On Monday, Dr Viki Male, reproductive immunology expert at Imperial College London, told Sky News that "from an evidence point of view ... our advice [is that] the right time to get vaccinated is as soon as you can."

"The evidence says that it doesn't make any difference to the safety or efficacy of the vaccine… so today, today is the best day [to get the vaccine]," she added.

Male said that, while concerns about protecting babies are valid and especially so during the first trimester, women should not wait until their 12- or 20-week scan to get the vaccine, as anecdotal reports suggest many are doing.

GP David Lloyd also weighed in, explaining that that the demographic is a particularly high-risk group. "Women's immune systems when they're pregnant are very different from when they're not pregnant", he said, reiterating that it is "so, so safe and so important" for them to complete the vaccination course.

The renewed calls for gestating mothers to get inoculated comes after new data from NHS England showed that between July 1 and September 30, 17% of Covid patients requiring a special lung machine were pregnant women who had not had at least one shot of a coronavirus vaccine.

Statistics also showed that, out of all women in intensive care aged between 16 and 49, almost a third (32%) were pregnant women on extracorporeal membrane oxygenation (ECMO) – equipment used when a patient's lungs are so damaged by the virus that a ventilator cannot maintain oxygen levels.The figure has increased by 6% since the outbreak of the pandemic.

Health and Social Care Secretary Sajid Javid welcomed the data indicating that over 81,000 pregnant women had received their first dose of a Covid vaccine, while 65,000 are double-jabbed, but said "more needs to be done."