Experts warn against comparing AstraZeneca vaccine risks to contraceptive pill

A ‘pill scare’ in 1995 led to a rise in unplanned pregnancies

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As scientists work to better understand the potential link between the AstraZeneca coronavirus vaccine and extremely rare blood clots, the British Pregnancy Advisory Service (BPAS) is warning against comparing the risk factors against taking the contraceptive pill.

Over 18 million doses of the AstraZeneca vaccine have so far been administered across Europe. Among them, 30 thromboembolic events, which refers to the formation of a blood clot, have been recorded - seven of which were fatal.

Concerns over its safety have led some European and North American countries to suspend the use of the Oxford vaccine among certain age groups, despite the risk of developing a blood clot being incredibly low at 0.000095 per cent.

The Medicines and Healthcare products Regulatory Agency (MHRA) stress that the vaccine is safe to use as any risks are outweighed by the risks from Covid-19.

In response to the news that the vaccine has stopped trials in children and teens and will not be given to under 30s when eligible, many women have taken to Twitter to highlight that the risk of blood clotting with the contraceptive pill is 0.1 per cent.

But, in a thread posted on their Twitter account, the BPAS has expressed concern that comparing risk factors of the vaccine with the contraceptive pill may lead to women stopping taking it in a similar “pill scare” that occurred in 1995.

During that time, many women switched brands or stopped taking the pill altogether because of fears over the risk of deep vein thrombosis. It led to a rise in unplanned pregnancies and a 9% increase in abortions.

They said: “We are concerned that discussions comparing the risks of blood clots associated with the AstraZeneca vaccine with those of the contraceptive pill could pave the way to a repeat of the 1995 “Pill Scare” which led to a significant increase in unplanned pregnancies.”

The BPAS confirmed that the pill is safe to take. There is only a small risk of venous thrombosis while taking it and the risk of venous thrombosis during pregnancy is, in fact, higher, they clarified.

They continued: “Combined hormonal contraceptives (CHC) are overall very safe for most women to take - the very small increased risk of venous thrombosis (VTE) with use of the combined pill is far lower than the risk for VTE during or after pregnancy.”

A review of the risks of the combined contraceptive pill was undertaken in 2014 by the MHRA. It confirmed, “the benefits of any combined hormonal contraceptive far outweigh the risk of serious side effects”.

The BPAS reiterated that discussion around the safety of the AstraZeneca vaccine should not harm trust in the contraceptive pill.

They wrote: “Rightly reassuring the public about the safety of the AstraZeneca vaccine must not come at the expense of trust in the most commonly used contraceptive method in the UK.”