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In 1844, Charles Goodyear obtained the first patent for a rubber condom.
Pubic lice (crabs) are usually spread through sexual contact. You cannot catch them by using a public toilet.
The average adult has about 21 square feet of skin.
Thyroid conditions may make getting pregnant impossible.
Cancer has been around as long as humankind, but only in the second half of the twentieth century did the number of cancer cases explode.
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