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Approximately 500,000 babies are born each year in the United States to teenage mothers.
Normal urine is sterile. It contains fluids, salts, and waste products. It is free of bacteria, viruses, and fungi.
The first-known contraceptive was crocodile dung, used in Egypt in 2000 BC. Condoms were also reportedly used, made of animal bladders or intestines.
In 1864, the first barbiturate (barbituric acid) was synthesized.
There are more bacteria in your mouth than there are people in the world.
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