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In the United States, there is a birth every 8 seconds, according to the U.S. Census Bureau's Population Clock.
The first-known contraceptive was crocodile dung, used in Egypt in 2000 BC. Condoms were also reportedly used, made of animal bladders or intestines.
Pubic lice (crabs) are usually spread through sexual contact. You cannot catch them by using a public toilet.
There are over 65,000 known species of protozoa. About 10,000 species are parasitic.
Medication errors are more common among seriously ill patients than with those with minor conditions.
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