A Palmerston North mother Jess Tahi had the tongue-tie, or frenulum, snipped on her six-week-old baby Aniwa in March last year.
It was done by a GP, and Mrs Tahi, a nurse, said she was struggling to breastfeed Aniwa at the time.
Mrs Tahi said it was a difficult and painful experience.
"And feeding wasn't very productive - like it would take a long time, she would be quite unsettled before and after it. Then the procedure itself was great and yeah she recovered very well from it. And I found afterwards you know she was a lot better."
Her experience is echoed in today's study involving infants who had tongue-tie surgery at Hokowhitu Medical Centre in Palmerston North over seven months from late 2016.
The study's author GP Sam Illing said when babies with a tongue-tie who were having trouble feeding had it treated, a third were cured and able to feed normally.
He said: "Ninety-seven percent of parents were happy with the procedure and happy with the effect it had on their child. And we can also say that a third of children who had been bottle feeding were able to start breastfeeding."
Dr Illing said it also reduced the pain some mothers experienced while breastfeeding and shortened the time needed for feeding.
"These babies that ... had a tongue-tie and were having issues with feeding often took quite a long time to feed and each breastfeed was often taking on average around 40 minutes. And that improved down to about 20 minutes afterwards."
He added the procedure was well tolerated, apart from one baby who needed to be fed by a syringe for two weeks after the snip, before resuming breastfeeding.
But Wellington anaesthetist Graham Sharpe said the study was weak.
"This is not a medical study or a scientific study. It's actually a consumer satisfaction survey and it looks the same sort of survey one might expect reviewing a restaurant or a new washing machine."
He said the study drew conclusions on the experience of just 176 babies and their parents, and makes tenuous claims.
"They refer to, and I'm quoting you, five widely accepted randomised control trials regarding frenotomy and the effect on breastfeeding. I was actually quite amused by that because those five trials total only 302 cases. So assuming that half of them were a control group, they're drawing a very long bow from something like 150 cases."
Dr Sharpe believed tongue-tie surgery is over-diagnosed and treated, potentially harmful, and should only be done or supervised by a surgeon.
He said he couldn't understand why the study was done.
"I also question the ethics of publishing something that's such a poorly designed paper because there's no control group, and it looks at parental satisfaction and impressions of its value. Those are weak criteria. They don't tell us anything."
Dr Illing told RNZ having a control group wasn't feasible, but the findings were worthwhile.
He said: "A randomised control study where you would do that would be the gold standard sort of study to do, but that wasn't something within our ability to do. So instead, asking parents and seeing what their response was, what their experience was, we'd get a different perspective to some of the other literature that's out there."
He added the procedure, if done properly as it was at the medical centre, was safe and effective.
There are differences of opinion over the procedure.
The Health Ministry held a meeting on it in April to hear viewpoints.
It said in a statement yesterday that the consensus from the meeting was that multidisciplinary guidance was wanted and needed.
"Several issues were identified including a lack of consistent information for consumers about the risks and benefits of surgical treatment for tongue-tie; inconsistent and inequitable access to treatment when indicated; and a lack of nationally consistent breastfeeding support in the community."
The Ministry said it was leading development of this guidance, working with an external advisory group consisting of key stakeholders. It said it was aiming to provide guidance by April next year.