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Pubic lice (crabs) are usually spread through sexual contact. You cannot catch them by using a public toilet.
Most childhood vaccines are 90–99% effective in preventing disease. Side effects are rarely serious.
Thyroid conditions may make getting pregnant impossible.
The people with the highest levels of LDL are Mexican American males and non-Hispanic black females.
Sperm cells are so tiny that 400 to 500 million (400,000,000–500,000,000) of them fit onto 1 tsp.
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