The menstrual cycle is a monthly series of changes that the female body goes through in preparation for the possibility of pregnancy. It typically lasts around 28 days, although it can range from 21 to 35 days in different individuals. The cycle is controlled by hormones and involves several key phases:
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Menstrual Phase: This is the beginning of the cycle, where the uterus sheds its lining if no fertilization has occurred. This results in menstrual bleeding, which usually lasts from 3 to 7 days.
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Follicular Phase: After menstruation, the body starts to prepare for a new cycle. Follicle-stimulating hormone (FSH) stimulates the growth of follicles in the ovaries. Each follicle contains an egg, and as they mature, they produce estrogen, which helps to rebuild the uterine lining.
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Ovulation: Around the midpoint of the cycle, a surge in luteinizing hormone (LH) triggers the release of a mature egg from one of the ovaries. This is the most fertile time in the cycle, and the egg can be fertilized by sperm.
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Luteal Phase: After ovulation, the empty follicle transforms into the corpus luteum, which produces progesterone. This hormone helps to thicken and maintain the uterine lining in preparation for a potential pregnancy. If the egg is not fertilized, the corpus luteum disintegrates, leading to a drop in progesterone levels.
If there is no pregnancy, the cycle starts anew with the menstrual phase as the uterine lining is shed.
The menstrual cycle can be influenced by various factors, including hormonal imbalances, stress, diet, and overall health. Regular cycles are an important aspect of reproductive health.