A new clinical trial investigating the optimal gap between first and second COVID-19 vaccine doses for pregnant women is set to launch in England today.

The Preg-CoV study, backed by £7.5 million of government funding and led by St George’s, University of London,  will involve over 600 pregnant women between 18 and 44 years old being vaccinated with either the Pfizer/BioNTech or the Moderna vaccine. It will provide clinical trial data on the immune response to vaccination at either the shorter interval of four to six weeks, or the longer interval of eight to 12 weeks.

The Pfizer/BioNTech and Moderna vaccines were recommended by the independent experts at the Joint Committee on Vaccination and Immunisation (JCVI) for pregnant women in the UK, after 130,000 pregnant women were vaccinated in the US with no safety concerns raised.

Data published last week by NHS England and the University of Oxford also shows no pregnant women who have had both doses of a vaccine have been admitted to hospital with COVID-19.

In addition, just three pregnant women have been admitted after having their first dose, meaning 98% of those admitted to hospital have not received a jab.

“Pregnant women are more likely to get seriously ill from COVID-19 and we know that vaccines are safe for them and make a huge difference. This government-backed trial will provide more data about how we can best protect pregnant women and their babies, and we can use this evidence to inform future vaccination programmes,” said Nadhim Zahawi Minister for COVID-19 Vaccine Deployment.

Initial results on how the vaccines are protecting these individuals from COVID-19 are expected by the end of the year.