Pregnant women in the UK can now be offered a Covid-19 vaccination, government advisers said on Friday, but should not have the Oxford/AstraZeneca jab.
The Joint Committee on Vaccination and Immunisation (JCVI) recommended that expectant mothers, who up to now have been advised not to have a jab, should only have the BioNTech/Pfizer or Moderna shot.
The exclusion of the AstraZeneca jab, the mainstay of the UK’s vaccine programme, reflected a lack of data on how it performed in pregnant women rather than any specific safety concerns, officials said.
The advice represents another blow to the Anglo-Swedish company. Last week the UK said people under-30s should, wherever possible, be given an alternative vaccine to the AstraZeneca, after it was linked to a blood disorder that a very small number of people developed post-immunisation.
Denmark this week banned the use of AstraZeneca vaccine while a number of other European countries have put in place strict guidance, limiting its use to the over-55s, over-60s or in some cases people over 65.
The JCVI guidance previously for pregnant woman was that there was insufficient evidence to recommend Covid-19 vaccines even though the available data did not indicate any safety concern.
Data from the US on 90,000 pregnant women who have been vaccinated — mainly with BioNTech/Pfizer and Moderna vaccines, which are based on mRNA technology — had not raised any issues, the JCVI said.
The AstraZeneca jab is based on different technology known as adenovirus. US health authorities announced this week they were suspending the use of another adenoviral vaccine by Johnson & Johnson while they investigate several incidents of rare blood clots.
The vaccination programme in the UK, one of the more advanced in the world, is starting to move down the age groups and will soon target the under-40s cohort that accounts for most pregnancies.
“Based on these data, the JCVI advises that it is preferable for pregnant women in the UK to be offered the BioNTech/Pfizer or Moderna vaccines where available. There is no evidence to suggest that other vaccines are unsafe for pregnant women, but more research is needed,” it said.
No specific risk factors had been identified that suggested pregnancy made people more susceptible to post-vaccination blood clots, officials stressed. They said vaccination could safely take place at any stage of pregnancy but some women might prefer to wait until after the first trimester when most of the foetal development takes place.
Although uncommon, severe illness due to coronavirus is more likely in later pregnancy and expectant mothers who contract symptomatic Covid-19 are two to three times more likely to give birth to their baby prematurely, the JCVI said.
Prof Wei Shen Lim, Covid-19 chair for the JCVI, encouraged pregnant women “to discuss the risks and benefits with their clinician — those at increased risk of severe outcomes from Covid-19 are encouraged to promptly take up the offer of vaccination when offered.
“There have been no specific safety concerns from any brand of Covid-19 vaccines in relation to pregnancy,” he added.
Dr Edward Morris, president of the Royal College of Obstetricians and Gynaecologists, welcomed the updated guidance and stressed it should be a woman’s choice whether to have the vaccine or not “after considering the benefits and risks”.