A breakthrough in research could make it easier for transgender men to have children
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There are several options for people who choose such treatments but want to have biological children someday. Adults can freeze their eggs, for example. But this usually involves stopping testosterone treatment and allowing menstruation to return, which can take several months. Hormone-based drugs are used to stimulate the ovaries to release multiple mature eggs, which are then collected during a surgical procedure that includes vaginal exploration. Babayev says the procedure can be especially difficult for transgender men. In addition, pausing testosterone therapy for many months can cause fatigue, mood swings, and sleep problems.
D. Ojeda, senior national organizer at the National Center for Transgender Equality in Washington, says many transgender men want to be able to create their own families without such disruption.
Options are even more limited for young people who want to start sex-defining medical care before they reach puberty – meaning they can’t freeze their eggs because they won’t catch them. ovulatory head. They can choose to have part or all of their ovaries removed and frozen, in which case the tissue could theoretically be replanted later – but some transgender men will choose that method. because it will increase estrogen levels in the body, says Kenny Rodriguez. Wallberg, a reproductive oncologist at the Karolinska Institutet in Sweden, who also witnessed Telfer present her work.
The alternative that Telfer and her colleagues are working on is to take eggs from the ovaries and mature them outside the body, in a laboratory. The team has had some success doing this with eggs taken from women’s ovaries, but they don’t know if they can mature eggs from the ovaries of people who have already started medical care. sex determination or not.
Telfer’s first task was to find out what effect testosterone therapy had on the ovaries, a matter of disagreement among clinicians.
To get a clearer idea, Telfer has partnered with two gender-affirmation clinics in the UK. Transgender men who took testosterone and were undergoing surgery that included removing their ovaries were asked if they wanted to donate them for research. In total, four people donated eight ovaries. The team compared the ovarian fragments with eight donated by women who had a caesarean section, who were of a similar age.
Transgender men’s ovaries are actually different – they have more collagen and less elastin, which makes the tissue stiffer. This stiffness can make it harder for the follicles to grow and release mature, ready-to-fertilize eggs.
Other options [to start a family] the more transgender we have, the better.
D Ojeda, senior national organizer at the National Center for Transgender Equality in Washington, DC
Telfer and her colleagues also evaluated 4,526 follicles from fragments of eight ovaries exposed to testosterone. About 94% of the follicles did not develop, compared with 85% in ovarian fragments from women who did not take testosterone.
The team then attempted to mature eggs from the ovaries of transgender men. Their method involves cutting the tissue around each follicle and then stretching it out in a dish. This appears to activate signaling pathways in the tissues that allow the follicles to release mature eggs.
It worked — researchers were able to mature a small number of eggs to the point where they were ready to be fertilized by sperm.
In theory, the team could use IVF to create embryos with eggs, and those embryos could be transferred into the uterus of a partner or surrogate. To do this in the UK, the team needed a license from the Human Fertilization and Embryology Authority. No such license is required in the US.
Ojeda says the technique will appeal to some transgender men: “More options.” [to start a family] the more transgender we have, the better.”
However, Telfer and her colleagues have not yet come this far. The first eggs the team had grown in the lab didn’t look completely normal. As eggs mature, they often undergo a special pattern of cell division that halves the number of chromosomes, ready for fertilization. The unused chromosomes are separated into a small cell called the polar body. The poles of the lab-grown eggs looked unusually large.
An extremely large body can be completely harmless. But the team is adjusting the composition of the liquid in which the eggs cook, just in case. More recent efforts have produced eggs that look more typical, Telfer cells. The team has matured about 10 eggs so far, but the project is still ongoing. “I would have liked to have our culture system stronger before trying to fertilize it,” says Telfer.
She wants to try the procedure in sheep before trying it in humans. Those experiments are expected to take place later this year. If they are successful, Babayev predicts that the technique will be successful in clinics. Most fertility treatments skip clinical trials before being widely available in clinics.
“Obviously the hard points will have to be worked out, but if she succeeds, I don’t think it will take long for the others… to do it very, very quickly,” Babayev said. But he is waiting for more evidence to believe the technique will work clinically. “I will have to meet a baby,” he said.
If it can be used to help transgender men carry healthy babies, the technique could also be useful in many other situations, says Rodriguez-Wallberg. Children facing cancer treatments that could damage their ovaries first can cause their organs to freeze, giving them a way to have children of their own as they get older.
Kutluk Oktay, a reproductive endocrinologist and fertility preservation specialist at Yale Medical School, says the method can also help others who are having trouble conceiving. Ovarian freezing may be an alternative to egg freezing: a single biopsy from the ovary may be preferable to the multiple steps involved in egg retrieval.
And while egg retrieval tends to produce about 10 eggs at a time, a small piece of the ovary can be used to make 100 eggs. “A little biopsy from the ovary… can be enough for a lot of babies,” Oktay says. “If we can figure out how to do this efficiently, it could be widely used.”