Pregnant women are now safe from whooping cough in the country's busiest birthing region.

Counties Manukau District Health Board has agreed to fund whooping cough immunisation for pregnant women after 20 weeks.

The decision means expectant mums can see their GPs to be immunised against the deadly cough at no cost.

The move is seen as "a protective barrier" for the most vulnerable – babies under 12 months old, board spokeswoman Lauren Young says.

"We're in the middle of a whooping cough epidemic that can have devastating effects on babies," she says.

For every 100 infants with whooping cough, around 70 will be hospitalised, seven will require intensive care and one or two will suffer permanent medical complications such as brain damage or death.

Auckland Regional Public Health Service says antibodies made by the mother in response to being immunised are passed to her baby across the placenta during the final few weeks of pregnancy.

The antibodies should help protect the baby for around six weeks and will eventually wear off.

It recommends babies have the vaccination at six weeks then followed at three months and five months.

Babies will not be protected until they receive all three doses.

Phone Healthline on 0800611116, visit your doctor or visit go the arphs.govt.nz for more information on whooping cough.

Go to easterncourier.co.nz and click Latest Edition to see the effects of whooping cough.

- © Fairfax NZ News