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Pregnant women needed for COVID-19 vaccine study running in Southampton

image for Preg-COV promo

Pregnant women in Southampton are being called upon to take part in the UK’s largest clinical study investigating the best gap between first and second COVID-19 vaccine doses for pregnant women.

The Preg-CoV study, which will take place in the NIHR Southampton Clinical Research Facility (CRF) at University Hospital Southampton NHS Foundation Trust, is looking for volunteers to take part and help shape future national and international guidance around COVID-19 vaccination and pregnancy.

The study will compare vaccines that are currently being used for the UK vaccination programme (Pfizer/BioNTech and Moderna) as well as new vaccines as they are approved. It 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. This data will help determine the best dosage interval and tell us more about how the vaccine works to protect pregnant mothers and their babies against COVID-19.

Volunteers for the study will need to be between 18 and 45-years-old, generally healthy and low-risk, carrying a single baby and between 13 and 34 weeks gestation.

They will be closely monitored by health professionals throughout their pregnancy and following the birth, receiving additional support through study visits compared to those who receive their vaccine outside of the study.

Volunteers will also be provided with a 24-hour phone line should they have any questions for the study team, and will be reimbursed for travel to their study appointments.

Those interested in taking part can find out more by visiting the study website or contacting the local Southampton study team on

Recent data shows that 1 in 5 of the most critically ill COVID-19 patients are pregnant women who have not been vaccinated.

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. COVID-19 vaccines are safe and effective for pregnant women, and there is a clinical consensus that it is the best way to protect pregnant women and their babies from COVID.

Data from UKHSA showed that over 84,600 pregnant women have received the first dose of the life-saving COVID-19 jab, and around 80,700 have received their second dose.

Further pregnancy-specific research is currently happening in the UK to provide more data around the most effective vaccines, and the best gap between vaccine doses for pregnant women.

The Preg-CoV study will involve 600 pregnant women, across 14 NIHR-supported sites. Once successfully enrolled, most volunteers will be randomised to receive two doses of an approved COVID-19 vaccine with either a short-time interval (4-6 weeks) or a long-time interval (8-10 weeks) between doses, with the majority of volunteers blinded to which vaccine they receive.

For some volunteers, this means they will receive their second dose after delivery. Participants will receive a single dose if they have already received their first dose or if they just need a booster (3rd) dose. The study is also recruiting participants who have already had two doses of a COVID-19 vaccine in the community.

Dr Chrissie Jones, Associate Professor in Paediatric Infectious Diseases at the University of Southampton and local investigator for the study, said:

“We are inviting women who are pregnant and have not yet had any COVID-19 vaccines, as well as those that have already had one or two doses of a COVID-19 vaccine, to take part in the Preg-CoV study.

“We now have lots of ‘real-world’ data to show that these vaccines are safe and effective, now we are investigating the best timing of COVID-19 vaccines in pregnancy to ensure that women have the best protection from these vaccines for themselves and their babies.”

Debbie, a volunteer on the study, said:

“Becoming pregnant during the pandemic, my main concern was will my baby be okay. So in fact, it was only after joining the study that I slowly began to relax and begin to enjoy my pregnancy with less stress and fear around COVID.

“I couldn’t wait for the study to start and felt more confident and comfortable about having the vaccine this way than heading to a local drop in centre. It gave me the confidence that I was going to be looked after during my vaccination journey. It provided everything I needed, which was health professionals such as a midwife, doctors and nurses who had the knowledge and experience around the vaccinations and the effects of COVID during pregnancy.

“I had so many questions and concerns as I joined the study which were all addressed by the study team. I even got to hear my baby's heartbeat and the thorough assessment I underwent before receiving my first vaccination gave me the comfort and confidence that myself and my baby were in safe hands.

“I feel more pregnant women who are on the fence or concerned about what is best to do about getting vaccinated should definitely join the study. It changed my whole pregnancy experience being pregnant during a pandemic to a more positive experience and I have felt much safer as a pregnant woman since joining.”

Georgina, another participant in the study explained:

“It is both interesting and rewarding to take part in this study. I wanted to get involved because I wanted to give something back.

“When the trial came about it seemed like the perfect opportunity to help medical research, while also getting vaccinated and extra care in my pregnancy.”

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.”