Fertility and Menstruation

The woman's gender-equal development

The woman's genitalia comprised of the external genitalia with venus mountain, labia and Clitorial and vagina opening. The internal reproductive organs include the vagina (vagina), womb (uterus), fallopian tubes (salpinges) and ovaries (ovaries). The ovary called the primary reproductive organs (gonads), which is the female to the Independent's testicles. Her eggs are formed. Newborn girl is already formed all the eggs in her ovaries still immature.

When the girl grows, there will at some point be an increase in production of female hormones, and the girl will go into puberty, and develop female characteristics, ie. kritelvævet in the breasts grow, she will be starting kønsbehåring, fat begins to change, and she will at some point get its first menstruation (menarche). All these changes are caused by complex interactions of hormones, whose full context is not yet known.

Hormonal systems involved in the development and fertility

The best known endocrine systems that regulate female fertility (including menstruation), is the balance betweenGnRH(released from the hypothalamus in the brain),LH / FSH(released from the pituitary gland in the brain) andestrogen / progesteroneWhich are primarily released from the ovary.
GnRH stands for Gonadotropin Releasing Hormone, which means that it is the hormone that provides for the secretion of gonadotropins, which is LH and FSH.

LH stands for luteinizing hormone and FSH for folikelstimulerende hormone. These two hormones increase the excretion of the female hormones estrogen and progesterone, and is responsible for maturation of eggs and ovulation.

FSH and LH inhibits secretion of GnRH. Estrogen and progesterone inhibits the secretion of both GnRH and FSH / LH. Thus kept hormone levels through the menstrual cycle in check.

Puberty, ovulation and menstrual cycle

When the girl when her puff beginning, the hypothalamus begins to separate GnRH, and the endocrine system in momentum, so that, inter alia, estrogen levels rise. This is primarily the reason for the development of the female sexual characteristics.

After a short exposure to estrogen (usually about 2 years) will experience a girl's first menstrual period. The first contraction is usually something irregular, but eventually there will be a fairly regular menstrual cycle, the average 28 days, of which about. 5 days is menstruation, that is bleeding. A menstrual cycle is starting at first blødningsdag and it ends at the next period, the first bleeding.

FSH stimulates the ovaries to develop a primary folikel, a small bladder in egg stick, which, in addition to the egg, containing some cells, which produce estrogen. Around the middle of the menstrual cycle dashed this folikel, and the egg is released (ovulation / ovulation). Egg picked up by some Cilium on eggshells leaders and transported to the uterus, which would take several days. The folikel, which contained egg, which is now dotted, coincide, and form the yellow body (corpus luteum). This produces both estrogen and progesterone.

Estrogen has, while foliklen mature, received the innermost layer of the uterus (endometrium) to grow. After ovulation, which also found progesterone in the blood, the endometrium will grow even more, and glands it will isolate any mucus that makes it easy for any one. fertilized eggs that become lodged.

Slimy in the cervix are at the beginning of the cycle when there is only the influence of estrogen, be easy to pass the sperm. After ovulation, the increased amount of progesterone get slimy in the cervix to change the composition and make it difficult for sperm to penetrate. This is one of the reasons that the optimum time for fertilization is from about. 4 days before ovulation to one day after.

Hormone Effect during ovulation and menstruation

In the above sketch Hormones are the context outlined. Hypothalamus releasing GnRH, which stimulates the pituitary gland to excrete FSH, which stimulates the development of a primary folikel. A few days before ovulation, there is an ædring of estrogen effect on the secretion of FSH and LH. From that inhibit the secretion stimulated it now instead, and therefore increases the levels of FSH and LH. This increase will have to foliklen burst, and there is ovulating. The burst folikel develops the yellow body, which pro

This rapid drop in estrogen and progesterone levels will have a uterus lining to go to the land, and it would therefore be eliminated as blood and vævsrester, which marks the first day of contraction.

Insemination

If the egg is fertilized on its way to the uterus of the egg head, it will become lodged in the uterus lining, which then formed a few cells, which excrete the hormone hCG. This will in the first trimester of pregnancy maintain the function of the yellow body, and thus estrogen and progesterone production. Later the placenta would take over production of estrogen and progesterone, so that livmoderslimhinden not going to land. hCG is the hormone that is measured on taking a pregnancy test.

Transition Age

When the woman approaching menopause, her ovaries will be worse because of aging to form folikler and thus estrogen. So stop ovulating, and the woman may begin to experience the symptoms that follow menopause.

Contraceptive pill

Contraceptive pill containing artificial estrogen and progesterone. These two hormones have in this context to function to keep the levels of FSH and LH down, which can not be a maturation of a folikel and thus an ovulating. Progesterone has previously mentioned also an effect on mucus in the cervix, thus making it difficult for sperm to reach the uterus.

Estrogen and progesterone in the pill also livmoderslimhinden to stimulate growth. When the woman is on hiatus with the pill, mucous membranes will also go to the grounds, and the woman have a menstrual-like bleeding.