a limited period when they are fertile. On average, a woman’s fertility begins to decrease after her 30th year, and this reduction becomes faster after her 35th year. However, there is great individual variation. Fertility decreases with age as the number of eggs drops and their quality deteriorates. At the same time, the risk of miscarriage and chromosome abnormalities in the foetus, such as Down syndrome, increases.
Ovarian reserve, i.e. a woman’s remaining egg supply, can be tested with a gynaecological ultrasound scan, in which the number of follicles in a woman’s ovaries is calculated (known as Antral Follicle Count or AFC). The small immature follicles in the ovaries secrete the antimullerian-hormone (AMH). By studying AMH content, we can also estimate ovarian reserve. By also taking the woman’s age into account, we can make a reasonably good assessment of her fertility.
The freezing of eggs for medical reasons to preserve fertility has been a normal procedure for years; for example, before starting cancer treatments that may damage the ovaries. There are other medical reasons too, such as severe endometriosis or certain autoimmune diseases, whose treatment may prematurely reduce ovarian reserve. There may also be other reasons besides medical ones to preserve fertility. By freezing her own eggs before turning 35, a woman can give herself extra time, for example, to find a suitable partner and prolong her chances of having her own genetic child. Even women in a relationship may have various reasons to consider social egg freezing. Please note, however, that the purpose of social freezing is not to treat women when they are close to menopause, but to give them extra time to start a family.
Thinking about social freezing may raise all kinds of thoughts and emotions, some of them conflicting. Many people considering it may feel guilty for not being ready to have a child yet, although the reasons for postponing it are usually perfectly understandable and justified. Some women are not sure whether they will ever want to have children. Yet others have experienced great disappointments when looking for a partner to have children with. Sometimes, an existing partner may be hesitant about becoming a parent. Talking with a psychologist can be a great help in dealing with your feelings and outlining your goals for the near future. Social freezing may give you assurance that you have done everything in your power to maximise your chances of having a child when your situation in life is more suitable for a baby.
Social freezing requires about two weeks of hormone treatment and egg retrieval, the same as in vitro fertilisation. The first step is for a doctor to examine the functioning of the woman’s ovaries and her ovarian reserve. The doctor will also explain in detail the different steps involved in social freezing. Women considering social freezing will also meet with Ovumia’s psychologist, who will discuss the psychological aspects with them. During this counselling, they will also go through the Finnish legislation regarding fertility treatments (Act on Assisted Fertility Treatments and Act on the Medical Use of Human Organs and Tissues).
The woman will meet her doctor together with her partner. The frozen eggs will be thawed and fertilised with the partner’s sperm. If the fertilisation and embryo development are successful, the embryo is transferred to the womb within 2–5 days of fertilisation. It is also possible for single women to use their frozen eggs, in which case donor sperm from a sperm bank will be needed. The embryo can be transferred within the woman’s own, well-functioning menstrual cycle, but usually hormone treatment is required to prepare the uterus for pregnancy. Similarly to in vitro fertilisation, any extra embryos of good quality can be frozen for later use.
The freezing of embryos is a process that has been applied for a long time in fertility treatments and a laboratory technique that has been studied extensively. The freezing of eggs is a more complicated process than embryo freezing because the egg is large and the unique genetic information it contains is more fragile than that of an embryo. Thanks to the extensive development work on freezing methods, in vitro fertilisation treatments with frozen eggs are now offered routinely.
Egg freezing is not “rocket science”, but requires dedicated efforts from the fertility treatment laboratory and continuous updating of skills to ensure a high level of treatment results. The freezing method used is called vitrification. It involves the use of protective agents to prevent the formation of ice crystals, which are harmful for cells, and the ultra-rapid freezing of the eggs in liquid nitrogen to a temperature of -196° Celsius. The eggs are then stored at this temperature in a state of arrested metabolism. The length of the storage period does not affect the end result of the treatments.
The biggest factors in the success of this treatment are the woman’s age and how well her ovaries work at the time of freezing. At clinics where egg freezing is an established practice, the results are comparable to the results of in vitro fertilisation treatments.
Ovumia has had an egg bank for donor eggs in use since the summer of 2015. Based on the treatments carried out, the treatment results are estimated to be similar to corresponding treatments using fresh donor eggs. Of course, it is important to remember that we cannot guarantee a pregnancy or birth with any certainty, even with social freezing.
Please don’t hesitate to contact us at Ovumia and make an appointment. If you are interested in social freezing or have any questions about fertility, Ovumia’s Fertility Inspection, alone or together with your partner, is a good place to start.
Medical Director in Helsinki, M.D., PhD, MBA, Specialist in Obstetrics, Gynaecology and Reproductive Medicine
M.D., Ph.D, Specialist in Obstetrics and Gynaecology
Medical Director in Jyväskylä, M.D., Specialist in Obstetrics and Gynaecology
M.D., Specialist in Obstetrics and Gynaecology
M.D., Specialist in Obstetrics and Gynaecology
Medical Director in Tampere, M.D., Ph.D, Specialist in Obstetrics and Gynaecology and Reproductive Medicine
Chief of Development, M.D., Ph.D, Specialist in Obstetrics and Gynaecology and Reproductive Medicine
M.D., Ph.D, Specialist in Obstetrics and Gynaecology and Reproductive Medicine
M.A., Fertilisation treatment biologist (ESHRE certified), Laboratory Director
M.A., Senior Embryologist, Laboratory Development Director, PGT specialist
M.A., Fertilisation treatment biologist in charge
MSc, Fertilisation treatment biologist (ESHRE certified)