It's well known that getting children immunised helps protect them from some serious diseases. What is less well known is that women can get immunised during pregnancy for whooping cough and the flu. Immunisation during pregnancy helps protect mums and babies from the harmful effects of these diseases.

Dr Pat Tuohy, the Ministry of Health's Chief Advisor - Child and Youth Health, stresses the importance of immunisation during pregnancy.

"Whooping cough can cause babies to become seriously ill, and can sometimes be deadly. And getting the flu when you are pregnant can be serious for both mum and baby. That's why immunisations during pregnancy for whooping cough and the flu are recommended. They're free and have a proven safety record."

Whooping cough and the flu are common diseases in New Zealand. We have regular whooping cough outbreaks. In the 2010-2013 outbreak over 800 babies got whooping cough and three children died. Often it is passed to babies from adults - family members, parents and grandparents. This is why the Ministry of Health recommends that other adults in close contact with babies are immunised against whooping cough - though these adult boosters are not funded.

Flu is also common, with influenza-like illnesses affecting around 50,000 New Zealanders last year. And pregnant women are five times more likely to be admitted to hospital when suffering from influenza-related complications than women who are not pregnant. When you're pregnant the best way to protect yourself against the flu is by getting immunised.

The reasons these vaccinations provide protection is that although the vaccine doesn't pass on to the baby, mothers can pass on their immunity t. Receiving one immunisation against influenza during pregnancy can help protect both mother and baby, both as a fetus and newborn. Immunisation during pregnancy stimulates the mother's immune system to make protective cells called antibodies. As well as protecting the mother from getting sick from influenza they also travel across the placenta into her baby's blood stream and help protect the baby for up to six months after birth.

It is really important to protect babies when they are most vulnerable. Although babies receive immunisations against whooping cough, they don't develop the best protection until after they have completed the third dose at 5 months. By being immunised during pregnancy the mother's immunity can be passed on to the baby. Research has shown that immunisation against whooping cough during pregnancy protects nine out of ten babies in their first few weeks of life, until they are fully immunised. Immunising on time is important to keep that protection up.

This year's National Immunisation Week is on May 2 to-8 with the theme of 'protecting baby starts in pregnancy'. Expectant mums are encouraged to enrol early with a midwife and GP, be immunised during pregnancy, and immunise baby on time.

"Enrolling with a GP and midwife early in the pregnancy helps ensure mother and baby get the care they need," says Bronwen Pelvin, the Ministry of Health's Principal Advisor - Maternity.

For more information on Immunisation, go to www.immunise.govt.nz, www.immune.org.nz, www.fightflu.co.nz or phone 0800 IMMUNE