The levels of female hormones change drastically with age. Hormones are usually present at birth, increase in puberty and pregnancy, and then decline as women approach menopause. The results of reduced hormone levels include both infertility and unpleasant symptoms such as hot flashes and headaches. Thus, many aging women try to replace fading hormones with produced substitutes for estrogen and progesterone, which can also be used in various forms to prevent pregnancy during the fertile years.
Female hormones are present from birth, causing some babies – male or female – to have breast enlargement during childhood. This may be a result of estrogen passing from mother to child via the placenta, or it may be caused by the child’s own body making prolactin in response to the sudden drop of estrogen from the body when the umbilical cord is cut. Some baby girls experience the occasional breast enlargement of the first couple of years of life, showing that hormones affect their lives early.
At puberty, the hypothalamus produces gonadotropin-releasing hormone, which in turn signals to the pituitary gland to release extra hormones. These include luteinizing hormone (LH) and follicle stimulating hormone (FSH), both of which stimulate the ovaries to make more hormones. The most well-known female hormones produced by the ovaries are estrogen and progesterone, which assist LH and FSH in regulating the menstrual cycle. These hormones raise the levels of estrogen just before ovulation, and then raise the level of progesterone for about two weeks afterwards. When it is not released the egg does not fertilize, progesterone levels decrease, which causes the uterine lining to begin to fold in what is called menstruation.
Pregnancy and female hormones go hand in hand, as a lack of a common drop in progesterone does not occur when a woman becomes pregnant, which is why menstruation never shows up during this cycle. Instead of human chorionic gonadotropin (hCG) signals to the ovaries earn more progesterone and estrogen, though the placenta usually takes over this position just before the second trimester. The results of higher levels of these hormones are increased blood supply, a thicker uterine lining, and uterine muscles that are relaxed enough to grow with the unborn baby. While prolactin increases to make breast milk just before the birth of the baby, both estrogen and progesterone levels suddenly drop after birth, sometimes resulting in birth depression. These female hormones begin to decrease even more as menopause approaches.
Declining levels of estrogen during menopause can result in problems for the bone and the heart, such as osteoporosis and heart disease. Night sweats, hot flashes and vaginal dryness are also common symptoms of a loss of this sex hormone. Headaches and fatigue can occur, too, leading to menopausal discomfort. On the other hand, lower levels of progesterone lead to infertility, vaginal dryness and low libido. Weight gain, depression and bloating are all additional consequences of the reduced levels of progesterone that come with menopause.
For these reasons, hormone replacement therapy (HRT) is often used by aging women who dislike the effects of lower levels of female hormones. HRT usually comes as a pill or patch to be placed on the body, and it can reduce symptoms such as hot flashes and night sweats. Before menopause, some women use synthetic hormones to prevent pregnancy, because excess estrogen in many types of birth control can prevent ovulation. Progesterone which comes in many forms of birth control can thicken the mucus in the cervix to make it difficult for sperm to get to the cervix, and it can also make the uterine lining too thin for an embryo for the implant.
- Progesterone contains oral contraceptives thicker mucus in the cervix and thin cervical mucosa.
- Age is the most common cause of reduced libido.
- Postpartum depression may be caused by a decrease in progesterone levels after birth.
- A common symptom of changing estrogen hormone levels and menopause is hot flashes.
- During menopause, a woman’s levels of estrogen, progesterone and testosterone plummet.