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Approximately 15–25% of recognized pregnancies end in miscarriage. However, many miscarriages often occur before a woman even knows she is pregnant.
About 3% of all pregnant women will give birth to twins, which is an increase in rate of nearly 60% since the early 1980s.
In 1864, the first barbiturate (barbituric acid) was synthesized.
The familiar sounds of your heart are made by the heart's valves as they open and close.
Cyanide works by making the human body unable to use oxygen.
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