Important phases in a woman's development, namely the first menstruation (menarche) and menopause, are natural events that are influenced by hormonal dynamics as well as genetic and environmental factors. Menarche marks the beginning of a woman's reproductive abilities, while menopause marks the end. Both of these events have varying mean ages across populations, and knowledge of these physiological changes is critical in the context of reproductive health.
When Do Women Have Their First Menstruation?
Usually, the normal age to experience menarche or first menstruation is around 1-2 years after a girl starts experiencing signs of puberty. Before experiencing their first menstruation, women will experience various changes as they enter adolescence towards maturity. These changes include height gain, breast development, and hair growth in the pubic and axillary areas.
Generally, the age range for menstruation in girls is between 10-14 years. According to information from the Journal of Reproductive Health, in Indonesia, the average age of first menstruation in girls is around 12.96 years.
When a girl has menstruation, this indicates that she already has the ability to get pregnant. In fact, pregnancy can occur even before the first menstruation appears. This is caused by the activity of hormones that support the pregnancy process that is already active in a woman's body.
These hormones are estrogen and progesterone, which play an important role in the formation of the lining of the uterus. Both of these hormones are produced by the ovaries, organs that also produce eggs or ova.
When the uterine lining thickens, the egg is ready to be fertilized. If no fertilization occurs, the uterine lining along with the blood sheds, resulting in menstruation. Conversely, if a girl engages in sexual intercourse and the egg is fertilized by sperm, the ovum will attach to the lining of the uterus, and the process of pregnancy will begin, from the formation of a zygote to becoming a fetus.
Average Age of Menopause in Women
Menopause refers to the phase when a woman stops menstruating and is no longer able to get pregnant naturally. Menstruation involves the shedding of the uterine lining in the absence of fertilization of an egg. The menstrual cycle usually occurs once a month and lasts 7-14 days. Menopause is a normal stage in a woman's life, generally occurring between the ages of 45 and 55.
When you reach menopause, the frequency of menstruation will decrease or even stop completely. This is triggered by a decrease in the level of the hormone estrogen in a woman's body. In the UK, the average age for women to go through menopause is 51. However, it is estimated that 1 in 100 women experience menopause before the age of 40. This condition is known as premature menopause or premature ovarian insufficiency.