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There are 60,000 miles of blood vessels in every adult human.
Thyroid conditions may make getting pregnant impossible.
Today, nearly 8 out of 10 pregnant women living with HIV (about 1.1 million), receive antiretrovirals.
Sperm cells are so tiny that 400 to 500 million (400,000,000–500,000,000) of them fit onto 1 tsp.
People about to have surgery must tell their health care providers about all supplements they take.
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