A booklet published by the British Medical Association suggests that its staff should use the phrase "pregnant people" instead of "expectant mothers" in order to show sensitivity towards intersex men and trans men who get pregnant. The BBC's Siobhann Tighe spoke to one trans man for his view on the BMA's guidance.
It's impossible to get figures about how many trans men in the UK want to be pregnant, or go through pregnancy. The handful of gender identity clinics in the UK won't give out statistics, although one consultant psychiatrist says the figure is "tiny".
Only one transgender man in the UK, Hayden Cross, has spoken publicly about his pregnancy. Cross had hoped to freeze his eggs before completing his transition, but when the National Health Service refused to pay he decided to get pregnant with donor sperm and temporarily put gender reassignment surgery on hold.
I spoke to another trans man, Freddy McConnell, who has thought about what he might do if and when he wants his own children.
He's not ready to start a family yet, but if and when the time comes, he says carrying the baby will certainly be an option. He identifies as a gay man and has a partner who describes themselves as non-binary.
"That means that they don't identify as a male or a female - but they are on the masculine side of the spectrum," Freddy says.
Freddy, 30, made the physical transition from female to male four years ago with the help of testosterone. Even now he gets testosterone injections once every 12 weeks. He also had an operation performed in the States which removed his breasts and gave him a male, contoured chest.
But crucially he didn't have "lower" (genital) surgery, and that means that he has some options when it comes to having a family.
"I've always wanted kids and a family and I've thought about this a lot," he says.
"When trans men wants to have kids and they're on testosterone, they have to come off it. Then you'd have to wait for your menstruation cycle to kick in, and hopefully you'll be able to conceive. If you don't, it may be because you have a pre-existing fertility issue."
But stopping your testosterone is risky for a trans man because it could lead to gender dysphoria - described by the Terence Higgins Trust as an intense feeling of sadness, low mood and uncertainty.
Often this is what causes a person to transition in the first place, and for Freddy, it's a real concern.
"A lot of the changes that testosterone makes to your body are permanent. So, if you came off testosterone your voice wouldn't become high again and you wouldn't lose your facial hair," Freddy says.
"But the things that can change back once your system is running on oestrogen again is your fat distribution and muscle growth, and that could cause dysphoria and be challenging.
"If I was going to carry a baby that would worry me, because I really like the physical changes that testosterone has given me.
"It makes life a lot easier for me to be 'read' as male all the time, and I worry about losing that and the security it gives me in my identity."
Freddy acknowledges that there aren't many people like him in the UK.
"The trans community is small, the trans male community is smaller and then the number of trans men who've had babies is vanishingly small," he says.
This means that social media sites, particularly from America or Canada, are particularly useful when it comes to getting information, providing support and sharing feelings.
"People who've been through this experience talk about feeling worried, and they're frightened that they'll be judged," says Freddy.
"And so they look to the community itself for information. That's where you know that people won't talk in a way that's disrespectful and won't be shocked, and they'll use inclusive language."
So when it comes to the BMA advice about referring to "pregnant people" instead of "expectant mothers" Freddy feels it's uncontroversial and factually correct.
"What they're saying in this document is: 'If you're talking to a trans man or an intersex man about being pregnant, don't call him an expectant mother.'
"If you call me that, it's incorrect and it's going to make me feel like you're not talking about me, you don't see me, you don't get where I'm coming from and I wonder where it is going to leave me as a patient under your care. It signals rigidity and closed-mindedness.
"But it's really important to say we're not interested in redefining motherhood, or taking away that word. We're just trying to be seen."
Listen to Freddy on Woman's Hour
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