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There are 60,000 miles of blood vessels in every adult human.
In the United States, there is a birth every 8 seconds, according to the U.S. Census Bureau's Population Clock.
No drugs are available to relieve parathyroid disease. Parathyroid disease is caused by a parathyroid tumor, and it needs to be removed by surgery.
Sperm cells are so tiny that 400 to 500 million (400,000,000–500,000,000) of them fit onto 1 tsp.
There are approximately 3 million unintended pregnancies in the United States each year.
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