Napier man Brett Wills had agreed to be a stay at home dad, but the "poor guy" wasn't bargaining on four at once.

Brett and wife Joanne Wills on Saturday became the proud parents of New Zealand's first set of quadruplets in four years.

Fraternal siblings Esther (1.024kg), Lucy (1.461kg), Jonathan (1.647kg) and Oliver (1.316kg) were born in that order at Wellington Regional Hospital over a 15-minute period from about 2pm.

The babies were premature, 31 weeks and one day to specific, and birthed via a planned caesarean section. There were no complications and the four are now being cared for on ventilators in the neonatal intensive care unit of the hospital.

Joanne says her first concern when she heard she was having quadruplets was that she'd have to think of four suitable names.

That, and Brett.

"The poor guy agreed to be a stay-at-home dad. He's been enjoying it, but then he's found out he's going to be having another four.

"He is coping amazingly."

Napier mum Joanne Wills with her baby Oliver, one her four new quadruplets. Photo / Supplied

Joanne works as a consultant at Australian software company TechnologyOne and is also a skipper for Hawke's Bay Coastguard.

The couple already have one child together, 20-month-old Peter, but Joanne said this pregnancy was on another level - as if it was her first pregnancy but "on steroids".

"Everything goes a lot faster. You've got to go into maternity leave a couple of months earlier, you just have to do your planning a lot earlier. We're very busy."

Joanne said they found out they were having quadruplets about eight weeks into the pregnancy.

"We had a scan and suddenly that scan was a bit different," Joanne said.

Esther is the smallest of the quadruplets, weighing in at 1.024kg. Photo / Supplied

"You're a bit shocked and trying to get your head around it. All I thought at first was how many names I'd have to come up with."

She said they had only finally settled on names for each of the quadruplets on the day after the births.

"We thought we knew what we were going for, but then you've got to meet your babies before you actually name them."

Joanne said she has held each of the four in her arms, but hasn't had a chance to bring them all together yet as they still required support through incubators.

Fraternal siblings Esther, Lucy, Jonathan and Oliver were born at Wellington Regional Hospital on Saturday. Photo / NZME

They will stay in incubators until their lungs are strong enough.

"It will happen, good things take time," Joanne said.

Joanne said the new additions to the family were a bit more than they bargained for when going for a second pregnancy.

She said rest of the family hadn't had the chance to see the quads in person due to Covid restrictions, but they were all "terribly excited".

The last quadruplets born in New Zealand were Quinn, Indie, Hudson and Molly to Timaru couple Kendall and Joshua MacDonald on August 15, 2018.

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- by James Pocock, Hawkes Bay Today