Hormone Changes in Womenby Kay Dean
The process of growing from infancy to girlhood, young adulthood and old age is significantly impacted by both the presence and absence of natural hormones. A woman's hormones tell her body when to enter puberty, when to prepare for and feed a baby and when the child-bearing years should cease. Hormones regulate her monthly periods and influence her moods, sex drive and complexion. They are also linked to significant diseases such as breast cancer, osteoporosis and heart disease.
Infants, both boys and girls, are exposed to hormones from their mother that pass through the placenta during the final few weeks of pregnancy. Estrogen can cause the breasts of infants to swell. Infants who are breastfed may continue to experience enlarged breasts and may even secrete a milk-like fluid from their nipples. Maternal hormones passed to infants during pregnancy and through breastfeeding may contribute to mild skin conditions such as baby acne or breast-milk jaundice. None of these conditions is considered abnormal or poses,m a risk to the infant's health.
Girls typically enter puberty sometime between the ages of 8 and 13. Gonadotropin-releasing hormone, or GnRH, prompts the pituitary gland to release luteinizing hormone (LH) and follicle-stimulating hormone (FSH) into the bloodstream. These hormones prompt the ovaries to produce the female hormone, estrogen. The body's reaction to the release of all these hormones include rapid growth, weight gain, the development of the breasts, the growth of hair under the arms and in the pubic region, and the beginning of menstruation.
LH and FSH hormones that are released at the onset of puberty stimulate the production of the female hormone estrogen. Estrogen aids in the maturation process. Girls typically get their first menstrual period around two years after the onset of puberty. The menstrual cycle is regulated by a combination of increasing and diminishing hormones and typically lasts around 28 days. Every woman is different, so a normal cycle may range from 21 to 35 days, according to the National Women's Health Information Center. Hormone levels rise during the first half of the cycle leading up to ovulation to prepare the body for a potential pregnancy. If that pregnancy does not occur, hormone levels will drop, allowing the uterus to shed its lining, which is discharged during the monthly period, which lasts approximately three to five days.
Female hormones play an important role in a woman's everyday life. LH, FSH, estrogen and another female hormone called progesterone help regulate the menstrual cycle by determining when ovulation will occur. The ovaries also produce small amounts of the male hormone testosterone, which is important for building muscle tissue and bone mass. Hormones are responsible for determining there fat is distributed on the body, typically the hips, buttocks, breasts and thighs, resulting in a woman's curvy appearance.
The levels of female hormones typically increase during the time frame leading up to and including ovulation. If the egg does not become fertilized, the hormone levels drop, allowing the uterus to shed its lining, resulting in the monthly period. If the egg is fertilized, the levels of estrogen and progesterone remain high to prepare the uterus for implantation, and a new hormone, human chorionic gonadotrophin (HCG) is produced. These hormones thicken the uterine lining, stimulate the production of breast milk and increase blood flow throughout the body.
The levels of the female hormones estrogen and progesterone decline as the ovaries' supply of eggs nears exhaustion. This results in the perimenopause, the period of time leading up to menopause. Perimenopause is marked by numerous hormone-induced side effects, many of which are unpleasant, including night sweats, heat flashes, mood swings, vaginal dryness and irregular periods. Perimenopause affects women differently and may last from a few months to several years.
Once a woman's supply of eggs is completely exhausted, her monthly period stops and she is no longer able to conceive children. This time period is called menopause, and generally occurs when she is in her late forties to early fifties, with the average age in the U.S. being 51 as of 2009, according to MayoClinic.com. Menopause is marked as having occurred 12 months after the final menstrual period. After menopause, estrogen levels are reduced to about 10 percent of pre-menopausal levels. This reduction in estrogen can result in symptoms such as night sweats, hot flashes, vaginal dryness and contribute to long-term conditions including osteoporosis and heart disease. Symptoms can be treated with hormone replacement therapy (HRT) or postmenopausal hormone therapy (PHT), but such organizations as the American Heart Association do not recommend such therapies, due to their increased risk of breast cancer and cardiovascular diseases. Natural alternatives to reduce menopausal symptoms include herbal-based remedies.
- MedlinePlus: Aging Changes in the Female Reproductive System
- TeensHealth: Everything You Wanted to Know About Puberty
- MayoClinic.com: Menopause
- American Pregnancy Association: Human Chorionic Gonadotropin (hCG): The Pregnancy Hormone
- Medicine Online: Normal Conditions in a Newborn Resulting From Maternal Hormones
- American Heart Association: Menopause and the Risk of Heart Disease and Stroke
- Jupiterimages/Comstock/Getty Images