Second trimester (14–26 weeks)

Key facts

  • Vaccination against whooping cough is recommended for pregnant women in their second or third trimester, between 20 and 32 weeks.

  • Vaccination against influenza is also recommended for women who did not have the vaccine during their first trimester. You can have both the whooping cough and influenza vaccines at the same time.

  • Whooping cough and influenza vaccination during pregnancy is safe.

Last updated on 22 September 2026.

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What vaccines are recommended in my second trimester?

Whooping cough (pertussis)

When you are pregnant, it is strongly recommended that you get vaccinated against whooping cough (also known as pertussis). Women should have a whooping cough vaccination in each of their pregnancies, ideally between 20 and 32 weeks. The whooping cough vaccine will protect both your baby and you from this serious infectious disease. Studies indicate that 9 out of 10 babies under three months of age are protected against whooping cough if their mothers received the whooping cough vaccine during pregnancy.1,2

Influenza

Women who did not get the influenza vaccine in their first trimester are advised to get it in their second trimester. Getting vaccinated against influenza (commonly called ‘the flu’) is also recommended to protect both you and your baby from one of the most common and highly contagious viral infections. Babies can’t be vaccinated against influenza until they are 6 months old. Until then, the vaccine you get during pregnancy will provide your baby with the best early protection from the influenza virus.

Pregnant women who have received the previous year’s influenza vaccine in the first trimester of pregnancy are recommended to be revaccinated with the current season’s vaccine later in the pregnancy.

Both whooping cough and influenza vaccines are free for all pregnant women in Australia. It is recommended that you get both vaccines, each time you are pregnant. You can have both the whooping cough and influenza vaccines at the same time.

What do I need to do before the vaccination?

There’s no need to do anything special to get ready for your vaccination.

The best time to have the whooping cough vaccination is between 20 and 32 weeks of pregnancy. This is when the transfer of protective antibodies from you to your baby is most effective and will provide the best protection for your baby after birth. However, the vaccine can be delivered anytime from 20 weeks of pregnancy up to delivery.3

You can get the influenza vaccination at any time during your pregnancy, and at any time of the year.

The midwife or trained immunisation nurse at your antenatal clinic may be able to vaccinate you against whooping cough and influenza. If not, you can go to your GP, local council clinic or pharmacy. Most GPs will need you to make an appointment if you require a vaccine. 

What do I need to do after the vaccination?

Most people have no reaction to the whooping cough and influenza vaccines. Some people have mild reactions that last between 12 and 24 hours and are easily treated at home.

If your symptoms last longer than a couple of days, or if you are worried about how you feel after your vaccination, you can get help from your doctor, or your nearest emergency department, or by calling Health Direct on 1800 022 222.

A very small number of people have a severe allergic reaction to vaccines called ‘anaphylaxis’, where they can develop swelling, hives, breathing difficulties, lowered blood pressure and in severe cases, shock. Anaphylactic reactions are very rare – they occur in about one in a million people who have a vaccination.4 Midwives, nurses and GPs are trained to respond to an anaphylactic reaction with quick delivery of adrenaline.

Read more about the rare but serious side effects

When do I need my next vaccination?

If you have not yet had a whooping cough or influenza vaccination by the end of your second trimester, you are able to get them in your third trimester.

It is strongly recommended that pregnant women get vaccinated against both whooping cough and influenza each time they are pregnant.

You can also receive a respiratory syncytial virus (RSV) vaccination between 28 and 36 weeks of pregnancy, in your third trimester.

What if I still have questions?

You can find more information on vaccination in pregnancy and at birth in our Resources section, and on these pages:

If you still have some questions remaining, write them down so that you can ask your midwife, nurse or GP at your next appointment.

  1. Amirthalingam G, Andrews N, Campbell H, et al. Effectiveness of maternal pertussis vaccination in England: an observational study. Lancet 2014; 384(9953):1521−8. Available from: https://doi.org/10.1016/S0140-6736(14)60686-3.  
  2. Baxter R, Bartlett J, Fireman B, et al. Effectiveness of vaccination during pregnancy to prevent infant pertussis. Pediatrics 2017;139(5): e20164091. Available from: https://doi.org/10.1542/peds.2016-4091.
  3. Australian Technical Advisory Group on Immunisation (ATAGI). The Australian Immunisation Handbook. Available from: https://immunisationhandbook.health.gov.au/.
  4. McNeil MM, Weintraub ES, Duffy J, et al. Risk of anaphylaxis after vaccination in children and adults. Journal of Allergy and Clinical Immunology 2016;137:868−78. Available from: 16/j.jaci.2015.07.048 https://doi.org/10.1016/j.jaci.2015.07.048.