To identify the best interval between vaccine doses, during and following pregnancy, more volunteers are urgently needed to join the Preg-CoV study.
Run at Heartlands Hospital in Birmingham and the Princess Royal Hospital, Telford, the study compares vaccines currently being used for the UK vaccination programme – Pfizer/BioNTech and Moderna – as well as new vaccines as they are approved.
The study will provide vital clinical trial data on the immune response to vaccination at different dose intervals - either four to six weeks or eight to 10 weeks.
Hundreds of pregnant women are needed in order to help provide further findings key to protecting more women and shaping future vaccine guidelines.
The study launched in August, and will involve 600 pregnant women, across 14 sites across England.
Volunteers will be closely monitored by health professionals throughout their pregnancy and following the birth.
Raj Watts, research midwife at Birmingham Heartlands Hospital, said: “Our patients have really appreciated the chance to contribute to Covid research.
"They have been on board with the vaccination programme and we are pleased to offer them the opportunity to take part in this study to improve safety of themselves and their babies.”
The current UK guidance is that Covid-19 vaccination should be offered to pregnant women at the same time as the rest of the population.
Chief investigator and professor of paediatric infectious diseases at St George's, University of London, Professor Paul Heath said: “Over two hundred and fifty thousand pregnant women have now been vaccinated with Covid-19 vaccines in both the US and the UK, with no major safety concerns reported.
"But we do not yet know the best schedule to use to provide the maximal protection for pregnant women against Covid-19 and this is what we are addressing in this study.
“We need even more pregnant women across the country to join the study.
"Not only will they receive special monitoring and support around their vaccines, but they will help shape future guidelines and protect pregnant women in the future. It is a really worthwhile, helpful thing to do.”
Pregnant women in the study will receive monitoring and additional support through study visits.
They will also be provided a 24-hour phone line should they have any questions for the trial team and an electronic diary to record any symptoms.
They will be reimbursed for travel to their study appointments.
Once successfully enrolled, most participants will be randomised to receive two doses of an approved Covid-19 vaccine with either a short-time interval or a long-time interval between doses, with the majority of volunteers blinded to which vaccine they receive.
For some participants this means they will receive their second dose after delivery.
The study is seeking low-risk, carrying a single baby, pregnant women aged 18 to 45 years-old and between 13-34 weeks gestation.
People can find out more by visiting the study’s website.