Rhythm method
Also known as fertility awareness, natural family planning, and periodic abstinence, this approach to contraception entails not having sexual intercourse on the days of a woman’s menstrual cycle when she could become pregnant or using a barrier method (such as a condom, the diaphragm or a cervical cap) for birth control on those days.
Because a sperm may live in the female’s reproductive tract for up to 7 days and the egg remains fertile for about 24 hours, a woman can get pregnant within a substantial window of time — from 7 days before ovulation to 3 days after. Methods to approximate when a woman is fertile are usually based on the menstrual cycle, changes in cervical mucus, or changes in body temperature.
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The structure formed by the thoracic vertebrae and ribs, the sternum (breastbone), and the costal cartilages (that attach the ribs to the sternum). A cage is an enclosure made of “open work” that usually houses animals. The rib cage was thought to resemble an animal cage (although the largest “animals” it holds are the heart […]
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An extra rib that arises from the seventh cervical vertebra. It is located above the normal first rib. A cervical rib is present in only about 1 in 200 people. It may cause pinching of nearby nerves or arteries, in which case it sometimes is removed surgically.
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