Holding a new baby for the first time is, for any parent, a very special moment. It was one for which Courtney Bryant and her partner, Daniel, had to wait five weeks.

Albie and Reuben, the couple’s twin boys, are two of the 60,000 babies – one in every 13 – born prematurely in the UK each year. When they were delivered on 6 August this year, 13 weeks too soon, they weighed only 750g (1lb 10oz) and 1.05kg (2lb 5oz) respectively. “They were smaller than my hand, so tiny, like little birds,” recalls Courtney. “They had to be rushed away. I barely saw them, let alone touched them.”

Their portraits were among those to feature in a recent photography exhibition developed with help from staff at Kingston University and St George’s, University of London that offered a window on to the lives of premature babies and their families on the neonatal unit at St George’s.

It is a totally unexpected world, says Courtney, completely at odds with the one new parents expect to enter. “There are so many machines, noises, alarms, lights. There are constant tests and numbers. There is even a particular smell. It is clinical, hot. Nothing about it seems natural. Yet that room was my babies’ world. It was what was keeping them alive.”

Courtney Bryant and Daniel Hall, parents of Albie, right, and Reuben and one of the images from the exhibition at St George’s, Tooting – one of the hospitals to which the twins were admitted. Photograph: Jan Podsiadly

Surrounded by the sickest infants, in a place where not all stories have a happy ending and those that do involve “trauma, anxiety and setbacks”, Courtney has now spent 17 weeks with her babies in special care (St George’s was the third of four hospitals to which she and the babies have been admitted).

Both babies are now doing well – the family is currently at Addenbrooke’s hospital in Cambridge. Albie is recovering from a bowel inflammation and should be ready to go home well in time for Christmas. Reuben, now weighing over 3.6kg – “a little fat thing, I feel like I am lifting a toddler” – has technically been discharged already.

Courtney, a 30-year-old care supervisor from Harlow in Essex, says the medical teams caring for her twins have all been amazing. “They are special people. They understand some of what you can only understand if you have been there.”

The exhibition’s aim, says Rosa María Mendizábal Espinosa, a researcher at Kingston University and St George’s joint faculty of health, social care and education, was to “raise awareness about the importance of making parents feel like parents in the neonatal unit”. The sense of powerlessness as the parent of a very sick baby can make this very hard, says Courtney. “You can’t even touch them at first because their skin is so fragile. There are tubes everywhere. For five weeks, Albie was too poorly to be held. All I could do was sit and talk to him. The nurses told me that really would help so I did it for 16 hours at a time.”

She saw parents for whom the stress was simply too much. “Some babies arrived and no one visited for weeks. It is heartbreaking but I can understand where that comes from. The human instinct is to protect yourself. You have someone so vulnerable, who you love so much, you don’t think they are going to survive and you couldn’t take the hurt of that so you separate yourself.”

Baby Alexander, pictured with his mother, Pauline in one of the images from the exhibition, was born on 22 July, at 23 weeks. He was discharged home at the end of October and is doing well. Photograph: Jan Podsiadly

About a third of cases where babies are born before 37 weeks – full term – are unexplained. Although Courtney’s identical-twin pregnancy was considered high-risk and she was found to have a short cervix (cervical weakness, multiple birth, infection and pre-eclampsia are the most common risk factors), it appeared to be progressing well and tests indicated the babies could be delivered by caesarean section at 36 weeks.

So when Courtney went to her local hospital with a bad back – a precaution insisted on by her mother – she was shocked to learn she was in established labour. Two neonatal intensive care incubators were located at St Peter’s hospital in Surrey and she was transferred by ambulance. Attempts to delay the labour were unsuccessful and doctors explained that her babies were coming and at risk of complications.

Breathing, feeding and keeping warm are often difficult for babies born early and they are vulnerable to infection and continuing developmental and health problems. “I was so naive. I thought everything was going to be fine. That none of it would happen to my babies,” says Courtney. “Albie has had everything on their list apart from heart problems.”

At the lowest point, Albie and Courtney were transferred to St George’s, leaving Reuben and Daniel in Surrey. “Albie had suddenly become really poorly and needed specialist surgery but it took four hours to get him stable enough to even do that,” says Courtney. “I was taken to the dreaded room which parents hate, where bad news is given. I was told the surgery was his only chance, but that it was a very slim one. I signed the consent.”

After several horrific hours, Albie emerged. His condition remained critical for two weeks. “He survived the surgery but I could never relax.” Good days could and frequently were followed by bad ones. “It can all seem brighter and then they just stop breathing and everyone runs in. These babies are dancing between life and death all the time.

“I never knew if I would take two babies home,” says Courtney. “I was on my own. My partner was in another hospital with Reuben. I was just looking at my tiny baby and hoping and praying he would survive. Every time an alarm goes there is the horrible but immense relief when it isn’t your baby.”

When Courtney was finally able to hold Albie – the first time with Reuben had been immediately before Albie’s transfer – the fear of causing pain was crippling. “I was so scared. It was such a special moment, ruined by anxiety.”

Now, with the babies stronger, Courtney finds her need to touch them overwhelming. “It is so important and prematurity takes it away. Now I do anything I can – the washing, nappy changes, feeds. I am their mum.”

The experience of prematurity means that that particular mum is not the one she expected to be. “I think I will always be more protective, more anxious. They remain at risk of infection and I will be worried about that. Right now I don’t want to share them with anyone.”

Courtney says she and her partner can now finally consider the future and focus on the positives. “We are seeing their personalities and their bond. When they are together they always reach out for each other, but they are very different,” she says. “Reuben is highly strung, he screams the place down when he wants something. Albie is more laid back.”

They will, she predicts, keep her very busy. “I can’t wait!”

• For information about prematurity, visit tommys.org