Ardern's partner Clarke Gayford is the primary caregiver for Neve. He has recently returned to work as a presenter on a television show about fishing.
"Filming for him is a sporadic thing," Ardern said. "So when he's away, we work around that. But primarily his number one job, still, is dad."
Several MPs have also recently given birth, and Ardern said she gave plenty of credit to Speaker Trevor Mallard for making Parliament a more baby-friendly place.
"He's really tried to set the tone," she said. "He's tried to create a flexible environment."
She said she has little planned for the holiday period other than spending time with her family, and so will be letting Neve set the routine. She said Neve is growing fast.
"She can sit for a few seconds before she topples over. So she's partially sitting up. She's 6 months this week, it's moved really quickly. But it's a lovely stage," Ardern said. "I'll be spending a lot of time with her over the holidays and that's the thing I'm looking forward to the most."
Parliament is in its final sitting week for 2018 and resumes in February.
- AP