Fertility

From Free net encyclopedia

Fertility is the ability of people or animals to produce healthy offspring in abundance. In the English language, the term was originally applied only to females, but increasingly is applied to males as well, as common understanding of reproductive mechanisms increases and the importance of the male role is better known.

Human fertility depends on factors of nutrition, sexual behavior, culture, instinct, endocrinology, timing, economics, way of life, and emotions. Animal fertility is no less complex, and may display astounding mechanisms.

The opposite is infertility. Some fertility issues here.

By extension, fertility is also applied to farmlands and plants, and a large crop of sound fruits, seeds or vegetables is the expectation.

The fertility rate is a demographic measure of the number of children per woman. Although it has been until recently considered to be a fairly reliable indicator of population growth, it is no longer so in much of Asia. Due to selective abortion and other factors, the number of women themselves is declining. Therefore, the fertility rate as it has traditionally been defined is no longer an authoritative measure of population growth in China, India, and Myanmar.

Both women and men have hormonal cycles which determine both when a woman can achieve pregnancy and when a man is most fertile. The female cycle is approximately twenty-eight days long, but the male cycle is variable. Women ovulate at about the fourteenth day of their cycle, this obviously being the most fertile time for females. Men can ejaculate and produce sperm at any time of the month, but their libido dips occasionally, which scientists guess is in relation to their internal cycle. During the fourteenth week of fetal growth, a women’s eggs (or ova) form in her ovaries, where they will remain until puberty. At puberty, the eggs will eventually start to mature one-by-one. At ovulation, the egg bursts from the ovary sometimes causing a small, sharp pain called mittelschmerz. If the egg is not fertilized by the male’s sperm, the egg will break down within twenty-four hours into its components (mostly protein) and be reabsorbed by the body.

cs:Plodnost (rozcestník) da:Frugtbarhed de:Fruchtbarkeit es:Fertilidad fr:Fertilité lt:Vaisingumas nl:Vruchtbaarheid sv:Fertilitet