Fertility

As fertility (also: fertility ), the ability of animals and plants designated to produce offspring ( "fruits" ). Fertility is the opposite of infertility.

Definitions

The terms fertility and fertility as well as derived variants are used in different contexts:

• As fruits in the strict sense, the flowers of plants are referred to in the state of seed maturation in botany; in a broader sense the term is but transferred to other multi-cellular organisms. In earlier usage, therefore, was the word " fetus " is the term for a human embryo or fetus. In medicine and biology, the synonym fertility is ( = fertile, productive, fruitful from the Latin fertilis ) used in relation to man.
• Fekundabilität as the likelihood of achieving a pregnancy per menstrual cycle, described and expressed in percent.
• Fecundity is the number of successful pregnancies per female individual.
• In a figurative sense is the fertility of a person or a people for their or his own creative power, creativity and strength.
• In the demographic a mathematical average size is used with the total fertility rate (TFR ), which determines the number of children that a (average) woman in their lives - usually between their 15th and 45th year of life - brings to the world.
• In geology, it is called a fertile mantle, if it is not already depleted in one of its chemical components by partial melting.

Disambiguation

The fertility of a plant species is a measure of the number of new plants that are produced at each reproductive cycle. It determines how strong this plant spreads in an area when the first plant of this type appear in this area new or how large the ability of this species is to preserve despite competition from other plant species in an area the stock of copies or strengthen.

Fertility in relation to human reproduction is a term that is deeply rooted in the history of mankind. He has two reasons to do with the continued existence:

• On the one hand by the farming and agriculture thus began more than 10,000 years ago, which has contributed significantly to the development of today's material culture. In this context, soil fertility, but also the fertility of cattle played an important role. There are numerous approaches to increase these forms of fertility and thus increase the yield. Fertilization of the soil or the breeding particularly easy to reproduce on -bringing livestock species are just two of the most commonly used methods.
• On the other hand by human fertility, so the fertility of men and the fecundity of women. In this context, we find consistently in all cultures fertility rites and symbols of fertility and in the religions and beliefs influence of deities.

External factors that alter the fertility

Temporal influences

The phase of human life, in which it is fertile and procreative, begins with puberty and ends for women with menopause ( menopause ). Men, however, may be able to have children well into old age. In general, the fertility increases but decreases with age.

The fertile period of the woman can be relatively accurately determined by means of Symptothermal method - this is often used for natural contraception.

Environmental factors

The fertility of people may be affected negatively with (environmental) toxins caused by conditions such as illness or stress. These include, for example, the consumption of alcohol or a chronic lead poisoning. Heavy smoking damages the uterus and reduces fertility, because the fertilized egg can implant itself in the endometrium difficult. In one study, half of the women who smoked, pregnant, in heavy smokers it was only a third of women.

Nutrition and health care, but also civilizing influences such as the presence of schools or the possibility of raising children and your own needs to coordinate with each other, also determine the fertility of any group of humanity, both in the States and in other groups (cities, regions, social groups ).

Fertility and mortality are the influence factors of natural increase. The most industrialized countries fall below around since the 1970s, the " magic threshold " of 2.1 children per woman, the so-called simple replacement level or even replacement level of fertility, below which decreases the population in the long term.