In a flat in north-east London, Abi is cradling her best friend’s baby. At 15 weeks old, the little boy is smiling up at her, testing out his first sounds. His mother, Rachel, prepares his bottle while Abi rocks him, showing all the love she would to any of her friends’ children. The only difference is that Abi gave birth to him.

Abi and Rachel, both 35, met on their first day at university in Birmingham in 2003 and rarely left one another’s side. At 16, Rachel had been diagnosed with MRKH, a congenital condition meaning her uterus was undeveloped. Although she produced eggs, she would never be able to carry children, something she kept to herself. “I’d tell people I didn’t want kids but deep down I was insanely jealous,” says Rachel, who works as an events producer in London. “I wanted them so badly but assumed I’d never have my own, so I learned to live with it.”

After meeting her boyfriend, Sam, at a warehouse party on the eve of 2014, she avoided the “family” chat for two years before confiding in him. “We continued our relationship knowing kids may or may not happen,” she says.

A weekend stay at Abi’s home, in November 2017, bringing together five friends, their partners and kids, presented an opportunity to open up to them, too. Abi, a mother to three boys, remembers: “My partner, Rich, was cooking a curry, the kids were asleep and we were sitting around the kitchen table. Everyone spilled something personal. When Rachel told us about her condition, I knew, in my gut, that I would help her to have a child.”

Rachel and Sam had explored IVF, surrogacy and adoption, but had dismissed using agencies, which can be vastly oversubscribed, with waits of up to two years to find a match. “It felt too impersonal; too life-changing somehow,” she says. Her younger sister had yet to start her own family; had she already had children, Rachel might have asked her to be a surrogate.

Abi and Rich, meanwhile, “spent Christmas contemplating what being a surrogate would mean for everyone. We had been so lucky, yet one of the people I love most hadn’t,” she says. “I hate this phrase but it was a no-brainer.”

She called Rachel in the new year and told her to sit down before offering to carry her baby. Rachel remembers: “She said it would be like ‘babysitting’ our embryo and that term stuck. She’d made up her mind, and that blew me away. I hadn’t told my friends expecting one of them to be the answer. When Abi offered, it felt, for the first time, as if having a child was a very real possibility.”

***

In the UK, the number of children born by surrogate is up to 10 times higher than it was a decade ago, according to the Law Commission, which recently consulted on modernising the process to better support parents, surrogate and child. While US states such as California have commercialised the arrangement, with surrogates earning well in excess of $50,000 (£38,300), it is illegal to pay someone for acting as a surrogate in the UK, meaning the process relies on the altruism of strangers recruited through an agency, or loved ones. It is not routinely available on the NHS, and the private medical costs are typically up to £16,000. “Known” surrogacy – between friends or relatives – is still rare: at Care, the UK’s largest private fertility group, they accounted for 10% of more than 100 surrogacy cycles at their clinics last year.

Surrogacy is a delicate arrangement with high stakes. Pregnancy and childbirth can be gruelling, and present health risks, while the unknown territory of handing over a baby you have carried – or parenting the child you have not – presents added fears over bonding or changes of heart, albeit rare.

When there is an existing friendship at the arrangement’s heart, the stakes can feel higher still, for both the surrogate carrying a longed-for child and parents asking such as sacrifice of someone they care for, typically with a family themselves to consider. (Medics and lawyers advise against surrogacy until women have completed their own families, citing concerns about reproductive health and fears that it would be harder for them to give up the baby.) Not surprisingly, the friendships that underpin these arrangements are life-changing.

Abi, Rachel and Sam embarked on medical appointments at a London fertility clinic. The friends were invited for counselling and asked to consider everything from how they would feel if Abi backed out, to how she would feel if she gave birth to a girl, after three sons. They set up a WhatsApp group. “We left Rich off that,” Abi says. “I’ll talk about body parts and womb washing till the cows come home but he saw his role as keeping things normal – remaining practical and pragmatic in a hyper-emotional situation.” They told their families, including Abi’s boys – four, three and nine months at the time. “We always talked about ‘Rachel and Sam’s baby’. We said, ‘Rachel’s womb doesn’t work but Mummy’s does, so we’re going to look after a baby for them.’”

In hindsight, living miles apart was good. If we were round the corner I’d have been posting steak through her letterbox

After initially being refused any NHS fertility treatment that would lead to surrogacy, Rachel successfully lobbied her local commissioning group for a single round of IVF, in May 2018, allowing her eggs to be extracted for fertilisation by Sam’s sperm, creating a viable embryo. It would later be placed in Abi’s uterus at a private clinic, using money Rachel’s parents had saved for her wedding. “Surrogacy is still seen as something you do if you’ve got money rather than through biological need,” Rachel says.

Abi was given oestrogen and progesterone, and the embryo was transferred, via catheter, in a simple, minutes-long procedure, on 2 October. “From that moment, it was out of my control,” Rachel says. “I felt like I was holding my breath.”

When Abi took a pregnancy test, at 7am on a Saturday morning nearly a fortnight later, Rachel and Sam were in bed, on the end of the phone. “When she sent through a picture of the positive test, we were in total shock; it was extremely emotional. We didn’t know how to get on with our day other than staring at that picture.” They remained in daily contact and Rachel travelled the 150 miles to Abi’s home for midwife appointments and scans, as well as attending antenatal classes, along with Rich. “In hindsight, the distance was a good thing,” Rachel says. “If we were round the corner, I’d have been posting steak through her letterbox.”

They had to consider how to announce the pregnancy. Rachel would say: “We’re expecting a baby, but I’m not pregnant. My friend is carrying our baby.” Abi, who works in public engagement at the BBC, recalls: “Everyone’s mouths dropped at work. My mum asked, ‘Why you?’ But they all thought it was amazing.”

When it came to maternity leave, Abi was entitled to a year, but took six weeks, while Rachel was entitled to a year’s adoption leave. Outdated surrogacy laws require that Abi’s name is on the birth certificate alongside Sam’s; had Abi and Rich been married, he would have been named as the father. They also recognise Abi as the mother until Rachel obtains the court order granting her legal parental status. Seven months on, she is still waiting. “The fact that on paper he’s still not my son is upsetting,” she says, “but I can’t dwell on it. It’s a process, so we treat it that way.”

Many surrogacy pairings put an agreement in place. Although not legally binding – it is illegal for solicitors to negotiate one – it helps mitigate against concerns over all aspects of the pregnancy, from supplements to who first holds the baby. Rachel and Abi decided against it. “If Abi had changed her mind on anything, we all would have,” Rachel says.

Surrogates can receive reasonable expenses, such as extra food, travel, childcare or housekeeping costs, and Rachel and Sam gave Abi a cash card. “It’s the trickiest part because no expenses can repay her,” Rachel says. “She was militant about not asking for too much, but I wanted her to have a meal on us because she had our son with her.”

The baby was born on 8 June 2019. Rachel and Sam drove Abi to the hospital and witnessed the birth. “I could hardly believe it was real,” says Rachel, who fainted as he was delivered into her arms. The couple spent the first two nights after his birth in hospital, down the corridor from Abi.

“Rich was working late and arrived to find us all in the room together and the baby just minutes old,” Abi says. “He stayed for the placenta delivery, had some tea and toast and went home to be there for our boys in the morning. I don’t think the scale of what we’ve done will hit us for a long time. I’m relieved at how normal it feels when I see the baby. Rachel was so generous with her trust in me.”

Rachel adds: “Abi put herself mentally and physically through the most selfless act for me, to make us a family. She gave up a huge part of her life during those months to change ours for ever. I couldn’t handle what I was putting her through at times but she’d always say: ‘You’re not putting me through this, I’ve chosen to do it.’ If I ever asked why, she would say: ‘Well, I can’t think why not.’”

***

As fertility medicine has advanced and different family units evolved, surrogacy has emerged as a more familiar route to parenthood, but demand far outweighs the number of women willing or able to volunteer, and the British legal system is playing catchup. London-based family lawyer Joanna Kay, who has advised on surrogacy for more than a decade, says: “The landscape of what a family looks like has changed beyond recognition, but the laws are from the mid-80s. Without a court order, intended parents can’t make decisions about their child’s medical care or education; there can be problems with passports and inheritance. I don’t think anyone would argue against the need for reform.

“In most cases, everyone knows what they’re signing up for and is happy to honour their agreement. On rare occasions things go wrong and the courts are asked to intervene. There have been a handful of cases where the surrogate didn’t want to hand over the baby or the intended parent didn’t want it.”

Other relationships between parents and surrogates have been deep and enduring. Kim Cotton, who became Britain’s first surrogate in 1985, went on to help her friend Linda, who was unable to carry children because of complications associated with a miscarriage; Cotton gave birth to twins in 1991. “The family moved to New Zealand when the twins were teenagers but I still track their lives, mostly through Facebook now,” says Cotton, who is 63, and the founder of the Cots surrogacy agency. “Christmases and birthdays are still special and the twins and I always send messages to mark them. My friendship with Linda remains the kind where you are for ever aware of that person and can pick up with them anytime, even if you don’t speak often.”

***

Yet even longed-for pregnancies don’t always run smoothly. After Laura was made infertile five years ago, at 28, by treatment for stage two cervical cancer, her best friend Kerrie represented her only hope of becoming a biological mother. Last year, Kerrie offered to carry Laura’s fertilised eggs, frozen before she began intensive chemo and radiotherapy five years ago.

They had been friends since childhood and shared everything, Laura says, over a cup of tea at Kerrie’s home in Lancashire. “Relationships, breakups, marriages, my illness; she cries with me and laughs with me,” she says.

In 2014, Laura, a nursery manager, and her now-husband Grant were about to start IVF for problems unconnected to her own fertility when a routine smear test detected cancerous cells. “They talked about a hysterectomy,” she remembers. “Knowing my illness would take away my chance of having children was what broke me, not the cancer.” By this point in the story, both women are in tears. “As we left the hospital, I told Grant to leave me,” Laura adds. He didn’t. And while a hysterectomy was ruled out, Laura spent Christmas and New Year’s Eve undergoing treatment, with Kerrie by her side. She had delayed it by one month, so her eggs could be extracted and later used to try for a child via surrogate.

‘She gave me my only chance of being a biological mum,’ says Laura (left) of Kerrie. Photograph: Shaw & Shaw/The Guardian

In April 2015, a scan revealed the tumour had gone. When Grant and Laura married in Cyprus in 2016, Kerrie was a bridesmaid. “When I was ill, a few friends had offered to be a surrogate,” Laura says. “And when we finally came round to thinking about it, two years ago, it was Grant who said: ‘It has to be Kerrie.’”

Kerrie, 33 and a hairdresser, had a similar conversation with her husband, Danny. “At the clinic, he told us he knew when Laura became ill that I would do it one day. I’d had two good pregnancies and it would only be nine months of my life to improve hers for ever. I focused on seeing them with a child.”

Although it was NHS-funded IVF that had led to the discovery of Laura’s cancer, when surrogacy became her only option, the funding was withdrawn. “I didn’t let it go without a fight,” she says. “Ultimately they were taking it away because I had cancer. The NHS saved my life; to then dictate that life isn’t fair.”

In the end Laura’s family paid for her treatment. “They would have helped me with a house deposit but I said, no, give me a baby, please.” The surrogacy was delayed when Kerrie unexpectedly became pregnant with her third child in 2018, but in October 2019 Laura’s eggs were thawed. Eight had been fertilised – but only one looked viable for transfer and pregnancy. It was placed in Kerrie’s womb on 7 October. The women held hands as they sat on the clinic’s bed. “When they told us there was only one chance, I couldn’t look at Laura,” Kerrie says. “She can read my thoughts. I wanted to stay positive for her but the pressure was huge.”

I’d been carrying her most treasured possession. We were numb. We drove home in silence

On 23 October, two clear lines showed on the pregnancy stick, but Kerrie tested and retested, with Laura by her side, to be sure. Both women were ecstatic. However, on 1 November Kerrie started bleeding. A miscarriage, at five weeks, was confirmed two days later at hospital.

“It hit me like a ton of bricks,” Kerrie says. “I’d been carrying her most treasured possession. We were numb. We drove home in silence. My priority was being strong for her but I was broken. We went from speaking all day, every day, to nothing for 48 hours. I’d type a message asking, ‘Are you OK?’ then delete it. When we eventually sat down together, we cried our hearts out. I felt responsible but I knew I’d done everything I could.”

Laura is still coming to terms with her grief. “I was uncontrollable, heartbroken. We each had our own grieving to do; it wasn’t that we didn’t want to speak, we just didn’t have the words and didn’t want to add to each other’s pain.”

Kerrie has offered to be a surrogate again, with a donor egg, but Laura says she couldn’t put her friend through it. She has also thought about adoption but needs time to heal before giving it serious consideration.

“I don’t think anybody realises how difficult the process is,” she says. “Kerrie gave me my only chance of being a biological mum. I didn’t know I could love her any more than I already did.”

***

Despite the spike in surrogacies over the past decade – and a rise in profile following the examples of celebrities Kim Kardashian, Elton John, Sarah Jessica Parker and Tom Daley – just 302 (0.4%) of 75,425 fertility treatment cycles recorded by UK watchdog the Human Fertilisation & Embryology Authority (HFEA) in 2017 were surrogacies. But it has become a viable route for gay men who want to start a family. At Care, two-thirds of surrogacies in 2018/19 were for men in same-sex relationships, an option aided by the HFEA’s 2011 decision to offer £750 compensation to egg donors, triggering more women to help others on their parenthood journeys. This, says consultant gynaecologist David Polson, “opened up the options for same-sex couples to seek out a surrogate and become parents”. Advances in freezing fertilised eggs have also made it more likely that a thawed embryo will be suitable for transfer to another woman’s womb.

In Kent, Kevin, 45, a chief marketing officer, and Spencer, 30, a solicitor, are getting their six-month-old son ready for bed when the other half of “Sawyer’s birthing squad” (the name they gave their pregnancy WhatsApp group) arrives: surrogate Leanne, 36, and her sister Rachael, 33, Sawyer’s egg donor. “There’s not many teams like us out there,” says Leanne, grabbing a bedtime cuddle.

Spencer and Kevin have been together 10 years and married in 2015. “I told Kevin on our first date that I needed to be a dad,” Spencer says. “The biological connection was important to us. We wanted to be involved from the start.” They explored agencies but the networking aspect turned them off. “It was like speed dating. There were more couples than surrogates. It felt hard to be your true self.” They spoke to relatives and asked close friends but none provided an obvious solution. So, despite reservations, they turned to an agency and invested five months getting to know a potential surrogate, only to be let down by an early morning text weeks before treatment was due to start.

‘There’s not many teams like us out there’: Rachael (left), egg donor, and her sister Leanne (right), surrogate for Kevin (left) and Spencer. Photograph: Silvana Trevale/The Guardian

The one thing they did have was an egg donor. (Medics typically discourage having the same woman perform both functions, to offset concerns around the possibility of bonding too strongly with the baby.) Spencer and Rachael, a credit controller, had become friends two years earlier after meeting on an IVF forum on Facebook. Rachael, then pregnant with her third child, was exploring egg donation, and Spencer wanted to know more about surrogacy. They lived nearby and began meeting up, forming a close friendship that involved weekends together, takeaways, dinners and days out. Spencer and Kevin became unofficial uncles to Rachael’s youngest son and joined in family celebrations, which is how they grew close to Leanne, a mental health support worker who had three sons of her own.

Leanne remembers: “Kevin and Spencer were lovely, and I’d seen how close they all were and how badly the boys wanted to be parents. When Rachael told me their surrogate had let them down, I instinctively offered.”

The group drew up a 12-page “intention agreement”, detailing expenses, medical tests, pregnancy supplements and protection – including life and critical illness insurance – for Leanne’s children in the event that anything went wrong. Kevin and Spencer spent £25,000: £6,000 for the cost of Rachael’s egg donation; £6,500 on medical appointments, screening tests (for all four), medication and scans; £2,500 to transfer their embryo to Leanne’s womb; and £10,000 on surrogate expenses. On pregnancy test day, they sat around Leanne’s kitchen table together, dipping the stick in a cup she’d wee’d in.

“This was the next best thing to carrying the baby ourselves,” Spencer says. “We were so involved. Friendship-first gave us trust and openness.” The expectant dads attended scans, sent hampers each trimester – the first contained ginger biscuits and tea for morning sickness – and downloaded an app that allowed them to read bedtime stories for Leanne to play to her belly. When her waters broke three months early, at 28 weeks, the responsibility weighed heavily for all. Leanne says, “You don’t want to let anything go wrong. Decisions about what happened next were theirs to make. I felt guilty.” The men felt responsible, too. “Leanne has three children; she had to go home perfect at the end of this,” Spencer says.

Some nurses called Leanne ‘Mum’ which none of us wanted. It felt antiquated

Leanne was monitored as an outpatient until labour started a month later. When Sawyer arrived, at 2.36am on 6 April, eight weeks premature and weighing 5lb, all four were in the room, Rachael as birthing partner. Sawyer spent 16 days in neonatal intensive care. His fathers stayed by his side but the now familiar outdated legalities meant Leanne had to return for his discharge.

Even once they have left hospital, it is common for surrogates to be contacted by health professionals seeking consent for newborn checks, despite parents being present. Kevin remembers: “Before the birth, our consultant emailed ahead to enforce our right to be there. Some nurses called Leanne ‘Mum’ which none of us wanted. It felt antiquated. I think it’s sexuality and gender more than surrogacy. It took us being by his side for 16 days to prove ourselves, and it shouldn’t be that way.”

After the birth, Leanne was flooded with emotion: “Your body doesn’t know you’re a surrogate; he was premature and my natural instinct was to know he was all right. I talked a lot with Rachael to be sure what I was feeling was OK. The openness and honesty between me and the boys was vital. Once home, I was back to being Leanne again.”

She expressed and froze milk for Sawyer for two weeks before returning to work. Going home from hospital, Kevin and Spencer stopped at her house, “to give her boys the first cuddle,” Spencer says. “They’d been through a lot, too.”

When the friends share their story with others, it is the egg donation that tends to generate the most interest, Kevin says, but for Rachael it represented nothing more than a tiny piece of DNA. “It’s that black and white for me,” she says. “My own children are the ones I’ve created with my husband. The way Kevin and Spencer look at Sawyer is the exact reason I wanted to do this.”

They see each other often and last month shared a Christmas outing and an early New Year’s Eve celebration before Sawyer’s bedtime. “I want our son to know who the two most incredible women on the planet are,” Kevin says. “They’ll for ever have that bond with him. The more love he has, the better.”

Back in north-east London, Rachel and Abi echo the sentiment. As the baby goes down for his nap, the friends leaf through a photo book of their pregnancy, created for their children. “I can’t wait for my son to know how many people brought him into the world,” Rachel says. “It’s the biggest act of kindness imaginable; I can never thank her enough.”

Abi smiles. “But you don’t need to thank me,” she says, “because it just feels entirely normal. We were going to be friends for the rest of our lives anyway; it’s just cemented our bond.”

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