Female sex hormones such as progesterone and estrogen are produced in the ovaries. Ovarian hormone secretion is influenced by numerous factors, not the least of which are the levels of hormones produced by the pituitary gland, known as follicle stimulating hormone, or FSH and luteinizing hormone, or LH. Gary Thibodeau, PhD, author of the book, "Anatomy & Physiology," explains that these pituitary hormones also induce important reactions in the female body related to monthly reproductive cycles.
Estrogen
Estrogen is one of two ovarian hormones that control the development of the breasts during puberty. This occurs due to estrogen's stimulating effects on the ducts of the mammary glands. Thibodeau notes that breast size is a result of the amount of fat surrounding the gland and has no relation to the functional ability of the breast. Estrogen also prepares the mammary glands for the development of secretory cells, which occurs in response to progesterone levels. Estrogen encourages the lining of the uterus to thicken prior to ovulation.
There are a number of different forms of estrogen circulating in a woman's body. Estradiol is the most important of these, according to MedlinePlus. In addition to breast development, it encourages the growth of the uterus, Fallopian tubes and vagina.
Progesterone
Working in concert with estrogen, progesterone stimulates the growth of the secretory cells of the mammary glands, which are called alveoli, and contributes to the growth of breasts during puberty and pregnancy. It is also essential in maintaining the monthly cycle of ovulation and menstruation, according to Drugs.com. Progesterone prompts the uterine lining to mature in anticipation of implantation of a fertilized egg.
Follicle Stimulating Hormone
FSH is released by the adenohypophysis, the anterior portion of the pituitary gland. It is produced in conjunction with the regular monthly cycle of ovulation, where it causes ovarian follicles to develop and secrete estrogens. MedlinePlus attributes FSH with the ability to stimulate egg production and estradiol secretion in women, while in men is stimulates sperm production.
Luteinizing Hormone
LH and FSH work synergistically to encourage the development of ovarian follicles and the secretion of estrogen. A surge in LH is thought to prompt ovulation, thus LH is the primary hormone of interest in home pregnancy test. A study conducted by researchers in the endocrinology department at the University Hospital of Brazil and published in the New England Journal of Medicine found that a deficiency in LH was linked to hypogonadism, or immature development of the sexual organs, in both men and women.
References
- Anatomy & Physiology, 5th Edition; Gary Thibodeau, PhD and Kevin Patton, PhD; 2003;
- MedlinePlus: Estradiol Test
- Drugs.com: Progesterone
- New England Journal of Medicine; "Luteinizing Hormone Beta Mutation and Hypogonadism in Men and Women"; Lofrano-Porto A, et al; August 2007
- MedlinePlus: FSH
