An oversupply of medical graduates that wasn't predicted until 2017 has left would-be junior doctors out of jobs.

In a reversal of the previous workforce shortage, trainee doctors have this year been faced with job uncertainty as district health boards grapple with "unanticipated" interest in hospital placements.

Last-minute internship positions have had to be created in hospitals nationwide to deal with the influx, forcing a two-week delay in job offers.

While 376 New Zealand residents were finally offered positions last week - 49 more internships than in 2012 - international students who have trained here have not been so lucky. An estimated 30 students have missed out, New Zealand Medical Students Association president Phillip Chao says.

"These are extremely intelligent, brilliant students who have funded their own education here, and some are in massive debt. We feel they should have the opportunity to give back to the New Zealand healthcare system if that is their choice. It's just poor planning - we've known this was going to happen since 2008."

All graduates have to complete a one-year internship to gain registration.

Health Workforce New Zealand executive chairman Des Gorman said a combination of events had led to the struggle to secure enough internships from DHBs.

"We've just had an extraordinary year in terms of a whole range of challenges that we thought would happen in the next three to four years, and it's happened in a rush."

Graduates were no longer heading overseas, as job markets in Australia, the United States and Britain were oversaturated. Previously, one in four went abroad, a number now estimated to be one in 20.

More students were being trained here, and there was a "log-jam" at the upper end as senior doctors stayed in their jobs.

But he made no apologies for non-New Zealand residents missing out. "We've never guaranteed them jobs . . . The reason for increasing numbers of students at our medical schools is so we can get more New Zealand doctors."

The Health Ministry was also contending with how to find places for between 80 and 100 Australian-trained Kiwis who were expected to head home for work.

But New Zealand Medical Association chairman Mark Peterson said figures predicting the influx in 2017 were "shonky", and there should not have been such a scramble to create roles.

". . . It does seem surprising that we've only just realised we need to find places for all of them. It wasn't well managed."

A total of 277 students applied for an internship in the Wellington region - Capital & Coast, Wairarapa and Hutt Valley - and 43 were offered positions. This was three more than in previous years, a CCDHB spokesman said.

After residency, interns were chosen based on academic scores, interview results and references. No non-residents were offered roles.

"The mismatch is an absolute failure . . . that's by no means the end of the matter," Green Party health spokesman Kevin Hague said.

GRADUATES FACING FEWER OPPORTUNITIES

Former Onslow College student Kenji Takahashi has spent more than $300,000 on medical training here - but no hospital wants to employ him.

The Japanese national has lived in New Zealand for 10 years and is in his final year of medical school in Dunedin. He will graduate in November, and while his friends are being offered jobs, he is not.

"I'm very disappointed and frustrated at the moment," he said. "I'm very happy for my friends all getting a job, but I planned to live with my friends so we could all work together but that has just fallen apart.

"This is my home, I've spent the last 10 years here from my teenage years, I have so many friends here and I know the healthcare system."

Mr Takahashi, 26, who wanted to become a paediatrician, has now been forced to look for jobs overseas.

He hoped the Government addressed the problem, so as not to lose locally trained doctors. "It [is] a waste of valuable workforce for the country."

In Australia last year, 162 international students were left without jobs.

In response, that government created 116 new internships. District health boards prioritise New Zealand citizens or residents, for whom they receive a $30,000-a-year subsidy.

Mr Takahashi is on a student visa, but was hoping to be sponsored because doctors - both GPs and specialists - are on the Immigration New Zealand skills shortage list. In previous years, interns have been sponsored.