Editing Intracytoplasmic sperm injection (section)

== Success or failure factors ==
One of the areas in which sperm injection can be useful is vasectomy reversal. However, potential factors that may influence [[pregnancy rates]] (and live birth rates) in ICSI include level of [[DNA fragmentation]]<ref name="speyer">{{cite journal | vauthors = Speyer BE, Pizzey AR, Ranieri M, Joshi R, Delhanty JD, Serhal P | title = Fall in implantation rates following ICSI with sperm with high DNA fragmentation | journal = Human Reproduction | volume = 25 | issue = 7 | pages = 1609–1618 | date = July 2010 | pmid = 20495207 | doi = 10.1093/humrep/deq116 | doi-access =  }}</ref> as measured e.g. by [[comet assay]], [[advanced maternal age]] and [[semen quality]]. It is uncertain whether ICSI improves live birth rates or reduces the risk of miscarriage compared with [[Intracytoplasmic morphologically selected sperm injection|ultra‐high magnification (IMSI)]] sperm selection.<ref>{{cite journal | vauthors = Teixeira DM, Hadyme Miyague A, Barbosa MA, Navarro PA, Raine-Fenning N, Nastri CO, Martins WP | title = Regular (ICSI) versus ultra-high magnification (IMSI) sperm selection for assisted reproduction | journal = The Cochrane Database of Systematic Reviews | volume = 2020 | issue = 2 | pages = CD010167 | date = February 2020 | pmid = 32083321 | pmc = 7033651 | doi = 10.1002/14651858.CD010167.pub3 }}</ref>

A systematic meta-analysis of 24 estimates of [[DNA damage (naturally occurring)|DNA damage]] based on a variety of techniques concluded that [[sperm]] DNA damage negatively affects clinical pregnancy following ICSI.<ref name="pmid27345006">{{cite journal | vauthors = Simon L, Zini A, Dyachenko A, Ciampi A, Carrell DT | title = A systematic review and meta-analysis to determine the effect of sperm DNA damage on ''in vitro'' fertilization and intracytoplasmic sperm injection outcome | journal = Asian Journal of Andrology | volume = 19 | issue = 1 | pages = 80–90 | year = 2017 | pmid = 27345006 | pmc = 5227680 | doi = 10.4103/1008-682X.182822 | doi-access = free }}</ref>

Numerous biochemical markers were shown to be associated with oocyte quality for ICSI.<ref name="pmid19413899">{{cite journal | vauthors = Revelli A, Delle Piane L, Casano S, Molinari E, Massobrio M, Rinaudo P | title = Follicular fluid content and oocyte quality: from single biochemical markers to metabolomics | journal = Reproductive Biology and Endocrinology | volume = 7 | issue = | pages = 40 | date = May 2009 | pmid = 19413899 | pmc = 2685803 | doi = 10.1186/1477-7827-7-40 | doi-access = free }}</ref> For example, it was shown that after ICSI the follicular fluid of unfertilized oocytes contains high levels of cytotoxicity and oxidative stress markers, as Cu,Zn-superoxide dismutase, catalase, and lipoperoxidation product [[4-hydroxynonenal]] ([[4-HNE]]) -protein conjugates.<ref name="pmid28645283">{{cite journal | vauthors = Revelli A, Canosa S, Bergandi L, Skorokhod OA, Biasoni V, Carosso A, Bertagna A, Maule M, Aldieri E, D'Eufemia MD, Evangelista F, Colacurci N, Benedetto C | display-authors = 6 | title = Oocyte polarized light microscopy, assay of specific follicular fluid metabolites, and gene expression in cumulus cells as different approaches to predict fertilization efficiency after ICSI | journal = Reproductive Biology and Endocrinology | volume = 15 | issue = 1 | pages = 47 | date = June 2017 | pmid = 28645283 | pmc = 5481970 | doi = 10.1186/s12958-017-0265-2 | doi-access = free }}</ref>