Research finds better pregnancy outcomes among vaccinated women

Research led by Associate Professor Lisa Hui from the Department of Obstetrics and Gynaecology has confirmed that women who have been vaccinated against COVID-19 have better pregnancy outcomes, with fewer preterm births and stillbirths. The study provides the first large-scale evidence of vaccine safety among pregnant women in Australia. Published in the American Journal of Obstetrics and Gynaecology, the multicentre study analysed the outcomes of 32,536 births between 2021-2022.

Sarah Marcola with her baby.Sarah Marcola, a professional staff member with the Department of Obstetrics and Gynaecology, pictured with her baby daughter, Emily. Image courtesy of the Herald Sun.

While the overall maternal COVID-19 vaccination coverage rose steadily following the June 2021 ATAGI recommendations for vaccination in pregnancy, the study showed a significant disparity in vaccine uptake by sociodemographic features. Overall, 85% of women giving birth at the end of March 2022 received at least one dose of the COVID-19 vaccine.  Vaccinated women were significantly more likely to be older, be having their first child, be non-smoking, have no need for an interpreter, be of higher socioeconomic status, and be vaccinated against pertussis and influenza. Vaccination status also varied by region of birth.

“We conducted this multicentre study to provide robust local evidence on mRNA COVID-19 vaccination and perinatal outcomes including stillbirth, preterm birth and congenital anomalies,” said Professor Lisa Hui.

“COVID-19 vaccination during pregnancy was not associated with any adverse impacts on foetal growth or development, and was associated with benefits in terms of lower rates of stillbirth, preterm birth, and neonatal intensive care.

“Even among the women who contracted COVID-19 infection during pregnancy, vaccination still had benefits. Vaccinated women were less likely to have a preterm birth than unvaccinated women with COVID-19 infection during pregnancy.

“The difference in vaccination rates by region of maternal birth really highlights the need to engage local communities in the public health messaging, and to ensure that we remove any barriers to accessing accurate health information and medical care for under-served communities.”