Women who are pregnant, taking the pill, or taking estrogen may be at high risk of fatal blood clots if they get coronavirus, doctors warn
- High estrogen levels due to pregnancy, the use of oral contraceptives or hormone replacement therapy increase the risk of blood clots
- Coronavirus attacks blood vessels and can cause clots that eventually kill many patients – even young and otherwise healthy ones
- Doctors warned in an Endocrine Society manuscript that women may consider staying on the pill or taking aspirin during the pandemic
Women with birth control may be at increased risk of blood clots if they get coronavirus, a new study warns.
COVID-19 increases the risk of blood clots for those using oral contraceptives, according to the study published Wednesday.
Birth control pills contain estrogen that can narrow the blood vessels. People who are pregnant or taking HRT (hormone replacement therapy) are at the same risk.
Prescribing blood thinners – such as aspirin – to protect all three groups, suggested co-author Dr. Daniel Spratt.
“During this pandemic, we need additional research to determine whether women who become infected during pregnancy should receive anticoagulant therapy – or whether women on birth control pills or hormone replacement therapy should discontinue it,” he said.
Women who use birth control are already at increased risk of blood clots due to estrogen in the pill, and doctors warn that they are at special risk if they receive coronavirus that can also cause clots (resistant)
Coronavirus can cause blood clots – even in previously healthy people, said Dr. Spratt.
In addition, estrogen nourishes potentially deadly deep vein thrombosis in some future mothers – and in women who take the pill or HRT.
The blockages usually start in the legs. They can go up and cause a heart attack or stroke.
Oral contraceptives are known to carry a small risk of the condition – which may be compounded by the coronavirus, the new study in endocrinology reports.
“If infected with Covid-19, the risk of blood clotting in these women could be even higher,” the study authors wrote.
Dr Spratt, of the Maine Medical Center in Portland, said, “Research that helps us understand how the coronavirus causes blood clots may also provide us with new knowledge about how they form in other environments and how they can be prevented.”
The connections between blood clots and COVID-19 – including the effects of estrogen therapy or pregnancy – are complicated.
Dr. Spratt said several studies using innovative animal and tissue models will be needed to shed light on it.
Birth control pills remain the most popular birth control method in the UK and the second most popular form in the US, despite alternatives such as injections and implants.
More than nine million American women take them at the same time, despite possible side effects ranging from depression to weight gain.
They also involve a fourfold increase in a woman’s chance of developing a blood clot.
Most of them contain estrogen and a synthetic form of progesterone. These are the hormones that support pregnancy and, by imitating the condition, prevent it.
But they also increase clotting factors. For the average woman, the absolute risk of a blood clot is only one in a thousand. The coronavirus can significantly increase this.
“As more information emerges regarding the effects of Covid-19, the question arises whether infection exacerbates the blood clots and strokes associated with combined oral contraceptives and other estrogen therapies, as well as the pregnancy-related risk,” said Dr. Spratt.
The number of strokes doubles from about four to eight out of 100,000 young women per year. Similar figures have been found for older women on HRT.
During pregnancy, the risk of blood clots quadrupled. The mechanisms for this and the duration of effect after discontinuation of therapy remain unclear, ” said Dr. Spratt.
“A general recommendation is to discontinue estrogen-containing preparations two weeks before planned activities that may cause thrombosis, such as surgery or long flights.”
He added, “Conversations between clinicians, researchers, endocrinologists, and hemotologists are needed to investigate possible interactions between Covid-19 and pregnancy or estrogen therapy that could direct management.”