Editing Infertility (section)

=== Other causes ===
Factors that can cause male as well as female infertility are:
* DNA damage
** DNA damage reduces fertility in female ovocytes, as caused by smoking,<ref name=Zenzes>{{cite journal | vauthors = Zenzes MT | title = Smoking and reproduction: gene damage to human gametes and embryos | journal = Human Reproduction Update | volume = 6 | issue = 2 | pages = 122–131 | year = 2000 | pmid = 10782570 | doi = 10.1093/humupd/6.2.122 | doi-access = free }}</ref> other [[xenobiotic]] DNA damaging agents (such as radiation or chemotherapy)<ref>{{cite journal | vauthors = Mark-Kappeler CJ, Hoyer PB, Devine PJ | title = Xenobiotic effects on ovarian preantral follicles | journal = Biology of Reproduction | volume = 85 | issue = 5 | pages = 871–883 | date = November 2011 | pmid = 21697514 | pmc = 3197911 | doi = 10.1095/biolreprod.111.091173 }}</ref> or accumulation of the oxidative DNA damage 8-hydroxy-deoxyguanosine<ref>{{cite journal | vauthors = Seino T, Saito H, Kaneko T, Takahashi T, Kawachiya S, Kurachi H | title = Eight-hydroxy-2'-deoxyguanosine in granulosa cells is correlated with the quality of oocytes and embryos in an in vitro fertilization-embryo transfer program | journal = Fertility and Sterility | volume = 77 | issue = 6 | pages = 1184–1190 | date = June 2002 | pmid = 12057726 | doi = 10.1016/s0015-0282(02)03103-5 | doi-access = free }}</ref>
** DNA damage reduces fertility in male sperm, as caused by oxidative DNA damage,<ref>{{cite journal | vauthors = Gharagozloo P, Aitken RJ | title = The role of sperm oxidative stress in male infertility and the significance of oral antioxidant therapy | journal = Human Reproduction | volume = 26 | issue = 7 | pages = 1628–1640 | date = July 2011 | pmid = 21546386 | doi = 10.1093/humrep/der132 | doi-access = free }}</ref> smoking,<ref name=Zenzes /> other xenobiotic DNA damaging agents (such as drugs or chemotherapy)<ref>{{cite journal | vauthors = Nili HA, Mozdarani H, Pellestor F | title = Impact of DNA damage on the frequency of sperm chromosomal aneuploidy in normal and subfertile men | journal = Iranian Biomedical Journal | volume = 15 | issue = 4 | pages = 122–129 | year = 2011 | pmid = 22395136 | pmc = 3614247 | doi = 10.6091/ibj.990.2012 }}</ref> or other DNA-damaging agents, including reactive oxygen species, fever, or high testicular temperature.<ref>{{cite journal | vauthors = Shamsi MB, Imam SN, Dada R | title = Sperm DNA integrity assays: diagnostic and prognostic challenges and implications in management of infertility | journal = Journal of Assisted Reproduction and Genetics | volume = 28 | issue = 11 | pages = 1073–1085 | date = November 2011 | pmid = 21904910 | pmc = 3224170 | doi = 10.1007/s10815-011-9631-8 }}</ref> The damaged DNA related to infertility manifests itself by the increased susceptibility to denaturation inducible by heat or acid<ref>{{cite journal | vauthors = Evenson DP, Darzynkiewicz Z, Melamed MR | title = Relation of mammalian sperm chromatin heterogeneity to fertility | journal = Science | volume = 210 | issue = 4474 | pages = 1131–1133 | date = December 1980 | pmid = 7444440 | doi = 10.1126/science.7444440 | bibcode = 1980Sci...210.1131E }}</ref> or by the presence of double-strand breaks that can be detected by the [[TUNEL assay]].<ref>{{cite journal | vauthors = Gorczyca W, Traganos F, Jesionowska H, Darzynkiewicz Z | title = Presence of DNA strand breaks and increased sensitivity of DNA in situ to denaturation in abnormal human sperm cells: analogy to apoptosis of somatic cells | journal = Experimental Cell Research | volume = 207 | issue = 1 | pages = 202–205 | date = July 1993 | pmid = 8391465 | doi = 10.1006/excr.1993.1182 }}</ref> In this assay, the sperm's DNA will be denaturated and renatured. If DNA fragmentation occurs (double and single-strand breaks), a halo will not appear surrounding the spermatozoa, but if the spermatozoa do not have DNA damage, a halo surrounding the spermatozoa could be visualized under the microscope.
* General factors
** [[Diabetes mellitus]],<ref name= JangirJain>{{cite journal | vauthors = Jangir RN, Jain GC | title = Diabetes mellitus induced impairment of male reproductive functions: a review | journal = Current Diabetes Reviews | volume = 10 | issue = 3 | pages = 147–157 | date = May 2014 | pmid = 24919656 | doi = 10.2174/1573399810666140606111745 }}</ref><ref name= LivshitsSeidman>{{cite journal | vauthors = Livshits A, Seidman DS | title = Fertility issues in women with diabetes | journal = Women's Health | volume = 5 | issue = 6 | pages = 701–707 | date = November 2009 | pmid = 19863473 | doi = 10.2217/whe.09.47 | doi-access = free }}</ref> [[thyroid]] disorders,<ref name=Anreeva>{{cite journal | vauthors = Andreeva P | title = [Thyroid gland and fertility] | journal = Akusherstvo I Ginekologiia | volume = 53 | issue = 7 | pages = 18–23 | date = 2014 | pmid = 25675618 }}</ref> undiagnosed and untreated [[coeliac disease]],<ref name=TersigniCastellani>{{cite journal | vauthors = Tersigni C, Castellani R, de Waure C, Fattorossi A, De Spirito M, Gasbarrini A, Scambia G, Di Simone N | display-authors = 6 | title = Celiac disease and reproductive disorders: meta-analysis of epidemiologic associations and potential pathogenic mechanisms | journal = Human Reproduction Update | volume = 20 | issue = 4 | pages = 582–593 | date = 2014 | pmid = 24619876 | doi = 10.1093/humupd/dmu007 | quote = Physicians should investigate women with unexplained infertility, recurrent miscarriage or IUGR for undiagnosed CD. (...) CD can present with several non-gastrointestinal symptoms, and it may escape timely recognition. Thus, given the heterogeneity of clinical presentation, many atypical cases of CD go undiagnosed, leading to a risk of long-term complications. Among atypical symptoms of CD, disorders of fertility, such as delayed menarche, early menopause, amenorrhea or infertility, and pregnancy complications, such as recurrent abortions, intrauterine growth restriction (IUGR), small for gestational age (SGA) babies, low birthweight (LBW) babies or preterm deliveries, must be factored. (...) However, the risk is significantly reduced by a [[gluten]]-free diet. These patients should therefore be made aware of the potential negative effects of active CD also in terms of reproductive performance, and of the importance of a strict diet to ameliorate their health condition and reproductive health. | doi-access = free | hdl = 10807/56796 | hdl-access = free }}</ref><ref name=LasaZubiaurre>{{cite journal | vauthors = Lasa JS, Zubiaurre I, Soifer LO | title = Risk of infertility in patients with celiac disease: a meta-analysis of observational studies | journal = Arquivos de Gastroenterologia | volume = 51 | issue = 2 | pages = 144–150 | date = 2014 | pmid = 25003268 | doi = 10.1590/S0004-28032014000200014 | quote = Undiagnosed celiac disease is a risk factor for infertility. Women seeking medical advice for this particular condition should be screened for celiac disease. Adoption of a gluten-free diet could have a positive impact on fertility in this group of patients.(...)According to our results, non-diagnosed untreated CD constitutes a risk factor significantly associated with infertility in women. When comparing studies that enrolled patients previously diagnosed with CD, this association is not as evident as in the former context. This could be related to the effect that adoption of a gluten-free diet (GFD) may have on this particular health issue. | doi-access = free }}</ref><ref name=Hozyasz>{{cite journal | vauthors = Hozyasz K | title = [Coeliac disease and problems associated with reproduction] | journal = Ginekologia Polska | volume = 72 | issue = 3 | pages = 173–179 | date = March 2001 | pmid = 11398587 | quote = Coeliac men may have reversible infertility, and as in women, if gastrointestinal symptoms are mild or absent the diagnosis may be missed. It is important to make diagnosis because the giving of gluten free diet may result in conception and favourable outcome of pregnancy. }}</ref><ref name=SherJayanthi>{{cite journal | vauthors = Sher KS, Jayanthi V, Probert CS, Stewart CR, Mayberry JF | title = Infertility, obstetric and gynaecological problems in coeliac sprue | journal = Digestive Diseases | volume = 12 | issue = 3 | pages = 186–190 | date = 1994 | pmid = 7988065 | doi = 10.1159/000171452 | quote = There is now substantial evidence that coeliac sprue is associated with infertility both in men and women. (...) In men it can cause hypogonadism, immature secondary sex characteristics and reduce semen quality. (...) Hyperprolactinaemia is seen in 25% of coeliac patients, which causes impotence and loss of libido. Gluten withdrawal and correction of deficient dietary elements can lead to a return of fertility both in men and women. }}</ref> [[adrenal]] disease<ref name=ReichmanWhite>{{cite journal | vauthors = Reichman DE, White PC, New MI, Rosenwaks Z | title = Fertility in patients with congenital adrenal hyperplasia | journal = Fertility and Sterility | volume = 101 | issue = 2 | pages = 301–309 | date = February 2014 | pmid = 24355046 | doi = 10.1016/j.fertnstert.2013.11.002 | doi-access = free }}</ref>
* Hypothalamic-pituitary factors
** [[Hyperprolactinemia]]
** [[Hypopituitarism]]
** The presence of [[anti-thyroid antibodies]] is associated with an increased risk of unexplained subfertility with an [[odds ratio]] of 1.5 and 95% [[confidence interval]] of 1.1–2.0.<ref>{{cite journal | vauthors = van den Boogaard E, Vissenberg R, Land JA, van Wely M, van der Post JA, Goddijn M, Bisschop PH | title = Significance of (sub)clinical thyroid dysfunction and thyroid autoimmunity before conception and in early pregnancy: a systematic review | journal = Human Reproduction Update | volume = 17 | issue = 5 | pages = 605–619 | year = 2011 | pmid = 21622978 | doi = 10.1093/humupd/dmr024 | url = https://pure.rug.nl/ws/files/39886084/Corrigendum_Significance_of_sub_clinical_thyroid_dysfunction_and_thyroid_autoimmunity_before_conception_and_in_early_pregnancy.pdf | access-date = 19 September 2019 | url-status = live | doi-access = free | archive-url = https://web.archive.org/web/20190218060751/https://pure.rug.nl/ws/files/39886084/Corrigendum_Significance_of_sub_clinical_thyroid_dysfunction_and_thyroid_autoimmunity_before_conception_and_in_early_pregnancy.pdf | archive-date = 18 February 2019 }}</ref>
* Environmental factors
** [[Toxin]]s such as glues, volatile organic [[solvents]] or [[silicone]]s, physical agents, flame retardants, chemical dusts, [[Polychlorinated biphenyl|polychlorinated biphenyls]], and [[pesticides]].<ref>{{cite journal | vauthors = Mendiola J, Torres-Cantero AM, Moreno-Grau JM, Ten J, Roca M, Moreno-Grau S, Bernabeu R | title = Exposure to environmental toxins in males seeking infertility treatment: a case-controlled study | journal = Reproductive Biomedicine Online | volume = 16 | issue = 6 | pages = 842–850 | date = June 2008 | pmid = 18549695 | doi = 10.1016/S1472-6483(10)60151-4 | doi-access = free }}</ref><ref>{{cite journal | vauthors = Smith EM, Hammonds-Ehlers M, Clark MK, Kirchner HL, Fuortes L | title = Occupational exposures and risk of female infertility | journal = Journal of Occupational and Environmental Medicine | volume = 39 | issue = 2 | pages = 138–147 | date = February 1997 | pmid = 9048320 | doi = 10.1097/00043764-199702000-00011 }}</ref><ref>{{Cite journal |last1=Björvang |first1=Richelle D. |last2=Damdimopoulou |first2=Pauliina |date=2020-04-02 |title=Persistent environmental endocrine-disrupting chemicals in ovarian follicular fluid and in vitro fertilization treatment outcome in women |url=https://ujms.net/index.php/ujms/article/view/5630 |journal=Upsala Journal of Medical Sciences |language=en |volume=125 |issue=2 |pages=85–94 |doi=10.1080/03009734.2020.1727073 |issn=0300-9734 |pmc=7721012 |pmid=32093529}}</ref><ref>{{Cite journal |last1=Björvang |first1=Richelle D. |last2=Hallberg |first2=Ida |last3=Pikki |first3=Anne |last4=Berglund |first4=Lars |last5=Pedrelli |first5=Matteo |last6=Kiviranta |first6=Hannu |last7=Rantakokko |first7=Panu |last8=Ruokojärvi |first8=Päivi |last9=Lindh |first9=Christian H. |last10=Olovsson |first10=Matts |last11=Persson |first11=Sara |last12=Holte |first12=Jan |last13=Sjunnesson |first13=Ylva |last14=Damdimopoulou |first14=Pauliina |date=May 2022 |title=Follicular fluid and blood levels of persistent organic pollutants and reproductive outcomes among women undergoing assisted reproductive technologies |journal=Environmental Research |language=en |volume=208 |pages=112626 |doi=10.1016/j.envres.2021.112626|pmid=34973191 |s2cid=245581454 |doi-access=free |bibcode=2022ER....20812626B }}</ref> [[Tobacco smoker]]s are 60% more likely to be infertile than non-smokers.<ref name=dh2009>{{cite web | url = http://www.dh.gov.uk/en/Publicationsandstatistics/Publications/PublicationsPolicyAndGuidance/DH_101070 | title = Regulated fertility services: a commissioning aid | date = June 2009 | archive-url = https://web.archive.org/web/20110103051232/http://www.dh.gov.uk/en/Publicationsandstatistics/Publications/PublicationsPolicyAndGuidance/DH_101070 | archive-date=3 January 2011 | work = Department of Health UK }}</ref>

Other diseases such as [[chlamydia infection|chlamydia]], and [[gonorrhea]] can also cause infertility, due to internal scarring ([[fallopian tube obstruction]]).<ref>{{cite web|url=https://www.cdc.gov/std/infertility/|title=Infertility & STDs - STD Information from CDC|website=cdc.gov|date=2019-01-11|access-date=9 September 2017|archive-date=17 August 2017|archive-url=https://web.archive.org/web/20170817195816/https://www.cdc.gov/std/infertility/|url-status=live}}</ref><ref>{{cite web|url=http://www.livestrong.com/article/1007744-stds-can-cause-infertility/|title=STDs That Can Cause Infertility| vauthors = Wittenberg ME |website=LIVESTRONG.COM|access-date=3 December 2014|archive-date=24 November 2014|archive-url=https://web.archive.org/web/20141124161610/http://www.livestrong.com/article/1007744-stds-can-cause-infertility/|url-status=live}}</ref><ref>{{cite web|url=http://health.howstuffworks.com/pregnancy-and-parenting/pregnancy/fertility/5-most-common-causes-of-infertility.htm#page=5|title=5 Most Common Causes of Infertility|website=HowStuffWorks|date=2011-02-17|access-date=3 December 2014|archive-date=14 December 2014|archive-url=https://web.archive.org/web/20141214051205/http://health.howstuffworks.com/pregnancy-and-parenting/pregnancy/fertility/5-most-common-causes-of-infertility.htm#page=5|url-status=live}}</ref>

*Body mass, the [[Body Mass Index|BMI]] (body mass index) (either being too high or too low) may be a contributor to infertility.
** [[Obesity]]: Obesity can have a significant impact on male and female fertility. In females, a BMI above 27 increases the risk of infertility 3-fold.<ref name="Carson 2021" /> Obese women have a higher rate of recurrent, early miscarriage compared to non-obese women.{{Citation needed|date=October 2024}} In males, an increase in BMI above 30 may be associated with reduced sperm quality and impaired [[spermatogenesis]] leading to infertility.<ref name="Ameratunga 2023">{{cite journal |last1=Ameratunga |first1=Devini |last2=Gebeh |first2=Alpha |last3=Amoako |first3=Akwasi |title=Obesity and male infertility |journal=Best Practice & Research Clinical Obstetrics & Gynaecology |date=August 2023 |volume=90 |pages=102393 |doi=10.1016/j.bpobgyn.2023.102393}}</ref> In males, a high BMI is also associated with low testosterone levels (secondary hypogonadism) and [[erectile dysfunction]], which contributes to infertility.<ref name="Ameratunga 2023" />
** Low weight: females with a very low BMI may have infertility. Common causes of low BMI leading to infertility include [[anorexia nervosa]] and other eating disorders, excessive exercise or [[relative energy deficiency in sport]].<ref name="Carson 2021" /> Infertility in females with a low BMI is usually due to [[functional hypothalamic amenorrhea]] due to stress-induced inhibition of the [[hypothalamic-pituitary-gonadal axis|hypothalamic pituitary ovarian axis]].<ref name="Carson 2021" />