At the age of 24, Shannon Headd decided she wanted to get her breasts enlarged.

She'd been patiently waiting for them to grow bigger since she was a teenager, so she could look more 'womanly', and was convinced she'd never be 'happy' or 'confident' without them.

But, as a part-time waitress and single mother living in a one-bedroom council flat with her two-year-old son, she assumed she could never afford the £5,000 cost of surgery.

Yet then, Shannon started noticing adverts for breast enlargements popping up when she watched her favourite TV shows online — Love Island, among others — where she enviously watched clips of confident-looking young women with identikit busts jumping into swimming pools or posing on boats in exotic locations.

And, far from being beyond the financial reach of an impoverished, single mother like her, the companies' marketing messages seemed to suggest that surgery might be affordable after all — thanks to loans with low or zero per cent interest rates. A few months on, Shannon has gone from an A-cup to 34DD breasts.

Adverts for breast enlargement surgery are leading to a disturbing trend where young women are taking out crippling loans for breast implants

Shannon Headd, from Hackney, east London, took out a £6,339.10 loan to cover a £5,000 which saw her go from an A-cup to 34DD. The 24-year-old single mother will be paying back the loan at a rate of £160 a month for the next three years

According to paperwork seen by the Mail, she's also saddled with a £6,339.10 loan for the £5,000 operation, which she'll be paying back at the rate of £160 a month over the next three years, out of her meagre earnings and child benefits.

Shannon, from Hackney, East London, went for a free consultation with cosmetic surgery chain MYA at the London Fitzroy Clinic. She says: 'The patient co-ordinator first asked me why I wanted it done. Her next question was how I was going to pay for it.

'I'd said I'd seen they were offering finance, so she got on the computer to help with the loan application.

'At first, I got declined. So she asked me if there was any other money I could use. I said I got benefits for my son. So she said: 'Try that.'

'I was surprised because I didn't know that counted as income.

'I put in the new amount and, this time, I got accepted by their loan company. Only the APR rate had doubled from the 9.9 per cent I'd seen on their website to nearly 20 per cent.

'I asked the adviser why there was such a jump and she said the percentage I'd seen was actually just an average.

'I did think it was a lot, but I wanted the surgery so much, and my son never goes without, so I signed up on the spot.'

Today, Shannon couldn't be happier. The long-term 'what ifs' of being trapped in debt, while in such precarious financial straits, do not worry her.

And it would appear that there are thousands more like her: around 9,000 women opted for breast augmentations this year, with a growing number only able to do so after signing up for loans, promoted by the cosmetic surgery companies using partner finance firms.

The practice is similar to car finance loans, some of which have been accused of getting people into debt by selling them flashy cars they can ill afford.

There are thought to be up to ten cosmetic surgery firms in the UK, including market leaders The Harley Medical Group, MYA and Transform, offering financial agreements via loan partners.

Nurse Laurane, 25, is in debt after signing up to a loan so that she could afford to have breast augmentation surgery

Nurse Laurane Galand, 25, signed up to pay £6,466.08 for her surgery. She insists the debt is worth it, and that if she had known about the loans when she was younger she would have done it earlier

There is also a growing number of finance companies specifically offering to lend money for cosmetic surgery.

Often, loans are arranged with the guidance of patient advisers who, the Mail discovered, receive commission for every patient they sign up for surgery.

More worrying still, many now advertise their services on TV and online, seemingly targeting shows watched by young women — those who are most likely to want surgery and least likely to be able to afford it.

The growth of the cosmetic surgery advertising and its links to the loan industry throws up a number of difficult questions.

Chief among them is why, in a nation where it's illegal to sell prescription-only drugs, is it legal to advertise enhancement surgery to healthy young women?

Why is cosmetic surgery the only form of medicine, which is usually not medically needed, where companies advertise loans at the same time as advertising their services?

And why is surgery often being sold as a flippant lifestyle choice when not only is the surgery itself not without risk, but the consequences of defaulting on a loan can be so serious?

Nurse Laurane Galand is another young woman who is now in debt after signing up for a loan for breast implants.

Like Shannon, she'd noticed more boob job adverts on TV. She also believed the message that the cosmetic surgery she'd always longed for, to enhance her 34A breasts, was now within her reach.

Laurane, 25, from Westcliff-on-Sea, Essex, said: 'I'm on a part-time nurse's salary and use finance deals for my car and phone, so I never thought I'd be able to afford it.

'But then I saw zero per cent finance deals advertised on the website.' Encouraged, Laurane went for a consultation with the cosmetic surgery company Transform. When she keyed in her £24,000 earnings, she was also initially turned down by the firm's recommended lender.

Undeterred, she simply went out into the waiting area, where she signed up for a deal with another finance company on her phone at an APR of 14.1 per cent.

'I've signed up to pay £6,466.08 for the £4,999 I thought I'd be paying,' she says.

TV adverts for cosmetic surgery including breast implants regularly pop up on screens now

Shannon had to use her child benefits to get her loan application approved - but the APR jumped from 9.9 per cent to nearly 20

Laurane, who lives with her fiance James at his parents' home while they're saving up to get married, insists the debt is worth it. She is delighted with her D-cups — even if her new figure means she will have to work extra shifts.

'The other day, I tried on a 36DD bra and it was too small. I'd never been so happy.

'If I'd known about loans when I was younger, I'd have had one sooner.'

Even very young girls are being accepted for finance. Louise Wilson got a loan for breast enhancement surgery this year at 19.

The cost of going from an A-cup to a D has been a £5,898 loan, with an APR rate of 19.9 per cent, which Louise will pay off in £224 monthly instalments over two years, a decision she says she made because of her 'lack of body confidence'.

However, she explains she's able to afford it on her salary because she still lives at home with her mother who, Louise admits, was less than thrilled about her daughter's decision.

Louise, who works as a nursery practitioner, says: 'Initially, I went to my bank for a loan, but I was declined because I didn't have enough credit history.

'Then I saw that MYA, the company I wanted to go to for the operation, had its own finance. That seemed like the answer.' Following her consultation in April, Louise was talked through the finance process, though she admits she 'honestly [doesn't] understand APRs'.

'Once I had the application up on-screen, I knew within seconds I'd been accepted. It took me less than three minutes.'

Joanne Jones, 24, is a health care support worker from Huddersfield with a degree in psychology. She has a student loan to pay off as soon as her income hits £25,000 and a new home to renovate.

Even so, Joanne felt that an operation to take her from an A to a D-cup was a priority.

When she went for her initial consultation with MYA, Joanne says her patient co-ordinator suggested she find the remaining cash by asking her bank for a zero per cent credit card to pay it over two years. To pay off the £3,500 debt, she will soon have to increase her payments to about £200 a month.

Professor David Veale, a consultant psychiatrist at The Priory Hospital in North London and an expert in body dysmorphic disorder, says: 'I can't think of any other private medical care that offers loans at the same time as offering its services.

'When a patient wants surgery, often the only thing stopping them is the cost.

'The companies are clever because they have identified money as being the main barrier.

Joanne Jones, 24, claims her patient co-ordinator suggested she find the remaining cash for her surgery by asking her bank for a zero per cent credit card to pay it over two years. Her payments will soon hit £200 a month

'By offering loans, they are reducing that barrier and facilitating the process.'

TV adverts for breast enlargements may also increase body dissatisfaction in the first place, adds Professor Veale.

'We live in a society where people increasingly define themselves by appearance. If you're already feeling insecure, the advertising feeds that insecurity and you feel you need to do something about it.'

Indeed, cosmetic surgery companies have increasingly come under fire for their commercials. In January last year, an ad for cosmetic surgery chain MYA showed two women in a changing room, in which one complained her breasts were saggy after losing weight, but are now 'full and perky again'.

Another tells a friend that she couldn't go shopping for clothes before her surgery because 'my breasts were out of proportion'.

The Advertising Standards Authority (ASA) upheld a complaint against the advert, saying it was 'concerned that the ad might encourage viewers, particularly young women and teenage girls, to think about and dwell on their own insecurities with their bodies'.

Yet, this year, the company was again censured — this time, by mental health campaigners, after running more ads on the ITV Hub streaming service (which shows Love Island), offering loans with a 9.9 per cent interest rate through third-party lenders for cosmetic surgery costing up to £10,000.

The Daily Mail asked MYA to respond to concerns about the young women being helped to take out loans.

A spokesperson said: 'Not everyone can have cosmetic surgery with MYA.

'We carry out a range of health and suitability checks and we do not operate on anyone under the age of 18.'

MYA says its loan providers are regulated by the Financial Conduct Authority and carry out affordability checks, so that only 23 per cent of applicants get approved.

It added: 'Should a life- changing procedure only be available to the rich and famous? Why shouldn't a medically and psychologically suitable patient be able to gain assistance to finance their procedure?

'If anyone doesn't have the funds for surgery in their bank account, then they may require support as to what other options are available.' Transform, another cosmetic surgery finance provider, says that loans are offered only after clients have been subjected to affordability and credit rating checks.

However, it confirmed there is an underlying incentive for patient co-ordinators.

MYA says its loan providers are regulated by the Financial Conduct Authority and carry out affordability checks, so that only 23 per cent of applicants get approved

Transform told the Mail in a statement: 'Our patient advisors, and the surgeons we work with, work independently of one another. Before any procedure, prospective patients will participate in a comprehensive surgical consultation process, where their surgeon will discuss the risks, benefits and limitations of surgery, with no obligation for the patient to proceed.

'A patient's journey is therefore determined by their surgeon and is based on an impartial clinical assessment specific to their individual circumstances.

'Therefore, while patient advisors do receive a performance-related remuneration payment if a patient is ultimately admitted by their surgeon, this process is entirely independent of the surgical consultation, patient education and consent process.'

MYA did not respond when asked if its patient co-ordinators are paid on commission.

Lawyer Michael Saul is a partner at the cosmetic law firm TJL Solicitors. He sees ethical problems with the growing number of commercials for cosmetic surgery services — as well as their partnerships with loan companies.

Mr Saul says: 'There's nothing legally to stop a clinic providing the finance to enable a patient to afford it.

'But it's questionable ethically, as well as being a concerning sign of the times.'

While there are plenty of reputable plastic surgeons out there, some businesses become 'conveyor belts'.

He's also seeing a spreading normalisation of what is, essentially, major surgery, which is never without risk.

'There are always the normal surgical risks — infection associated with anaesthetic and bad scarring,' he adds.

'Then there are also issues peculiar to breast augmentation, such as capsular contracture, where you get a capsule of scar tissue forming around the implant. This can lead to distortion, pain and asymmetry and hardness in the breast.'

One study by the Journal Of Plastic, Reconstructive and Aesthetic Surgery in 2013 found a quarter of breast augmentation patients required revision or correction more than once.

According to official NHS advice, most breast implants will need to be replaced within ten years. Yet there is no mention of this in the adverts.

Mark Wilson, of the ASA, says complaints about the way in which cosmetic surgery firms advertise are being 'assessed', adding that adverts shown during Love Island 'are on our radar'.

Finance expert James Herbert, CEO of Hastee Pay, says young people are not receiving the financial education to understand what they are getting themselves into.

And body image expert Chris Calland, who goes into schools to talk to young girls, believes we are heading towards a tipping point where breast implants are seen as 'a rite of passage' for smaller-chested girls.

Chris, co-author of the book Body Image In The Primary School, says: 'In schools, we often meet children who haven't yet gone through puberty, but who are already talking about changing their body shape.

'Cosmetic surgery is often talked about as if it's a 'quick fix' — like a trip to the hairdresser's.

'These companies are preying on young girls' insecurities, with no sense of responsibility for their long-term impact — both physical and financial — which can last a lifetime.'

Some names in this article have been changed. Tanith Carey is author of Girls, Uninterrupted: Steps For Building Stronger Girls In A Challenging World (Icon, £7.99).