During the 34th annual meeting of the ESHRE (European Society for Human Reproduction and Embryology) – which took place in Barcelona last July, some reports on the subject of freezing eggs for non-medical reasons were presented and discussed in front of an audience of over 12 thousand experts from around the world. A practice known as ‘social freezing’ or elective freezing of the oocytes: it is a cryopreservation of the oocytes of women who want to ensure the possibility of a pregnancy in later life or in case of any problems with infertility.
We talked about this topic with Prof. Paolo Emanuele Levi-Setti, Director of the Humanitas Fertility Center, who was present at the conference with some collaborators.
Humanitas at the forefront of the Fertility Center
“The freezing of eggs is a great opportunity that is also offered to cancer patients before therapies that could permanently compromise their ovarian reserve and lead to a menopause with costs borne entirely by the public system – explained Professor Levi-Setti. For women who have to postpone pregnancy, this is a small but real possibility.
“During the meeting it emerged that our data – continued the professor – agree with those of colleagues in other countries that the lack of a ‘fair’ partner with whom to have a child is the main reason that directs women to this choice. In Italy, however, the lack of awareness on the subject of age and the probability of pregnancy is still enormous and it would be important that this could change, including through campaigns of reproductive education.
“The number of women requiring an elective freeze in Italy is lower than in other countries, although this practice has been tested and validated by Italian researchers. Humanitas was one of the first structures that gained experience in this field and presented data that convinced the international medical world to adopt this practice.
Social freezing: why do women freeze their eggs?
According to a qualitative study conducted by Dr. Marcia Inhorn, anthropologist at the University of Yale, on 150 subjects (114 from four clinics in the United States and 36 from three institutes in Israel) contrary to common thinking women choose to freeze their eggs not for study or career reasons, but for reasons related mainly to the lack of partners and stable relationships with whom to plan a life and a family together.
Until now, the medical literature has suggested that cryopreservation of oocytes was chosen to postpone or delay pregnancy in career women, while the results of the study suggest that the main motivation is instead the lack of a stable partner.
Interviews with 150 women revealed ten main reasons that led these women to freeze their eggs, in particular 85% of them said they did not have a partner at the time of freezing. The choice of the elective freezing of oocytes for career reasons was, instead, the least common.
Women, on the other hand, who stated that they had a partner at the time of the freezing (15%) showed different reasons for the choice, such as their man was not ready to have children, the relationship was too new or uncertain, a partner who refused to have children and finally a partner who has had multiple previous marital experiences.
In general, according to the anthropologist, the majority of women interviewed decide to freeze the eggs with the hope of finding a partner in the future, also considering the possibility of becoming a single mother with the sperm of a donor.
Estimates: egg freezing will boom in 2018
Elective oocyte freezing took off especially after the introduction of vitrification, a rapid freezing technology that reduces cells to a glass-like state in seconds and reduces the damage created by previous freezing methods to the microstructure of the egg.
In 2013, about 5,000 egg freezing cycles were carried out in the United States, but the estimate for 2018 is about 76,000 freezes, according to Pasquale Patrizio, co-researcher of the study. Given the significant increase, the facilities and specialists involved in this work need to know that the lack of a partner is the real priority for women who choose to cryopreserve their oocytes, an awareness that will have to reach even companies that offer freezing to their employees as “a legitimate insurance benefit”.
The right age for social freezing
In women under 35 years of age the cryopreservation of 10-12 oocytes is carried out, while for women over 35 years of age it will take about 20 oocytes to get one frozen for a reasonable chance of pregnancy. In particular, according to a study conducted in Belgium by Michel de Vos on 563 women who froze their oocytes between January 2009 and November 2017, the average age of those who froze their oocytes was 36.5 years with an average number of oocytes of 8.5. Of these women, however, only 7.6% had returned to ‘use’ them during pregnancy, after finding a stable partner.
Women who had frozen their oocytes at an average age of 36 years have returned to about 42 years and had a 33% chance of achieving pregnancy; in women who have frozen their eggs at an older age they will certainly have a lower chance of success.
The survival of the oocytes at thawing was 73.4%, a good percentage that demonstrated the good efficiency of the techniques and in 43 of the cases they proceeded to embryo transfer, obtaining 32.6% (14/43) of pregnancies.