Fertility treatments are a booming business but are Kiwis getting a fair deal?

With more people seeking help to fall pregnant, the business of babies is booming but experts are concerned potential parents are paying thousands for extras that aren't evidence-based.

At eight-months, Ihaka is one loved-on baby but he's got something that makes him extra extraordinary - he got a jump-start in a petri dish.

"It's part of his whakapapa now - the long winding road and the labs of Fertility Associates at St George's hospital. That's where he's from now," mum Tania Herbert told Newshub Nation.

"You don't know what love at first sight is until you meet your kids. We are so blessed."

For Tania and partner Ryan, it's been a journey. They really wanted a baby but when it wasn't happening, discovered Tania needed surgery to remove a blocked fallopian tube. 

They would need help to fall pregnant - in vitro fertilization - IVF.  

To qualify for public funding, women must have a body mass index or BMI of less than 32. So Tania went on a weight-loss programme. She lost 25 kilos only to discover how long she'd be waiting on the hospital list - between 18 months and 2 years.  

With time ticking, Tania's family offered to pay around $16,000 dollars for a private round of IVF - which took her some getting used to. 

"I'd say, ‘what if it doesn't work?  I'm gonna have that burden to carry.’ I didn't want that."

It's financial stress familiar to many of those who go for IVF. In this case, it's a happy ending. 

"I ran into the kitchen and got the pregnancy test and threw it in [Ryan’s] face, and he didn't know what was happening, and there were tears and screams and so much happiness," Tania said. 

But depending on age at least half the time, it isn't so successful. 

Since Louise Brown became the world's first test-tube baby in 1978, more than 8 million IVF children have been born. In New Zealand, the biggest fertility business, Fertility Associates, is seeking $100 million from private equity companies to expand.

Basic IVF usually costs well over $10,000. And there are optional extras at premium prices. 

There's preimplantation genetic screening for $1260 per embryo. Time lapse morphology for $1000, oocyte activation for $380. 

University of Auckland’s Professor Cindy Farquhar's research has found 80 percent of Australasian clinics are offering add-on services, and that none of them are backed by high-quality evidence showing they improve chances of a live birth. 

“It is a business, and I think that's grown out of the fact that few countries in the world fund it. It's a successful business, there's no doubt about it,” she told Newshub Nation. 

"There's insufficient evidence really to recommend [add-ons] and especially to ask people to pay for them."

She says the only add-on with reasonable evidence is called 'embryoglue' - but what about the rest? 

"My advice for patients is, 'Hey, maybe we don't have the evidence for this and that you're better to save your money for something that we do know is worthwhile, and in many cases, that will be having a second cycle of treatment,'" she said. 

Fertility Associates Wellington Medical Director Andrew Murray told Newshub Nation the problem is a lack of big trials showing the efficacy of add-ons.

"To show a small difference in effect you need a huge large study that might take many years to complete, and that's just time our patients simply don't have."

Consumer NZ CEO Jon Duffy said patients should seek independent advice before upsizing their fertility treatment.

"Those options need to come with an evidence base that backs them up. If providers are claiming a benefit from IVF, they should be able to back that up with robust scientific evidence." 

Murray said his patients are informed of the evidence.

"Often this is something that is initiated by them and if you've got a couple in front of you, they've been trying for many years, often before the add-on discussion comes up they've perhaps done two or three rounds of IVF already," he said. 

"If we dismissed every idea they came forward with from things they've perhaps read online I think that would be a very patriarchal thing to do."

Stories about add-ons in overseas media have led to changes. In the UK, a traffic light system ranks add-ons according to how effective they have proven to be.

In New Zealand two rounds of IVF treatment are funded - but not for everyone.

Limited public funding means waitlists. In Auckland it's currently 12 to 18 months. And to qualify you must meet certain criteria - age, BMI and at least a year of trying naturally first. 

That BMI criteria is disproportionately shutting Māori  and Pasifika women out. The average BMI for non-Māori  women is 26.9. For Māori , it's 30.6. 

Professor of Nutrition Elaine Rush describes it as a crude measure.

"We've known for quite a long time that for the same BMI, Māori and Pacific have more muscle and less fat than European."

Rush suggests physical fitness might be a fairer measure than BMI.  

One University of Otago study describes the BMI criteria as an example of 'institutional racism'. Farquhar said the threshold can be punitive for Pacific and Māori women.

"Maybe we should be looking at having BMI thresholds along ethnicity lines and not just a blunt one size fits all."

Māori Party co-leader Debbie Ngarewa-Packer also slammed the BMI restrictions as racist.

"BMI full stop discriminates against Māori  and Pasifika. Today we would class that as a form of fat shaming. BMI has been crafted by - I hate to say it - crafted by white supremacists who actually don't want to see any other body shapes," she told Newshub Nation.  

Advocates also say the criteria are unfair to same-sex couples who have to try 12 cycles of private insemination, if they qualify at all, and to those with unexplained infertility, who have to try for five years naturally first.

If the criteria are widened, Farquhar said the funding needs to increase too, otherwise that dreaded wait-list will only grow.

"There are inequities. There are people who simply won't be able to become parents because they can't afford to pay for it.”