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There are a handful of options for those who choose this type of treatment but want an alternative to having a biological child one day. Adults can freeze their eggs, for example. However, this usually involves stopping testosterone treatment and allowing the menstrual cycle to return, which can take months. Hormone-based drugs are used to stimulate the ovaries to release multiple mature eggs, which are then collected in a surgical procedure involving a vaginal probe. The procedure can be particularly painful for transgender men, Babayev said. Also, stopping testosterone therapy for several months can lead to fatigue, mood swings and sleep problems.
D., senior national organizer of the National Center for Transgender Equality in Washington, DC. Ojeda says many transgender men will be able to start their own families without such barriers.
Options are even more limited for adolescents who want to start gender-assisted medical care before they reach puberty — which means they cannot freeze their eggs because they have not started ovulating. They may choose to remove or freeze part or all of their ovaries, in which case the tissue could theoretically be replaced later – but some trans men will choose that method because it will increase estrogen levels in the body, says Kenny Rodriguez – from Walberg, Sweden. A reproductive cancer specialist at the Karolinska Institute who watched Telfer present his work.
The options that Telfer and his colleagues are working on include taking eggs from the ovaries and maturing them in the lab, outside of their bodies. The team has already had some success doing this with eggs taken from women’s ovaries, but they didn’t know if they would be able to mature eggs from ovaries in people who have already begun gender-specific medical care.
Hard ovary
Telfer's first task was to find out what testosterone therapy does in the ovaries, which is a matter of controversy among physicians.
To get a clearer idea, Telfer has teamed up with two gender confirmation clinics in the UK. Transgender men who were taking testosterone and had surgery to remove their ovaries were asked if they would like to donate for the study. In all, four people donated eight ovaries. The team compared the piece of ovary to eight sleevers donated by women undergoing caesarean section who were the same age.
The ovaries of transgender men were really different — they had more collagen and less elastin, which makes the tissue stronger. This firmness can make it difficult for follicles to grow and prepare for mature, fertilized eggs.
More options [to start a family] As we trans people, well.
De Ojeda, Senior National Organizer, National Center for Transgender Equality, Washington, DC
Telfer and colleagues evaluated 4,526 follicles from eight testosterone-exposed ovarian fragments. About 94% of follicles did not grow, versus 85% of women who did not receive testosterone.
The team then tries to mature eggs from the ovaries of trans men. Their procedure involves cutting the tissue around each follicle and then stretching it to a plate. It appears to trigger signaling pathways between tissues that allow follicles to release mature eggs.
It worked – the researchers were able to mature a small number of eggs where they were ready to be fertilized by sperm.
Theoretically, the team could use IVF techniques to create embryos with eggs, and those embryos could be transferred to the uterus of a partner or surrogate. To do this in the UK, the team must obtain a license from the Human Fertilization and Embryology Authority. The United States does not require such a license.
The strategy would appeal to some transgender men, Ojeda said: “More options [to start a family] The more trans people we have, the better. ”
Although Telfer and his colleagues have not yet gone that far. The first eggs that the group matures in the lab do not look completely normal. When eggs mature, they usually go through a special type of cell division that halves the number of chromosomes, preparing them for fertilization. Chromosomes that are not used are broken down into smaller cells called polar bodies. The polar body of the mature egg in the lab looked unusually large.
A large polar body can be completely innocuous. But the team is changing the content of the liquid where the egg matures, just in case. More recent efforts have resulted in more common looking eggs, cell telphers. The team has matured about 10 eggs so far, but the project is ongoing. “I want to strengthen our cultural system before trying to fertilize,” Telfer said.
He wants to test the method in sheep before trying among people. These tests are scheduled for later this year. If they succeed, Babayev predicts that the strategy will begin in clinics. Most fertility treatment clinics bypass clinical trials before they are widely offered.
“Obviously problems have to be solved, but if he succeeds, I don't think it will take long for others … to implement very quickly, very quickly,” Babayev said. But he is waiting for more evidence to confirm that the strategy will work clinically. “I need to see a baby,” she says.
If it can be used to help transgender men conceive healthy babies, the strategy could be effective in many other situations, says Rodriguez-Wahlberg. Some parts of babies that are facing cancer treatment that can damage their ovaries may be frozen at first, providing a way for them to have their own biological offspring as they grow up.
Kutluk Oktay, a reproductive endocrinologist and fertility conservationist at the Yale School of Medicine, says the procedure can help others fight for pregnancy. Ovarian freezing may be an alternative to egg deposit: taking a single biopsy from an ovary may be preferable to the many steps involved in egg recovery.
And when the egg recovery results in about 10 eggs at a time, a small portion of the ovary can be used to produce 100 eggs. “A little biopsy from the ovaries … may be enough for many babies,” Okte said. “If we can figure out how to do it efficiently, it can be used extensively.”
