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About 3% of all pregnant women will give birth to twins, which is an increase in rate of nearly 60% since the early 1980s.
There are more bacteria in your mouth than there are people in the world.
There are approximately 3 million unintended pregnancies in the United States each year.
On average, the stomach produces 2 L of hydrochloric acid per day.
When blood is exposed to air, it clots. Heparin allows the blood to come in direct contact with air without clotting.
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