When Juliet Swire gave birth to her third son in February 2014, doctors told her not to tell anyone he’d been born. She didn’t announce Jack’s arrival for weeks – not even to close family and friends.

Jack was born with both male and female anatomy, with ovarian and testicular tissue, and genitals that could belong to either a boy or a girl. He has one of at least 40 congenital variations, known collectively as disorders of sexual development (DSD), or intersex traits. It was months before Juliet and her husband, Will, were told Jack’s specific diagnosis, of mixed gonadal dysgenesis. While they waited, all his parents knew was that Jack’s sex couldn’t be determined at birth, and that their doctors needed time to assign it.

“One of the beautiful parts of having a baby is being able to share the joy that this tiny, newborn person has entered the world,” Juliet says. “We could have announced that our baby had been born with complications that mean we don’t know if he’s a boy or a girl. But the doctors took that away from us without any explanation.” By encouraging them to keep Jack a secret, the doctors made them feel there was something shameful about his condition, she says. “It set the precedent for how other people were going to perceive it.”

I'd assumed that XX is a girl and XY is a boy. People don't know there are variations, so when they occur it's freakish

Jack’s specific diagnosis is rare, but being born with a blend of female and male characteristics is surprisingly common: worldwide, up to 1.7% of people have intersex traits, roughly the same proportion of the population who have red hair, according to the Office of the United Nations High Commissioner for Human Rights. The British charity DSD Families estimates that around 130 babies born in this country each year need investigations before their sex is assigned. Other people may have problems with their hormones that aren’t visible at birth.

Jack’s parents knew he was different before he was born, when a routine scan couldn’t determine if he was a boy or a girl. Juliet was referred to a consultant at the local hospital, followed by meetings with geneticists and neonatologists, blood tests and an amniocentesis. She was told her baby was genetically male, but that this didn’t necessarily make him a boy. “It was very hard. I’d just assumed that XX is girl and XY is boy,” Juliet says. “Because people don’t know there are variations, when they occur it’s a freakish thing. But actually, he is just a normal child.”

Bouncing around the living room of their home in the West Midlands, Jack looks completely ordinary. With mousy, curly hair, a runny nose and a toothy smile, he clambers over Juliet and chucks a green football at me, oblivious to what his mother is telling me.

“My entire pregnancy, I’d worried that I wasn’t going to be able to love my baby because it wasn’t a he and it wasn’t a she,” she recalls. But when Jack was born, he was blue and floppy. “Although it was awful at the time, it was the best thing that could have happened: I would have done anything to have made sure he was breathing again.” Her eyes fill with tears. “Quite quickly, he was crying. The relief was unbelievable. He was a baby and he needed feeding. Making sure that he was cared for was my priority, not poking around in his nappy.”

Then someone from Bounty (a baby merchandising company whose sales reps, controversially, are allowed on maternity wards to collect mothers’ details for marketing purposes and to sell photographs) paid her a visit when Jack was a day old; Will had just gone home to rest. She told Juliet she was there to take pictures of the baby: was it a boy or a girl? “We had no idea. Because I was tired and emotional, I just said, ‘Oh, he’s a boy.’ She then got a blue blanket and a blue teddy and a label that said ‘I’m a boy’, and put it on him to take photographs. She never even asked permission to be there. When she left, it was the biggest meltdown I’d had yet.”

The Swires say they still feel let down by the team who were supposed to be looking after them – not just the photographs, but being advised by doctors not to announce Jack’s birth, by the fact their midwife didn’t read Juliet’s notes before delivering him, by the fact other people working in the hospital were not stopped from asking them the sex of their new baby. Most of all, they felt isolated by how little medical professionals knew about disorders of sexual development. “The midwives have never heard of it. Our GPs have never heard of it. A&E doctors don’t know, nurses don’t know. It’s rare – but it’s not that rare.”

***

When it comes to wider public awareness of what it is like to be intersex, there is almost none. While the transgender rights movement gathers momentum, and a growing number of people are choosing to identify as “non-binary” – neither male nor female – those who are born outside the physical categories of male and female sex have found it more difficult to have their voices heard. They are atomised, connected only by condition-specific support groups rather than united under a broader intersex umbrella. The terminology itself is fiercely contested: some find the “disorders of sexual development” label deeply offensive, as it implies a defect rather than a natural state of being. Others, often parents like Juliet, prefer DSD and reject the label intersex as “negative and sensationalising”.

But a movement is beginning to emerge. Social media has presented fresh opportunities for older people to connect, seeing their difference as variations to be embraced rather than defects to be corrected. A new generation is campaigning so that children born like them aren’t forced into biological categories: either socially, by being made to identify as male or female on birth certificates and other official paperwork; or on the operating table.

The sex on a baby’s birth certificate is generally based on what their genitals look like, but this is only part of what makes a boy a boy and a girl a girl: there are also the ovaries or testes, the mix of hormones, the pattern of the chromosomes. Variations in any of these physical characteristics means bodies don’t fall into the binary categories that make up conventional sex definitions. Sometimes these variations can lead to medical complications, such as infertility or hormone imbalances, but most intersex babies are physically healthy. Not all have ambiguous genitalia, and some don’t discover their condition for years: girls with complete androgen insensitivity syndrome (CAIS) might not realise they are genetically male until they reach their teens and their periods don’t arrive.

“Normalising” surgery to make very young children look more typically male or female has been standard practice for decades. Malta became the first country to outlaw non-consensual medical interventions on intersex people (including those too young to give informed consent) in 2015. In January this year, the Chilean government issued guidelines to doctors opposing corrective surgery, allowing them to refuse a parent and not face legal consequences. The parents of an adopted intersex boy are currently suing doctors and social services in South Carolina in the United States for removing his penis and testes at 16 months, even though it was not medically necessary – potentially opening the floodgates for future litigation. But in the UK, US and Australia, there is currently no national law or guidance on corrective surgery: it is up to the individual hospital or practitioner to decide.

For the Swires’ doctors, there was no question as to whether or not Jack should have surgery. “It was assumed that we would do certain things the whole way along,” Juliet says. “We weren’t given an option.” Their neonatologist was “very confident that operating on children to make them more normal was the right thing to do. His confidence gave us confidence.”

One doctor described it as your baby being born with an extra nose on their face. Would you leave it there, or fix it?

After blood tests to confirm Jack’s genetic makeup and assess his hormones, and scans to look at his internal organs, it was decided that he should be assigned male. But the scans turned out to have given a false result: when he was nine months old, Jack was discovered to have a uterus and fallopian tubes, albeit ones that could never produce children. These were immediately removed, because doctors said they posed a high risk of malignancy and cancer; he has had two further operations that will make him pass more easily as male. (“If you imagine labia – they stitched that together,” Juliet explains. “They called it ‘zipping it up’.”) At the same time, they corrected Jack’s hypospadias, a condition that meant his urethra opened at the base of his penis, moving it further up so he could pee more like a boy. He has further operations to come.

The pressure of making choices on Jack’s behalf has been tough on the Swires. “I’m confident we have made the right decision,” says Juliet. “I don’t see him as strikingly different to his brothers. But there are flashes of doubt – generally around surgery days, when we are making the decision to make him a certain way. Based on all the information we’ve been given – but still, we are the ones making the decisions.” She adds: “One of the doctors described it to us as your baby being born with an extra nose on their face. Would you leave it there, or would you fix it?”

As if it were a deformity?

“Yes. Cleft lip – that’s essentially a cosmetic thing; would you repair it? Yes, you would. It is a defect, it’s not how it’s meant to look.”

The Swires’ decision was made without the support of psychologists or counsellors, or even family. Juliet gave up her job in childcare to take care of Jack full time, as even very close relatives have found his condition hard to accept: she says she can’t trust them to change his nappy without making him feel uncomfortable.

Juliet looks at Jack as he vaults across the sofa. “There is no option to be genderless in this society,” she says. Would it have made a difference if there were? “It might have done,” she replies immediately. “If you could say you could be male, female or something else, and that was a normal thing to do in unusual circumstances, then it might have made a difference. But you go with the majority, you go with what you think is right. While he is this young, I am the person making those decisions and I’ve got to be confident about them. If he did identify as female as he gets older, I’d want him to know I was confident that I was doing the right thing for him every step of the way.”

Dawn Vago: ‘My parents were told not to tell me.’ Photograph: Sophia Spring for the Guardian

Dawn Vago has grown up with the consequences of having surgery to “correct” an intersex variation as a child. Now 35, she is genetically male but has always looked entirely female. She has CAIS, complete androgen insensitivity syndrome: her body has XY chromosomes but is unable to respond to male sex hormones, so she developed female genitalia. Internally, she was born with testes instead of ovaries, and no uterus.

Warm and self-assured, Vago lives in Cheshire when she’s not working as an entertainer on a cruise ship. She is one of only a few British intersex people prepared to speak publicly on the issue. “My parents were told not to tell me, that I wouldn’t understand and I wouldn’t fit into society if I knew the shameful secret about myself,” she says. “They wanted me to live an open and honest life, so they told me when I was five years old.” Dawn’s parents were told by doctors that she would get cancer if her testes weren’t removed, so she had a full gonadectomy aged eight. “They said I would not survive puberty if I did not have the operation, and that wasn’t true.”

The advice regarding the cancer risk has since changed; it is now thought to be minimal and to affect adults, not children – meaning the decision to remove the testes or ovaries can be left until people are old enough to make it themselves. Vago says the synthetic hormones she now has to take have left her with a higher risk of developing breast cancer than she would have had of developing testicular cancer. “Because my body wasn’t receiving the healthy hormones that it would have produced, and through mismanagement of my synthetic hormones, my body started to deteriorate.” By the time she was in her mid-20s, Vago had developed osteoporosis and broken 11 bones. She believes choices about medical intervention, be that surgery or hormones, should be left until the individual is old enough to make an informed decision.

Doctors said I’d never find a man to love me and have my own family. I adore that I'm married and starting a family

Vago is living proof that intersex people can live successful lives while being open about being born outside traditional male and female categories. We’re speaking a few days after she has had a bid to adopt approved. “Doctors told my parents that I would never find a man who would love me, and I would never have my own family. I absolutely adore the fact that I am married and about to start a family. It proves you control your own life.”

Like the Swires, Vago’s family learned to live in a state of isolation. Doctors had told them their child was totally unique: there were no other families to share experiences with, no support group to join. It wasn’t until she was 22 that she found out she wasn’t alone. “I was very angry at the time, because I’d spent the last 22 years not knowing where I fitted into society – only to find out there was a huge community out there that I could have connected with.”

Dawn is now co-director of IntersexUK, a campaign group founded in 2011 to end stigma around intersex variations, and to fight for equality and protection of intersex people. Top of its list of 33 demands is: “To put an end to mutilating and ‘normalising’ practices such as genital surgeries, psychological and other medical treatments through legislative and other means.” It is one of several British organisations now lobbying for corrective surgery to be outlawed in the UK. In March, IntersexUK and other campaigners met with members of the Scottish parliament to make their case.

“We promote bodily autonomy and fully informed consent,” Vago explains. “The surgeries that are happening on intersex children are for the most part cosmetic. Most are about making the child conform to society’s ideology of what male and female is. The child’s body is the child’s body to decide what they want to do with themselves.” IntersexUK doesn’t suggest an age when it considers children old enough to give informed consent; British transgender children aren’t offered the option of gender reassignment surgery until they are at least 17.

“It’s akin to female genital mutilation, or as we term it, intersex genital mutilation, IGM,” Vago says. “And it is happening in the UK right now.” On 9 June, IntersexUK was instrumental in getting the UN Committee on the Rights of the Child to reprimand the UK for allowing “medically unnecessary surgeries and other procedures on intersex children before they are able to provide their informed consent”. The report found that such surgery “can cause severe physical and psychological suffering”.

In 2013, the special rapporteur to the United Nations Human Rights Council’s report into torture and other cruel, inhuman or degrading treatment called on member states to ban “forced genital-normalising” surgery. Last year, the Council of Europe’s Commissioner for Human Rights demanded an “urgent” end to “unnecessary medical treatment and surgery of intersex individuals without their consent”. In March, campaigners Joe Holliday and Ela Xora chained themselves to the Houses of Parliament and called for a UK government inquiry into corrective surgery.

“It is becoming increasingly likely that the government will have to move on this, just as they moved on the gender recognition act and the same sex marriage act,” says Dr Jay Hayes-Light, director of the UK Intersex Association, which lobbied MSPs alongside IntersexUK earlier this year. “This is long overdue.”

Born intersex and given medical treatment to assign him female, a sex he didn’t want to be, Hayes-Light has lived as a man since he was 19. Like Vago, he is campaigning for the right not to choose a gender on birth certificates, as the non-binary movement is. “You can’t create a woman with a scalpel and a tablet,” he says, plainly. “Medical practitioners view intersex as something that needs to be fixed. We are regarded as deformed, somehow in deficit anatomically, and therefore the way to fix it is to cobble us together into what they deem to be an acceptable format, instead of allowing us to exist in society.”

Hayes-Light recognises that it is often the fear of social rejection that motivates parents to choose surgery for their children; they just want them to be “normal”, and not forced to be the vanguards of a political movement. “The opinion of other people should not be a catalyst, but it does matter,” he says. “Parents need help, guidance and advice to deal with it.”

***

When Ruth Spencer gave birth two years ago in the East Midlands, the midwife told her she had a boy. He was checked by the paediatrician; Ruth and her husband were given the paperwork for his birth certificate. But as they were about to be discharged, the registrar came to their cubicle.

“She asked where the birth certificate letter was. I said it was in the car – we were getting ready to leave – and she said, ‘I’m sorry, you’re not going to be able to leave, because we don’t know if your baby’s a little boy or a girl.’” With only curtains to separate them from the rest of the ward, everyone around them could hear.

“It was our first child, it was such an amazing experience – and then they just pulled the rug out from beneath us. We told family we’d had a boy, we had named him. Luke was born at 5.30am, and they didn’t say anything to us until 4pm.” It was another two days before Luke had an ultrasound; while the Spencers waited, each new shift of midwives asked them if they’d had a boy or a girl. “Such simple things could have made it so much easier,” Ruth remembers.

Luke is now two and the family still don’t have a diagnosis. Genetically male, Luke was born with a small penis, undescended testicles and other variations that mean he has a DSD. “At some point in the not so distant past, boys born with the genitalia our son had would have been reassigned female,” says Ruth.

He has had two operations: one was medically necessary to preserve his fertility; the other was performed to avoid discomfort for him in the future, Ruth says. Choosing to go ahead with the procedures wasn’t easy. “All my trust is in these doctors and yet there are such conflicting opinions on what should be done. We were of a mind to leave all treatment for as long as possible, so that we could involve him. No one ever asked us, are you OK with this? It was just, this is what we’re going to do. Abnormality, disorder, problem – these are all the words that are thrown at you. It makes it out to be something wrong. It might not be the standard, but it’s still nature.” She sighs. “It’s such a huge decision to make.”

In theory, parents like Ruth and Juliet should be assigned specialist psychological support to help them make these decisions, but provision around the country is patchy and underfunded. Even where experienced psychologists are available, they are stretched.

Dr Julie Alderson, a clinical psychologist at University Hospitals Bristol NHS Foundation Trust, has been working with parents of children with DSD since the late 1990s. Almost every family she meets has felt ashamed or embarrassed after their treatment on the maternity ward, she tells me. While tests and surgical techniques have changed over the course of her career, she still hears parents describing “the same problems, the same worries, the same purgatory of time” as they did 20 years ago.

In Bristol, Alderson works alongside an interdisciplinary team of surgeons, geneticists and endocrinologists. Her role is to offer families space to think. “All of the very well-meaning, passionate and caring healthcare professionals involved have got strong views about what’s the right thing, and they present options for all kinds of treatment in a way that is leading, in the nicest possible way. People don’t feel that they are making a decision: it’s very easy to accept what’s offered and what feels like it’s being recommended. I’m saying to the families, what are you actually hoping for for your child? And how much will surgery deliver that?” Parents may hope surgery will allow their children to be more comfortable in their bodies, but a child raised to have a positive identity about being different might be more secure than one who has scars and needs regular hospital checkups, she argues.

The surgical team at Bristol Children’s Hospital who work with Alderson know that an emerging human rights campaign is focusing on their work. “We’re doing it less and less,” says consultant paediatric urologist Guy Nicholls. “We have become more mindful that, whatever surgery you do, you are preserving fertility for the future and not doing something early for a cosmetic reason which may then jeopardise function in the future. Any surgery for this sort of problem is a little bit of a compromise – you try and include the parents and manage their expectations, making them realise we can’t achieve normality, no matter how much we want to or how hard we try.”

I kept looking at my baby thinking, this can’t be. I hadn’t heard of intersex. If I had, I’d have been more prepared

Nicholls’ words may be couched in the language of “abnormalities” and “problems”, but he says that’s how most parents view disorders of sexual development. “Surgeons are under constant pressure from parents to ‘sort it out’. They want their child to be normal. They want the problem to go away. That’s absolutely understandable. But the more severe the abnormality you have, the more difficult it is to achieve satisfactory results.”

If surgery is successful enough for people to pass as their chosen sex without any complications, they don’t want to broadcast that they’ve had it, Nicholls points out. “We don’t tend to hear from the people who do very well. You hear a lot from the people who have had a lot of problems.” These are problems largely with sexual function, and a need for further surgery as a child grows older. “They relate to procedures that were done some time ago, which are probably slightly different from what many of us are doing now. We like to think we are causing less scarring, fewer problems for the future – but we won’t know for 20 years.”

Mark Woodward, a paediatric surgeon and urologist who works alongside Nicholls, agrees. “A small group of people who have had surgery and are understandably unhappy will detract from a genuine picture of a whole load of people not being unhappy. It’s tricky to write off surgery on the basis of that.”

Surgery in infancy is more straightforward than later in life, Woodward argues: tissues are easier to operate on and heal better, and the distances to bridge are smaller. Performing an operation before a baby can remember the trauma spares them the distress of going through it as a teenager. Plus, no one has expertise in operating on young people old enough to give informed consent.

“If everyone is too worried about doing the wrong thing by these children now, and we say, ‘Let’s leave it until they’re 15,’ who’s going to do the surgery? It isn’t going to be a paediatric urologist. It’s not like there is a generation of surgeons out there who will have had any experience of this very niche surgery. I just worry that people will become too scared to do anything for fear of doing the wrong thing, and then be putting off a problem that will be a real surgical challenge. Surgeons are getting less experienced, if anything.” While the Swires’ doctors did not hesitate to recommend surgery, others are increasingly reluctant.

There is little data on the wellbeing of intersex children who don’t have surgery, with not enough studies and too few cases for meaningful conclusions to be drawn. Deciding not to operate on a child comes with some consequences, just as choosing surgery does: raising a child with ambiguous anatomy in a world where a binary understanding of sex still rules is not easy.

At the moment, both options are available to British parents: to refuse or opt for surgery. And while a ban on “normalising” surgery is not imminent, the intersex rights movement is already having an impact on medical attitudes and surgical decisions: a growing number of British parents are beginning to choose for their children not to have any surgery.

Tanya Dart’s daughter Clara, now five, has CAIS, the same condition as Dawn Vago. Doctors in the hospital where Tanya gave birth noticed something looked different as soon as she was born. “I’d never had a baby before, I just thought that’s what newborn babies looked like,” Tanya smiles. She is sitting in the living room of her London home, speaking to me over Skype in the brief window while she has a break from Clara and her seven-month-old brother. The doctors told Tanya she had a baby girl, but wrote in her notes that Clara was “ambiguous”.

Like Ruth, Tanya was told about her daughter’s condition behind a curtain on the maternity ward. “It was about 9pm and my husband had gone home. The registrar put his hands on his hips and started whispering, ‘You know, these could be testes. I hope you understand – this could be a boy.’” She shakes her head in disbelief. “It was like he was sharing a piece of gossip. I kept looking at my baby thinking, this can’t be. I hadn’t heard of intersex or DSD. If I’d heard anything about it, I’d have been more prepared.”

The Darts were referred to Great Ormond Street Hospital, where they met a psychologist and an endocrinologist. “They explained it so well. They made everything clear and they were compassionate, so I didn’t even think about surgery. The option was there, but the way they were explaining to us, it was quite clear that we could leave it. It made the choice easy.”

They know great challenges lie ahead for Clara. They haven’t decided how and when they are going to tell her. “We are following advice from the hospital that it has to be a very gradual process, starting from when we think is best,” Tanya says. They know that Clara will never be able to get pregnant, and have explained to her that some women can’t have babies of their own and can choose to adopt if they want to. Clara thinks that sounds like a very kind thing to do.

But their greatest worry is about how Clara might be perceived in a world that is unforgiving of difference. “Why is there stigma attached? In terms of being able to talk to others, and not be petrified about what people will think of us. I feel that everyone would take their children away from my child and say, ‘Don’t play with her’ if they knew.” Tanya pauses. “I want as many people as possible to know about these conditions. I want it to be the kind of thing that people can talk about. I hope there will be a day in my daughter’s lifetime where everyone knows about intersex, and it’s no big deal.”

• Some names have been changed.