A young woman's menstrual cycle brought tears to her eyes. But unlike most period-related tears, hers were bright-red tears of blood.
When the 25-year-old visited an emergency room with bloody tears oozing from both eyes, it was her second such episode in the past two months, doctors recently reported. Blood tears are a rare condition known as haemolacria, which can have different causes. In the woman's case, her eyes were otherwise normal and she wasn't ill or injured. However, both instances of bloody tears coincided with the onset of her period, the physicians wrote in a case report.
Normal menstruation can sometimes trigger cyclical bleeding outside the uterus, known as vicarious menstruation. The woman's crimson teardrops likely represented a highly unusual convergence of two conditions — vicarious menstruation and haemolacria — leading to period-triggered tears of blood, according to the report.
Though the woman's crimson tears looked alarming, when the doctors examined her they found that her eyes were undamaged and the blood tears weren't accompanied by headaches, dizziness or other symptoms of a health problem. Nor were there any signs of abnormality in her sinuses, tear ducts or in the bloody tears themselves, the researchers wrote in the March issue of the journal BMJ Case Reports.
Common causes of haemolacria include inflammation, trauma, lesions, tumors, hypertension, diseases such as jaundice and anemia, and vascular disorders, according to a report published on Feb. 14 by the National Center for Biotechnology Information. But after ruling out these possible causes of the woman's blood tears, the doctors identified the source as vicarious menstruation, which can cause bleeding from the nose, ears, lungs, nipples, intestines "and even skin," as well as from the eyes, the doctors wrote.
Indeed, the woman said that she had also experienced a nosebleed the first time she cried blood.
Certain types of eye tissue are known to be affected by hormonal changes; for example, the cornea's curve and thickness can vary "during different phases of menstrual period, pregnancy and lactation," which could explain why the woman's menstruation triggered bleeding from her eyes, according to the report. The doctors treated her with oral contraceptives, and after three months of hormonal therapy, the woman experienced no additional bleeding incidents.
"This is a rare and unusual clinical case," the doctors wrote, adding that there was nothing like it described in any recent scientific literature. However, more research would be required in order to understand exactly what caused the woman's bloody tears, and to determine how such a condition could be effectively managed long-term, the researchers concluded.
Originally published on Live Science.
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Mindy Weisberger is an editor at Scholastic and a former Live Science channel editor and senior writer. She has reported on general science, covering climate change, paleontology, biology, and space. Mindy studied film at Columbia University; prior to Live Science she produced, wrote and directed media for the American Museum of Natural History in New York City. Her videos about dinosaurs, astrophysics, biodiversity and evolution appear in museums and science centers worldwide, earning awards such as the CINE Golden Eagle and the Communicator Award of Excellence. Her writing has also appeared in Scientific American, The Washington Post and How It Works Magazine.