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Sperm cells are so tiny that 400 to 500 million (400,000,000–500,000,000) of them fit onto 1 tsp.
Pregnant women usually experience a heightened sense of smell beginning late in the first trimester. Some experts call this the body's way of protecting a pregnant woman from foods that are unsafe for the fetus.
Fewer than 10% of babies are born on their exact due dates, 50% are born within 1 week of the due date, and 90% are born within 2 weeks of the date.
Tobacco depletes the body of vitamins A, C, and E, which can result in any of the following: dry hair, dry skin, dry eyes, poor growth, night blindness, abscesses, insomnia, fatigue, reproductive system problems, sinusitis, pneumonia, frequent respiratory problems, skin disorders, weight loss, rickets, osteomalacia, nervousness, muscle spasms, leg cramps, extremity numbness, bone malformations, decayed teeth, difficulty in walking, irritability, restlessness, profuse sweating, increased uric acid (gout), joint damage, damaged red blood cells, destruction of nerves, infertility, miscarriage, and many types of cancer.
The most destructive flu epidemic of all times in recorded history occurred in 1918, with approximately 20 million deaths worldwide.
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