Influenza and pertussis vaccination of women during pregnancy in Victoria, 2015–2017

To the Editor: We read with interest the recent publication by Rowe and colleagues.1 The authors reported low influenza vaccine coverage (39%) among pregnant women in Victoria from 2015 to 2017. Individual‐level factors associated with this finding included greater maternal age, primigravidity, early antenatal care and GP‐led antenatal care.1

As the authors accurately concluded, integrating vaccine delivery into antenatal care pathways is important to improve pregnant women's vaccination coverage.1 Our team reported on this previously, with coverage approximating 90% achieved by introducing standing orders for midwives.2 In collaboration with key stakeholders from six Victorian maternity services, a Monash University‐led project funded by Better Care Victoria is currently underway to implement integrated vaccination strategies and measure the cost and magnitude of improvement in maternal immunisation coverage in Victoria,3 the results of which will be available by the end of 2019.

One of the key findings in the article by Rowe and colleagues1 is higher odds of influenza vaccination in women who gave birth after 37 weeks' gestation compared with women who gave birth before 28 weeks (adjusted odds ratio [aOR], 4.74; 95% CI, 3.54–6.35). A similar finding was reported for women who gave birth between 28 and 36 weeks gestation (aOR, 4.13; 95% CI, 3.07–5.56).1 This finding has two important implications.

Firstly, it may indicate a potential beneficial effect of influenza vaccine received by pregnant women in reducing pre‐term birth (< 37 weeks' gestation). This is consistent with a recent systematic review and meta‐analysis that reported inactivated influenza vaccine to have a protective effect against pre‐term birth and low birth weight.4

Secondly, this finding may serve as an opportunity to emphasise the safety and benefits of influenza vaccines on perinatal outcomes. As the authors alluded to in their discussion, pregnant women tend to view influenza as primarily a health risk for themselves rather than for their infants.1 Given the importance of health care providers' recommendations in encouraging influenza vaccination among pregnant women, timely dissemination of the potential benefit in lowering the chance of pre‐term birth could further empower health care providers to recommend influenza vaccines to pregnant women.5