Women need more information about contraceptive options, experts said, after concerns over rare blood clots linked to the AstraZeneca Covid jab prompted a debate over side-effects caused by certain forms of the pill.
On Wednesday the UK’s Medicines and Healthcare products Regulatory Agency (MHRA) said that evidence that the jab could be causing a rare blood clotting syndrome was growing stronger. As a result the UK’s Joint Committee on Vaccination and Immunisation (JCVI) recommended that healthy people under the age of 30 who were at low risk of Covid should be offered a different vaccine if possible.
But the announcement prompted numerous posts on social media questioning why there had been little comment on combined hormonal contraceptives.
These methods, which include certain pills, vaginal rings and patches, contain forms of oestrogen and progesterone hormones and have been associated with increased risk of clots, including deep vein thrombosis, pulmonary embolism and cerebral venous sinus thrombosis (CVST) – a very rare clot on the brain.
Speaking on ITV’s Good Morning Britain Adam Finn, a professor who is part of the JCVI, confirmed the difference in risk.
“The risks of thrombosis that come with taking the pill are very much higher than the risks that we were just seeing on those slides [relating to the rare blood clots from the AstraZeneca vaccine],” he said.
According to a 2014 report by the European Medicines Agency the risk of venous blood clots overall is from five to 12 cases per 10,000 women who take combined hormonal contraceptives for a year, compared with two cases a year per 10,000 women not using such contraceptives.
The concerns around the Oxford/AstraZeneca vaccine focus on a specific blood clotting syndrome, including cases of CVST with low platelets. The latest MHRA figures suggest the rate for the blood clotting syndrome is about four cases per million vaccinated people. This figure is not specific to women of reproductive age.
Sexual health experts have stressed the need for improved access to information on contraceptive options.
Jonathan Lord, MSI Reproductive Choices’ UK medical director, said: “The combined oral contraceptive pill is not suitable for all. For anyone with higher risk factors there are alternative oral contraceptives which give no increased clotting risk and suit most very well.”
According to NHS advice women should not take combined hormonal contraceptives if they are over 35 and smoke, or have certain medical conditions.
“The essential element is that contraception and quality advice are readily available,” Lord said. “Being able to access this – and having the really effective and convenient long-acting reversible methods available without a long wait – is where the priority should lie.”
On Thursday the clinical effectiveness unity of the Faculty of Sexual and Reproductive Health (FSRH) released guidance noting it was not clear whether the risk of the rare clotting syndrome linked to the AstraZeneca jab could be affected by use of combined hormonal contraceptives. But the unit recommended users of such contraception did not stop using it when their got their first or second Covid-19 vaccine.
Experts have also stressed that the risk of blood clots among those using combined hormonal contraceptives remained low. They said women should not suddenly abandon their contraception, not least as there was a far larger risk of blood clots during and after pregnancy.
Clare Murphy, chief executive of the British Pregnancy Advisory Service, said: “It is vitally important that discussions comparing the risks of blood clots associated with the AstraZeneca Covid-19 vaccine with those [associated with] the contraceptive pill do not pave the way to a repeat of the 1995 pill scare, which led to a significant increase in unplanned pregnancies.”
Diana Mansour, vice president of the FSRH, said there were a number of reasons – such as helping to control periods and clearing up acne – why women might choose to use combined hormonal contraceptives. While there are many contraceptives, such as pills, and implants containing only synthetic progesterone, which do not increase the risk of blood clots, these had other advantages and disadvantages.
However, a report published in 2020 revealed that women in England were struggling to get contraception, a situation made worse by the pandemic, with problems including long waiting times and a lack of GPs trained to fit long-acting reversible contraceptives such as the implant. The inquiry said such problems also affected trans men and non-binary individuals.
Cynthia Graham, professor in sexual and reproductive health at the University of Southampton, said that while some women asked for the combined pill, in other cases that might be the only contraception offered to them by healthcare providers besides condoms.
Both Graham and Mansour said combined hormonal contraceptives should remain on offer. But they backed calls for greater access to consultations about different forms of contraception.
“Not one method suits every person,” said Mansour. “It is personal choice.”
