When Shi entered the birth ward she, like 74 per cent of all women who give birth in a public hospital, expected she would be well warned about any risks posed to her associated with both vaginal and caesarean delivery. What happened, she said, was so life-changing she prefers to discuss it with emotional support at hand.

After a 48-hour labour which was not progressing, Shi was told she would be having a caesarean section. Believing this to be the case, Shi was entirely unprepared for what turned out to be a last-minute change to a forceps vaginal delivery.

The consent forms she signed only warned her about material risks associated with a C-section, and not instrumental delivery.

"The pain I suffered as a result is rare," Shi says. "I was never told they would use forceps; the doctor made the decision for me."

While she has since settled a legal claim, the cost to her physical and mental health has been so great that Shi says she is scared to have another child.

"They didn't respect me as a mum, as a woman. It's very hard to believe this would happen in an Australian hospital."

The birth of her daughter left her with third-degree anal sphincter injury, postpartum infection, shock, acute stress, anger, depression and ongoing pain.

"I lost months with my baby - and I can't have those days back," she said. "I should have been taking her out to the park, enjoying my time with her. Instead, I was in bed for four months recovering from injuries no doctor or nurse ever warned me about."

Shi is not alone. Birth trauma - and in particular, trauma linked to a lack of information about the risks of all forms of birth, not just caesarean - is leaving many women feeling helplessness and a lack of control when it comes to their own bodies.

The right of a woman to choose the method via which she gives birth is an increasingly contentious topic, as women, experts and even the two healthcare systems - private and public - remain divided on best practice.

"Childbirth has, until very recently, been regarded as a natural phenomenon and not a medical intervention," says Professor Andrew Korda, a senior urogynaecologist, gynaecological surgeon and professor of Obstetrics and Gynaecology at the University of Western Sydney.

"Years ago, you would not even contemplate asking a patient to give consent for a natural birth."

Korda is often called as an expert in birth trauma legal matters. He sees "one to two potential legal cases a week related to traumas associated with vaginal birth", compared to three years ago, when he would only see "one to two cases a year".

In the wake of significant court cases here and overseas, law firms are reporting a steady increase in the number of women starting proceedings against hospitals and doctors over lack of information, following injuries sustained during vaginal births.

Read more: Birth highs and lows outlined in NSW report on Mothers and Babies

Naty Guerrero-Diaz, principal lawyer at Slater and Gordon, says the firm currently has "more than a dozen birthing injury matters under investigation".

"This is a marked increase from even a few years ago. I believe this is indicative of women questioning the traditional thinking around deliveries and no longer being prepared to silently accept the injuries they have sustained," says Guerrero-Diaz, a medical negligence specialist.

"With vaginal births, there's a wide range of outcomes that are considered acceptable in the circumstances," she adds.

Bree Knoester, a partner at Adviceline Injury Lawyers, has also seen "inquiries with injuries of this type double over the past five years".

"Nearly all clients present with some form of risk factor - be it baby size, pre-labour swelling or maternal weight - however a vaginal birth is still actively encouraged," she says.

In 2010, the NSW government introduced its Towards Normal Birth policy, developed in response to concerns about rapidly increasing caesarean section rates in the state, which rose from 17.6 per cent in 1996 to 30.5 per cent in 2010. The policy, which is under review, aims to reduce non-medically-indicated intervention.

"A caesarean section operation is a surgical procedure, and as such will present an increased risk of complications such as haemorrhage, blood clots in the legs or lungs, and infection," a NSW Health spokeswoman said.

"In the case of a healthy woman who is expected to have an uncomplicated birth, intervention should be minimised, as every intervention carries a potential risk."

Another ambiguous area is forceps delivery, which Korda says is still not considered an intervention by many doctors.

"A forceps delivery, an intervention whichever way you look at, virtually doubles the risk of injuries associated with a normal vaginal delivery, such as urinary and fecal incontinence and a prolapse," he says.

Perineal tears (which separate the vagina from the anus) are also on the rise, with a recent report by the Australian Commission on Safety and Quality in Health Care finding "the Australian rate of third and fourth-degree perineal tears is above the reported average for comparable countries in the OECD".

"This is a truly difficult issue," says Dr Bernadette White, an obstetrician with two decades' experience and a spokeswoman for the Royal Australian and New Zealand College of Obstetricians and Gynecologists (RANZCOG).

"Thirty to 40 years ago, having a caesarean birth was considered an emergency procedure - it was a very big deal to have one."

In the interim, not only have C-sections become much safer but our lives look different. Most people lead largely sedentary lives and sugary and processed foods have come to dominate many people's diets.

As a result, obesity is increasing and is having a major impact on pregnancy. According to the Australian Institute of Health and Welfare, one-fifth of women who gave birth in 2016 were classified as obese, and a quarter were overweight.

Obesity in pregnancy contributes to increased risks of illness and death for both mother and baby, leading to an increased risk of thromboembolism, gestational diabetes, pre-eclampsia, post-partum haemorrhage and wound infections. Women who are obese while pregnant are also more likely to deliver via caesarean.

The average age at which women are having children has increased at over 30 for the first birth, and the number of children (1.74 babies) also matters.

For Professor Hans Peter Dietz, an obstetrician and gynaecologist from Sydney Medical School, the medical system's preoccupation with a "natural birth ideology" is not reflective of the reality of most women's experiences today.

"Women are getting older when they have their first baby, and getting bigger - it's amazing that our outcomes are still so good," he says.

"And there are major problems associated with this that people just aren't aware of, such as the older you get, the stiffer your tissues become, and therefore it's harder to stretch the birth canal to let the baby out.

"The older you are, the longer the pregnancy lasts, which means the baby is likely to get bigger, which means more trouble getting it out," he says. "The delay in childbirth has a major cost."

Ivana Alexander has been involved in a lawsuit following the birth of her only child.

At the time she was 30, had gestational diabetes and knew her baby was big, so she says she asked if she could have a caesarean.

She was told she should have a vaginal birth instead. As a doctor pulled out her 4-kilogram son with a vacuum device, Alexander says she felt him rip through her perineum (the skin between her vagina and anus).

"I felt like I was dying," she said.

Five years later, Alexander is doubly incontinent, has difficulties with sex and is still seeking help to repair skin that was torn apart. She is about to have her third reconstructive surgery.

And while she doesn't want to speak about the intricacies of her lawsuit, she says it's important women know about the consequences of vaginal births.

"People don't want to talk about this; it's such a sensitive area," she says. "But if no one says anything, then nothing will change and shake up the hospital system to make them realise how terrible the quality of life is for these women."

The RANZCOG's White says obstetricians are increasingly attending workshops to discuss the issue of consent and a woman's autonomy around birthing methods: "I have worked both in the private and public sectors, and I'm very aware of how important aspects of birth are to some women."

She says the pendulum swings both ways: while some women will insist on a C-section, others are adamant they want no intervention, even if it is recommended by doctors.

What it comes down to is respecting the woman's autonomy - even if it goes against the doctor's professional advice.

"If a woman has the capacity to provide informed consent, you have to accept that as a doctor," she says. "And if you can't, you have to step away."

The biggest issue for doctors is gauging whether to bring up the risks associated with vaginal birth if the woman presents as healthy and with no complications.

"We know it's about giving people information and not imposing on women what you think they should do," says White. "But when do you know how much you have to tell women before you unnecessarily frighten them?

Dr Stefan Hansson from Lund University in Sweden has similar concerns. After writing an article on this issue for The Conversation - where he concluded it was neither "ethical nor advisable to let the patient prioritise between different delivery outcomes ... but be instead informed of all the risks, at all life stages and for both mother and child" - he was surprised by the reaction in Australia.

"People thought I was a male chauvinist, that I was an old, traditional male doctor telling my patients what's best for them," he said.

"This wasn't at all my intention when I wrote it. I was saying that here in Sweden, doctors don't think it's right to leave the entire decision to the woman, not because she is not capable but because we are not sure they can take into account the additional risks posed by C-sections to subsequent pregnancies."

Unlike Australia, where women can elect to have a C-section in some private hospitals, Sweden has only the public system, which mandates that undertaking major surgery is a medical decision.

Hansson said a private health system that allows elective C-sections can be abused by doctors influenced by commercial reasons over that of the patient's welfare.

"A doctor performing a caesarean will charge three to four times as much as one performing a vaginal delivery," he said. "There are also severe consequences of a caesarean birth - the rupture of the uterus, for example, and the potential of the placenta growing into the scar tissue or even invading neighbouring organs, which can lead to horrific bleeding."

A recent review comparing C-section deliveries to vaginal births concluded that while caesarean deliveries have reduced rates of urinary incontinence and pelvic organ prolapse, they also have adverse associations, including with fertility, future pregnancy outcome and future pregnancy complications.

Other studies have found that women are three times more likely to die during caesarean deliverythan a vaginal birth, due mostly to blood clots, infections and complications from anaesthesia; and that women who have had a C-section are less likely to begin early breastfeeding than women who had a vaginal birth.

So what is the answer, legally and morally? "We may have to get women to sign a consent form before they have a vaginal birth to understand what a natural birth is, and the issues surrounding it," says White. "At the moment, a woman giving birth only has to sign a consent form when she's having a C-section."

Another issue is that much of the care is provided by midwives, who only deal with vaginal births and are not legally allowed to provide informed consent regarding C-section or instrumental deliveries.

"In Australia today, at a time when our population is becoming less and less healthy overall, there is less and less input from doctors in obstetrics as compared to midwives," says Dietz.

"If you don't see a doctor, there is no way legally you can be warned about all the risks associated with different delivery methods."

The Sydney Morning Herald