Vaccinations in pregnancy.

Vaccinations are a cost-effective means of preventing disease. They may be recommended primarily for maternal benefit or for prevention of intrauterine fetal or early neonatal infection. Data from the International Network of Obstetric Survey Systems relating to the COVID-19 pandemic showed that for all countries studied (the UK, the Netherlands, Norway, Denmark, Finland and Italy), at least 80% of pregnant women admitted to critical care were unvaccinated. In the UK this figure was 98%. The MBRRACE-UK 2014 report, covering 2009-2012 during the H1N1 epidemic, demonstrated that one in eleven maternal mortalities were directly from influenza virus: more than half could have been prevented by the flu vaccine in pregnancy. Research is ongoing to develop additional vaccines for infections that cause detrimental effects to pregnant women and their infants. Theoretical concerns regarding adverse effects to the fetus and lack of efficacy have, in general, not been confirmed by clinical evidence. Nevertheless, live attenuated vaccines remain contraindicated due to risk of fetal infection. As with any clinical decision, advice on antenatal vaccination should be based on the balance of risks and benefits to mother and fetus. This article aims to guide such decisions by discussing the issues surrounding commonly used vaccines and presenting current UK guidelines.