Corona aktuell: Are the thrombosis cases after vaccination and pill comparable?

Thrombosis cases after vaccination or the pill
Corona aktuell: Can you even compare that?

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The vaccinations with the corona vaccine from AstraZeneca were stopped because there was suspicion that the drug could trigger blood clots in the brain. Thrombosis is a known side effect of birth control pills. But can they even be compared with one another?

AstraZeneca's corona vaccine could have more than just an image problem: After several countries had already stopped vaccinations with the agent in the last week, it was decided last Monday to suspend vaccinations in Germany as well. The reason: Seven people who were vaccinated had blood clots in their brains temporally related to the vaccination – One speaks of so-called sinus vein thrombosis, in which a clot blocks a large cerebral vein.

Women in particular were affected

Noticeable: Six of the people affected were women – but so far there is no explanation for this. In addition, all of these women suffered from platelet deficiency. There was also a medically comparable case of cerebral haemorrhage in a man who was also deficient in blood platelets. According to the Paul Ehrlich Institute (PEI), three of the seven cases were fatal.

Is the pill worse than the vaccination?

Shortly after the vaccination stop, the first posts made the rounds on social media, pointing out that the contraceptive pill can also trigger thrombosis as a side effect. It has been known for years, and what happened: nothing. And in comparison, the risk of developing a blood clot from the pill is actually significantly higher than with the vaccination. However, the cases triggered by the pill are not always dangerous sinus vein thrombosis, but above all the frequent so-called deep vein thrombosis (VTE). Therefore, a comparison of the numbers does not generally make sense. In addition, it is currently being checked whether there is actually a connection between the thrombosis cases and the corona vaccine, while the thrombosis of the pill has already been proven as a possible side effect.

Not all thrombosis is the same …

Sinus vein thrombosis and VTE cannot be compared one-to-one like that mirror reports: A clot in the brain can cause a stroke; in the heart it instead leads to a heart attack. In the vast majority of cases, deep vein thrombosis is less dangerous than sinus vein thrombosis. According to the Federal Institute for Drugs and Medical Devices (Bfarm), VTEs are fatal only "in individual cases".

… and not all pills are the same

In addition, the individual pills also differ from one another. Because only the so-called combination products, which contain both estrogen and progestin, actually increase the risk of deep vein thrombosis. The so-called mini-pill, which contains only progestin, does not increase the risk of a blood clot. And: During pregnancy, the risk of developing a thrombosis is even higher than when taking the pill. In 10,000 deliveries, five to twelve thrombotic embolisms occur in pregnant women, and three to seven cases in the first six weeks after the birth of the child.

A comparison in numbers

Let's compare cerebral vein thrombosis and leg vein thrombosis again directly in numbers:

Cerebral vein thrombosis

Leg vein thrombosis


Hormonal changes (e.g. pregnancy), birth control pills, tumors, hereditary diseases

Hormonal changes (e.g. pregnancy), birth control pills, tumors, hereditary diseases


Paralysis, seizures, headache

Pain and swelling in the affected area on the leg


intensive care

Emergency, treatable if diagnosed early


Consequential damage in 10 percent of cases, another 10 percent die

A pulmonary embolism occurs in 10 to 30 percent of all cases. Every tenth patient of these people dies


0.002 to 0.005 out of 1,000 people annually

About one to two people in 1,000 people annually

EMA continues to rate AstraZeneca as safe

According to the PEI, the number of thrombosis cases after vaccination with AstraZeneca is statistically significantly higher than the number of cerebral vein thromboses that normally occur in the population without vaccination. The European Medicines Agency (EMA) is currently examining the connection more closely. However, she has already made a recommendation for the vaccine to be passed on: The benefits are greater than the risks of the vaccine and it can be described as "effective and safe". However, the experts recommend including the risks of cerebral vein thrombosis, which occurs rarely, in the product information.



German Society for Neurology

Professional Association of German Internists


German Society for Angiology