For some, pregnancy is a straightforward process with nothing to feel stressed about except what colour to paint the newborn’s bedroom. For others, it’s just not like that. Olivia Gordon miscarried her first pregnancy, and the first two trimesters of her second were dogged by complications and test results that indicated her baby might have a chromosomal abnormality.

But, at 29 weeks, she and her husband were feeling hopeful. Specialists had given the baby a clean bill of health and told them to enjoy the rest of the pregnancy. They dared to start making a list of things they would need, things like nappies and a breast pump.

Then Olivia noticed a strange “stitch-like” sensation. The couple took a bus to their local hospital in north London to get it checked. They assumed it would just be routine. It was not. A scan found she had excess amniotic fluid, and her baby had fluid around the lungs and under the scalp. “I’m afraid it’s not great news,” said the sonographer. The baby had a rare condition called hydrops fetalis, where the body’s lymphatic system fails. As Gordon found out, googling later at home, it had always meant inevitable death, sometimes in the womb, sometimes after a premature birth.

But Olivia Gordon was lucky enough to live in London, and to be pregnant at the right time. Three days later, she was at University College Hospital’s department of fetal medicine, meeting Professor Donald Peebles. The fluid was still there, threatening her baby, but he had a solution. By inserting a “shunt”, a plastic drainage tube, into the baby’s body while still in the womb, the fluid could be drained away. It was an unusual procedure, only carried out five times a year as hydrops was so rare. There was a one-in-three chance that the procedure would trigger premature birth, and it had to be done immediately.

In her new book. The First Breath, Gordon describes the moment that the professor plunges the cannula into her baby’s chest. “It was as if Peebles was playing a video game or taking a pot shot at a coconut. Brutally basic.”

Her son was born a few weeks later, a tiny scrap of life who spent months in neo-natal units. The whole experience was traumatic and gruelling, and many women would have wanted to leave it behind as fast as they could. Gordon, a freelance journalist with a huge interest in science, could not. She wanted to tell the story of foetal medicine’s everyday miracles “changing history in our lifetimes.” Joel, her son, would not have survived in previous decades.

As well as telling her own story, her book traces the history of surgery within the womb. She also talks to many other parents who had similar experiences. Some of their babies survived relatively unscathed, others have severe disabilities, others died. It’s a book full of emotion and one that medical practitioners should read.

Her own trauma had faded by the time she wrote the book, although she burst into tears the first time she went back to the neo-natal unit — “even the smell of the sanitiser brought back memories,” she says. It’s certainly not a book that one would hand to a pregnant woman.

She agrees, but says it’s important to remember that not all pregnancies go well or end happily — and hopes it will help the isolation that parents can feel when things go wrong.

In the book, she points to a long history of fascination with wombs and newborn babies. In 1897, for example, a Prussian Jewish immigrant Martin Couney, put premature babies in incubators on display at Earls Court. He later emigrated to America and did the same, becoming a popular attraction at Coney Island for 40 years. The 25 cents that the public paid for a ticket to see the babies funded doctors and nurses to care for them. Couney was condemned by many as a charlatan but the parents of the babies he saved thought him a miracle worker.

Today’s miracle workers are the doctors who build on early experiments on primates to constantly expand the range of what can be cured while the foetus is still developing. Inevitably, this means that babies can be saved at earlier stages of gestation than previously, a complicating factor at a time when women’s abortion rights are being fought over. Gordon believes that parents should have the final say in whether to intervene to save a child. “I would never judge anyone for making their decisions.”

Doctors, she says, can appear to be God-like, modern miracle workers, but often sound more certain than they are. “You assume as a patient that they know, but often they’re just guessing. You trust them, they have to make a decision. Resuscitating babies is a very grey area. We can save babies… what is the quality of life, and who decides?”

She comes from a secular Jewish family, and religion had never played much of a role in her life until those dark months when she feared her baby would die. “I don’t believe in God, but I prayed for half-hours at a time,” she writes.

One day she drove to Muswell Hill Synagogue, nominally her family’s shul but not somewhere she was familiar with. There was a small gathering inside, she knocked on the door and tearfully asked the rabbi if he would pray with her for her baby. “Of course,” he said, and they lit a candle and prayed together.

Later, baby Joel went to nursery at the shul, and Rabbi David Mason continued to give the family support.

Now Gordon and her husband live in Oxford, with Joel and daughter Anna, also born prematurely, but not with the health problems that have dogged Joel. The new frontiers of foetal medicine mean that often these babies are pioneers throughout their lives, as the first ones to survive previously fatal syndromes.

At eight, Gordon writes, Joel is “a wise, hilarious and zany little schoolboy, the shunt Peebles implanted still in his chest, causing no harm.”

The science of foetal medicine inspired Gordon’s book, but the experience of having Joel has also, she says, given her a new appreciation of religion. “When life is going well, you don’t need religion, we don’t need to think about life and death and God. When they are not, that’s when we turn to religion. “

‘The First Breath’ is published this week by Macmillan