Health Minister Tony Ryall says pregnant women are more likely to be hospitalised with flu than others, and should make sure they have a flu jab.
Mr Ryall launched the annual flu vaccination campaign at Wellington Hospital's high-risk maternity clinic on Tuesday.
Last year a record 1.25 million people had the jab, and Mr Ryall says this year's aim is to match that at least.
"If you're pregnant you're 18 times more likely to end up in hospital with the flu than if you weren't," he says, "so it's a really important preventive measure that helps protect mum and baby.
"So that's our big push this year ... but also we're wanting to get that 1.25 million New Zealanders immunised."
Mr Ryall says immunisation in pregnancy also protects the baby during the first few months of life.
Vaccination is free for those at high risk of complications, which includes pregnant women, those 65 and older, and anyone under 65 with long-term health conditions.