Editing Infertility (section)

==Definition==
"Demographers tend to define infertility as childlessness in a population of women of reproductive age," whereas the epidemiological definition refers to "trying for" or "time to" a pregnancy, generally in a population of women exposed to a probability of conception.<ref name="Doihumupddmr">{{cite journal | vauthors = Gurunath S, Pandian Z, Anderson RA, Bhattacharya S | title = Defining infertility--a systematic review of prevalence studies | journal = Human Reproduction Update | volume = 17 | issue = 5 | pages = 575–588 | year = 2011 | pmid = 21493634 | doi = 10.1093/humupd/dmr015 | doi-access = free }}</ref> Currently, female fertility normally peaks in young adulthood and diminishes after 35 with pregnancy occurring rarely after age 50. A female is most fertile within 24 hours of ovulation. Male fertility peaks usually in young adulthood and declines after age 40.<ref name=":0">{{Cite book|title=Diseases of the Human Body |url= https://archive.org/details/diseaseshumanbod00tamp_971|url-access=limited| vauthors = Tamparo C, Lewis M |publisher=F.A. Davis Company|year=2011|isbn=9780803625051|location=Philadelphia, PA|pages=[https://archive.org/details/diseaseshumanbod00tamp_971/page/n486 459]}}</ref>

The time needed to pass (during which the couple tries to conceive) for that couple to be diagnosed with infertility differs between different organizations. Existing definitions of infertility lack uniformity, rendering comparisons in prevalence between countries or over time problematic. Therefore, data estimating the prevalence of infertility cited by various sources differ significantly.<ref name="Doihumupddmr" /> A couple that tries unsuccessfully to have a child after a certain period (often a short period, but definitions vary) is sometimes said to be '''subfertile''', meaning less fertile than a typical couple. Both infertility and subfertility are defined similarly and often used interchangeably, but subfertility is the delay in conceiving within six to twelve months, whereas infertility is the inability to conceive naturally within a full year.<ref>{{Cite web |last=RMIA |date=2021-10-20 |title=Subfertility Or Infertility: Is It Time To Consider IVF? |url=https://www.rmia.com/fertility-treatments/subfertility-or-infertility-is-it-time-to-consider-ivf/ |access-date=2023-08-03 |website=Reproductive Medicine & Infertility Associates |language=en-US}}</ref>

===World Health Organization===
The [[World Health Organization]] defines infertility as follows:<ref>{{cite web|url=https://www.who.int/reproductivehealth/topics/infertility/definitions/en/ |archive-url=https://web.archive.org/web/20131023231051/http://www.who.int/reproductivehealth/topics/infertility/definitions/en/ |url-status=dead |archive-date=23 October 2013 |title=WHO &#124; Infertility |publisher=Who.int |date=2013-03-19 |access-date=2013-06-17}}</ref>

{{Blockquote|Infertility is "a disease of the reproductive system defined by the failure to achieve a clinical pregnancy after 12 months or more of regular unprotected [[Human reproduction#Copulation|sexual intercourse]] (and there is no other reason, such as breastfeeding or postpartum [[amenorrhoea]]). Primary infertility is infertility in a couple who have never had a child. Secondary infertility is the failure to conceive following a previous pregnancy. Infertility may be caused by infection in the man or woman, but often there is no obvious underlying cause."}}

===United States===
One definition of infertility that is frequently used in the United States by [[reproductive endocrinologist]]s, doctors who specialize in infertility, to consider a couple eligible for treatment is:
* a woman under 35 has not conceived after 12 months of contraceptive-free intercourse.
* a woman over 35 has not conceived after six months of contraceptive-free [[sexual intercourse]].

===United Kingdom===
In the UK, previous [[NICE guideline]]s defined infertility as failure to conceive after regular unprotected sexual intercourse for two years in the absence of known reproductive pathology.<ref name=nice>{{cite book |title=Fertility: Assessment and Treatment for People with Fertility Problems |publisher=RCOG Press |location=London |year=2004 |isbn=978-1-900364-97-3 |url=http://www.nice.org.uk/nicemedia/pdf/CG011publicinfoenglish.pdf |url-status=dead |archive-url=https://web.archive.org/web/20101115121046/http://www.nice.org.uk/nicemedia/pdf/CG011publicinfoenglish.pdf |archive-date=15 November 2010}}</ref> Updated NICE guidelines do not include a specific definition, but recommend that "A woman of reproductive age who has not conceived after 1 year of unprotected vaginal sexual intercourse, in the absence of any known cause of infertility, should be offered further clinical assessment and investigation along with her partner, with earlier referral to a specialist if the woman is over 36 years of age."<ref>{{cite web|url=http://guidance.nice.org.uk/CG156|title=Fertility: assessment and treatment for people with fertility problems, section: Defining infertility|website=[[NICE Clinical guidelines]], CG156|date=February 2013|access-date=14 February 2014|archive-date=23 February 2013|archive-url=https://web.archive.org/web/20130223023043/http://guidance.nice.org.uk/CG156|url-status=live}}</ref>

===Other definitions===
Researchers commonly base demographic studies on infertility prevalence over five years.<ref>{{cite web |url=https://www.who.int/reproductivehealth/topics/infertility/DHS-CR9.pdf | title = Infecundity, Infertility, and Childlessness in Developing Countries | publisher = World Health Organization |archive-url=https://web.archive.org/web/20201116015959/https://www.who.int/reproductivehealth/topics/infertility/DHS-CR9.pdf |archive-date=16 November 2020  |url-status=}}</ref>

===Primary vs. secondary infertility===
Primary infertility is defined as the absence of a live birth for women who desire a child and have been in a union for at least 12 months, during which they have not used any contraceptives.<ref name="who.int"/> The World Health Organisation also adds that 'women whose pregnancy spontaneously miscarries, or whose pregnancy results in a stillborn child, without ever having had a live birth, would present with primarily infertility'.<ref name="who.int">{{Cite web | url=https://www.who.int/reproductivehealth/topics/infertility/definitions/en/ | archive-url=https://web.archive.org/web/20131023231051/http://www.who.int/reproductivehealth/topics/infertility/definitions/en/ | url-status=dead | archive-date=23 October 2013 | title=WHO &#124; Infertility definitions and terminology}}</ref>

Secondary infertility is defined as the difficulty in conceiving a live birth in couples who previously had a child.<ref name="who.int"/>