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There are several options for people who opt for such treatment, but want the opportunity to one day have biological children. Adults can freeze their eggs, for example. But that usually involves stopping testosterone therapy and allowing the menstrual cycle to return, which can take months. Hormone-based drugs are used to stimulate the ovaries to release more mature eggs, which are then collected by surgery that includes vaginal probes. The procedure can be especially disturbing for transgender men, says Babayev. In addition, pausing testosterone therapy for months can cause fatigue, mood swings and sleep problems.
Many transgender men would like to be able to start their own families without such disorders, says D. Ojeda, a senior national organizer at the National Center for Transgender Equality in Washington, DC.
The options are even more limited for young people who want to start nursing-affirming medical care before puberty — which means they can’t freeze their eggs because they won’t start ovulating. They may decide to have some or all of their ovaries removed and frozen, in which case the tissue could theoretically be reimplanted later – but few trans men would opt for the procedure because it would increase estrogen levels in the body, says Kenny Rodriguez-Wallberg. , a reproductive oncologist at the Karolinska Institute in Sweden, who also saw Telfer present his work.
An alternative that Telfer and her colleagues are working on includes taking eggs from the ovaries and maturing them outside the body, in the laboratory. The team has already had some success with eggs taken from female ovaries, but they did not know if they would be able to mature eggs from the ovaries of people who have already started gender-based medical care.
Telfer’s first task was to find out what testosterone therapy does to the ovaries, which is a matter of disagreement among clinicians.
To gain a clearer idea, Telfer has partnered with two gender affirmation clinics in the UK. Transgender men who took testosterone and underwent surgery that included removing the ovaries were asked if they wanted to donate them for research. A total of four people donated eight ovaries. The team compared ovarian sections with eight incisions donated by women who underwent caesarean sections, which were similar in age.
The ovaries of transgender men were really different – they had more collagen and less elastin, making the tissue more rigid. This stiffness can make it difficult for follicles to grow and release mature eggs ready for fertilization.
As many options as possible [to start a family] we have as trans people, the better.
D Ojeda, senior national organizer at the National Center for Transgender Equality in Washington, DC
Telfer and her colleagues also assessed 4,526 follicles from parts of eight ovaries exposed to testosterone. About 94% of follicles did not grow, compared to 85% in ovarian pieces in women who did not take testosterone.
The team then tried to mature eggs from the ovaries of trans men. Their method involves cutting the tissue that surrounds each follicle and then stretching it in a vessel. This appears to trigger signaling pathways within the tissues that allow the follicles to release mature eggs.
It worked – the researchers were able to mature a small number of eggs to the point where they are ready for sperm fertilization.
In theory, 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 so in the UK, the team needs to obtain a license from the Directorate of Human Fertilization and Embryology. Such a license is not required in the United States.
Some transgender men will like the technique, says Ojeda: “As many options as possible [to start a family] we have trans people, the better. ”
However, Telfer and her colleagues have not gone this far yet. The first eggs that the team matured in the laboratory did 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. Unused chromosomes separate into a small cell called the polar body. The polar bodies of the eggs that had matured in the laboratory looked unusually large.
The great polar body is probably completely harmless. But the team adjusts the content of the liquid in which the eggs mature, just in case. Recent attempts have resulted in eggs of a more typical appearance, Telfer cells. The team has matured about 10 eggs so far, but the project is ongoing. “I would like our cultural system to be more robust before attempting fertilization,” says Telfer.
She wants to try the procedure on sheep before trying it on humans. These experiments are planned to take place later this year. If successful, Babayev predicts the technique will be successful among clinics. Most infertility treatments bypass clinical trials before clinics offer them widely.
“It is clear that the shortcomings will have to be eliminated, but if it is successful, I think it will not take much time for others … to implement it very, very quickly,” says Babayev. But he is waiting for more evidence to be confident that the technique will work clinically. “I would have to see the baby,” he says.
If it can be used to help transgender men conceive a healthy baby, the technique could be useful in many other circumstances, says Rodriguez-Wallberg. Children facing cancer treatments that can damage their ovaries can freeze the parts first, offering them a way to have their biological children as they get older.
The method could also help others struggling to conceive, says Kutluk Oktay, a reproductive endocrinologist and fertility conservation specialist at the Yale School of Medicine. Ovarian freezing can be an alternative to egg freezing: taking a single biopsy from the ovary could be better than many of the steps involved in removing an egg.
And while taking eggs tends to result in about 10 eggs each time, a small piece of the ovary could be used to produce 100 eggs. “A little ovarian biopsy… might be enough for a lot of babies,” Oktay says. “If we can figure out how to do it effectively, it could be widely used.”