Fertility

Fertility is the ability to conceive a child. The fertility rate is the average number of children born during an individual's lifetime and is quantified demographically. Conversely, infertility is the difficulty or inability to reproduce naturally. In general, infertility is defined as not being able to conceive a child after one year (or longer) of unprotected sex.^[1] Because infertility is widespread, fertility specialists all over the world assist persons and couples who experience difficulties conceiving a baby.

This article is about fertility in humans. For fertility of other organisms, see fecundity. For fertility of plants and soil, see Soil fertility.

Fertility is an issue for people of both sexes. According to the Centers for Disease Control and Prevention, in 35% of couples who cannot conceive, the cause can be attributed to factors on both the female and male side.^[1] Human fertility depends on various factors including nutrition, sexual behaviour, consanguinity, culture, instinct, endocrinology, timing of conception, economics, personality,^[2] lifestyle, and emotions.

Fertility differs from fecundity, which is defined as the biological capacity to reproduce irrespective of intention for conception.^[3] Fecundity can be explained by gamete production, fertilization, and carrying a pregnancy to term.^[4] The antithesis of fertility is infertility, while the antithesis of fecundity is sterility.

(CBR) - the number of live births in a given year per 1,000 people alive at the middle of that year. One disadvantage of this indicator is that it is influenced by the age structure of the population.

Crude birth rate

General fertility rate (GFR) - the number of births in a year divided by the number of women aged 15–44, times 1000. It focuses on the potential mothers only, and takes the age distribution into account.

Child-Woman Ratio (CWR) - the ratio of the number of children under 5 to the number of women 15–49, times 1000. It is especially useful in historical data as it does not require counting births. This measure is actually a hybrid, because it involves deaths as well as births. (That is, because of some of the births are not included; and because of adult mortality, some of the women who gave birth are not counted either.)

infant mortality

- a special device used in historical research

Coale's Index of Fertility

Impact of external factors on fertility[edit]

Studies have been conducted to identify external factors that impact fertility rates and embryo development. Two main factors were determined to have the greatest impact, eating habits and lifestyle choices.^[64] Eating choices include quality, types and frequency of food intake. Grains, fruits and vegetables have a positive influence on embryo quality. Alcohol intake, cigarette and marijuana use all have a detrimental impact on female reproductive function.^[65] During embryogenesis, the DNA structure and expression can be heavily influenced by lifestyle, nutrition and environmental toxins.^[66]

Bloom, David E.; Kuhn, Michael; Prettner, Klaus (2024). "". Annual Review of Economics.

Fertility in High-Income Countries: Trends, Patterns, Determinants, and Consequences

. Human Fertilisation and Embryology Authority (HFEA). Archived from the original on 2009-08-31.

"Fertility treatment and clinics in the UK"

. United States. Commission on Population Growth and the American Future. (Report). Washington: The Superintendent of Documents, U.S. Government Printing Office. 1972. hdl:2027/mdp.39015007261855.

Population and the American future: the report

. Archived from the original on 2010-07-09.

"United Nations World Population Prospects, the 2008 Revision"

Calder, Vanessa Brown, and Chelsea Follett (August 10, 2023). , Policy Analysis no. 955, Cato Institute, Washington, DC.