It's a growing trend across Australia, and many expectant mums and dads are taking a firm stance to protect their unborn babies. They are introducing self-imposed "No Vax, No Visit" policies when it comes to family and friends meeting their precious new additions.

Whooping cough, or pertussis as it is medically known, is a highly contagious and potentially fatal infection for babies, which can be prevented through immunisation. However, newborn babies aren't able to receive their first whooping cough vaccination until they are six-weeks-old. To protect newborns during this vulnerable period parents must immunise themselves and rely on the herd immunity of visiting friends and family.

Expectant mums are able to receive a free whooping cough booster during their third trimester of pregnancy. The antibodies from the vaccine pass through to the womb to provide some immunity to the baby through the placenta.

Additionally, fathers, grandparents and other adult friends and family members who are likely to come in close contact with the newborn baby are being encouraged to receive a whooping cough vaccination booster at least two weeks before coming into contact with the baby. Doing this greatly reduces the chances of passing on the deadly pertussis bacteria to the baby.

Many expectant parents support this to the extent that they are limiting contact with their newborns to only adults who have received their booster. This strict "No Vax, No Visit" rule allows parents to protect their family from unnecessary tragedy.

Katie Markwick is a mother-of-three who recently brought her premature twins home from hospital. Being understandably protective of her vulnerable babies, Katie believes a "No Vax, No Visit" approach is essential for protecting her newborns.

"I sent a group message to my family asking that they check that their vaccinations are up-to-date, or to stay away until the first lot of needles at six weeks.

"I asked, and generally my request has been received well. I know I can't protect them from everyone and everything, but I can just do my best. With 36 weekers, they aren't strong enough to protect themselves, so that's my job!"

And what about Katie's family members who don't want to a vaccination booster?

"Those who weren't vaccinated for whatever reason, and don't want to be vaccinated, are just staying away until the babies get vaccinated. Overall, people have been very understanding of our wishes."

Grandparents and other family members are largely happy to oblige when they learn that getting their whooping cough vaccination booster will protect their grandchild.

Soon-to-be grandmother, Kate Pearce had no issue with getting her booster, "I was only too happy to have my whooping cough vaccine and anyone who will be in contact with a newborn should understand the importance."

Grandmother-of-three, Johanne Allen has a new grand-baby on the way and also agrees that being vaccinated is best practice for family members. "It's the right thing to do to make sure our babies are safe. I have my script ready and getting it next month to make sure I'm safe for my daughter-in-law's newborn."

Sunday Soldiers create kids' t-shirts to raise money for vaccination awareness

However, not all expectant mums are as keen on the "No Vax, No Visit" notion. Gemma King is 38 weeks pregnant with her fourth child and although equally as protective of her unborn baby, is taking a different approach to preventing against a whopping cough infection.

"My GP insisted I got the booster at 28 weeks to ensure that there were enough antibodies produced by me to transfer over to the baby in time.

"My partner also got his booster. I believe too that if people have coughs, colds or are generally unwell they shouldn't go near a newborn, it's courtesy. Not taking the baby to populated places unnecessarily and keeping a low profile can be very helpful in reducing risk, so my GP said.

"You can't make the herd comply, but you can take yourself away from the herd."

So will Gemma be imposing a "No Vax, No Visit" rule on her friends and family?

"No, I will be asking that for anyone who is sick to welcome the baby when they are well. Who honestly sees a new baby when they are sick anyway?"

While not everyone will agree on immunisation when it comes to whooping cough, it can't be ignored that the disease is fatal for one in 200 infants under the age of six months who contract the infection.

For more information on whooping cough prevention visit Immunise Australia