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A 2023 map of countries by fertility rate. Blue indicates negative fertility rates. Red indicates positive rates. The total fertility rate (TFR) of a population is the average number of children that are born to a woman over her lifetime, if they were to experience the exact current age-specific fertility rates (ASFRs) through their lifetime, and they were to live from birth until the end of ...
Birth rate, also known as natality, is the total number of live human births per 1,000 population for a given period divided by the length of the period in years. [1] The number of live births is normally taken from a universal registration system for births; population counts from a census, and estimation through specialized demographic ...
A sex ratio is the ratio of males to females in a population. As explained by Fisher's principle, for evolutionary reasons this is typically about 1:1 in species which reproduce sexually. [2][3] However, many species deviate from an even sex ratio, either periodically or permanently. Examples include parthenogenic species, periodically mating ...
The human sex ratio is the ratio of males to females in a population in the context of anthropology and demography. In humans, the natural sex ratio at birth is slightly biased towards the male sex. It is estimated to be about 1.05 [1] or 1.06 [2] or within a narrow range from 1.03 to 1.06 [3] males per female.
A semen analysis (plural: semen analyses), also called seminogram or spermiogram, evaluates certain characteristics of a male's semen and the sperm contained therein. [1][2][3] It is done to help evaluate male fertility, whether for those seeking pregnancy or verifying the success of vasectomy. Depending on the measurement method, just a few ...
The specific problem is: due to unclear definitions for fertility, fecundity and derivative terms depending on whether the term is being used in demography, epidemiology or clinical medicine. For example fecundity is the potential to for a female to become pregnant and carry that pregnancy to a live birth in demography, while in clinical ...
Male infertility refers to a sexually mature male's inability to impregnate a fertile female. [1] In humans, it accounts for 40–50% of infertility. [2][3][4][5] It affects approximately 7% of all men. [6] Male infertility is commonly due to deficiencies in the semen, and semen quality is used as a surrogate measure of male fecundity. [7]
Fertility. Fertility in colloquial terms refers the ability to have offspring. In demographic contexts, fertility refers to the actual production of offspring, rather than the physical capability to reproduce, which is termed fecundity. [1][2] The fertility rate is the average number of children born during an individual's lifetime. In medicine ...