Claim public are 'lab rats' as Covid-19 vaccine not safe for pregnant women is Mostly False 3

Claim public are ‘lab rats’ as Covid-19 vaccine not safe for pregnant women is Mostly False

The UK Government started its mass Covid-19 inoculation programme this week, with 90-year-old Coventry grandmother Margaret Keenan becoming the first person in the world to receive the vaccine.

Posters on a number of Facebook groups, including Saving Scotland, which has 7,300 members, are highlighting the fact pregnant women have been excluded from the programme to suggest that the vaccine is not safe for use in the general population.

A widely shared post which “was gathered from government websites” states that people are being used as “the lab rats”.

Claim public are 'lab rats' as Covid-19 vaccine not safe for pregnant women is Mostly False 4

Ferret Fact Service looked at the claim and found it Mostly False.


The roll-out of the vaccine, which has been developed by pharmaceuticals giant Pfizer and German biotechnology firm BioNTech, is being managed on a priority basis, following advice given by non-governmental panel the Joint Committee on Vaccination and Immunisation. Part of that advice, which has received significant media attention, is to avoid giving the vaccine to pregnant women because “there are no data as yet on the safety of Covid-19 vaccines in pregnancy, either from human or animal studies”.

It is common for drugs licensed for use in the UK to carry a warning stating that they should not be taken by women who are either pregnant or intending to become pregnant. That is not because those drugs have been found to carry a risk to those women or their unborn children, but rather because they have not been tested on women who are pregnant. 

Many vaccines are safely used by pregnant women, such as flu and whooping cough, but it is standard practice to avoid recommending a new drug until enough evidence has been gathered.

Pregnant women have historically been classed as a vulnerable group so including them in trials was deemed unethical. Without any data to show that a particular drug is safe for use in pregnancy, however, manufacturers must warn that it might not be.

Not everyone is in agreement that pregnant women should be excluded from clinical trials. The concept of vulnerability, which has been the focus of much debate in relation to the Covid-19 vaccine, is in itself a contested issue in the medical world.

In relation to pregnant women, a 2017 study published in the Journal of Medical Ethics found it was “inappropriate and disrespectful” to classify pregnant women as vulnerable because that categorisation “is otherwise applied to populations whose decision-making capacity about research participation is somehow compromised”.

In 2018, the US Food and Drug Administration (FDA) said that as some pregnant women will also have chronic medical conditions that require treatment it could do more harm than good not to allow them to have a particular treatment. It may, therefore, be unethical to exclude them from trials, the FDA said

Regardless of this, the Pfizer/BioNTech trials did not deliberately seek to recruit any pregnant women, so no data exists on how the vaccine might impact on them or their foetuses. Professor Jonathan Van-Tam, the deputy chief medical officer for England, has noted that a number of women who volunteered for the trials have since become pregnant and that if enough data can be gathered from them the guidance may change in future.

How was the Pfizer/BioNTech vaccine tested before being approved? 

All new drugs must go through a series of trials before they can be licensed for use. Although there are usually four phases of trials in humans, the fourth phase is designed to monitor how a drug works in real-life situations after it has been approved for use. That is why fourth-phase trials are also known as post-marketing surveillance trials.

On its own website, Pfizer states that phase 1 trials generally last from between one week to several months; phase 2 trials take up to two years; phase three trials last from between one and four years; and phase 4 trials take at least a year to conclude.

The process was accelerated for the Covid-19 vaccination in view of the unprecedented nature of the pandemic and the pressing need for a medical response. Pfizer and BioNTech, a German biotechnology company, pooled their resources in March with the specific aim of expediting development of the drug.

Dr Richard Hatchett, chief executive officer of the Coalition for Epidemic Preparedness Innovations, said this was achieved by the companies “taking risks with the manufacturing process, but not…with the clinical development”. “They have sped up the development largely by, in parallel, making investments in manufacturing processes that ordinarily you might delay until you had data from your early stage clinical trials,” he said. 

The phase 3 clinical trial of the Pfizer/BioNTech drug ran between July and November and involved 43,000 participants.

Just as the development of the vaccine was expedited, so too was the approval process. The UK Government’s Medicines and Healthcare products Regulatory Agency (MHRA) gave the drug temporary authorisation for emergency use on 2 December after carrying out a so-called rolling review that began in October. Rolling reviews allow the regulator to assess data as they become available rather than waiting for a clinical trial to end. 

As the MHRA has granted temporary rather than full authorisation of the drug it can rescind its approval at any time. It has already made a temporary change to guidance on who should receive the drug after two NHS staff with a history of significant allergies reported adverse reactions. 

Ferret Fact Service Verdict: Mostly False

Pregnant women are not recommended to take the vaccine because they were not included in the clinical trials. It has been thoroughly tested in clinical trials and deemed safe for the public. The vaccine is now in the surveillance stage, where manufacturers observe the general population for any adverse reactions.

This claim is Mostly False

Ferret Fact Service (FFS) is a non-partisan fact checker, and signatory to the International Fact-Checking Network fact-checkers’ code of principles.

All the sources used in our checks are publicly available and the FFS fact-checking methodology can be viewed here.

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Photo thanks to iStock/Udom Pinyo

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