Editing In vitro fertilisation (section)

===Natural IVF===
{{Main|Natural cycle in vitro fertilisation}}
There are several methods termed natural cycle IVF:<ref name="Allersma2013">{{cite journal | vauthors = Allersma T, Farquhar C, Cantineau AE | title = Natural cycle in vitro fertilisation (IVF) for subfertile couples | journal = The Cochrane Database of Systematic Reviews | volume = 2013 | issue = 8 | pages = CD010550 | date = August 2013 | pmid = 23990351 | pmc = 7390465 | doi = 10.1002/14651858.CD010550.pub2 }}</ref>
* IVF using no drugs for [[Controlled ovarian hyperstimulation|ovarian hyperstimulation]], while drugs for [[ovulation suppression]] may still be used.
* IVF using ovarian hyperstimulation, including gonadotropins, but with a [[GnRH antagonist]] protocol so that the cycle initiates from natural mechanisms.
* [[Frozen embryo transfer]]; IVF using [[Controlled ovarian hyperstimulation|ovarian hyperstimulation]], followed by [[embryo cryopreservation]], followed by [[embryo transfer]] in a later, natural, cycle.<ref name="EvansHannan2014">{{cite journal | vauthors = Evans J, Hannan NJ, Edgell TA, Vollenhoven BJ, Lutjen PJ, Osianlis T, Salamonsen LA, Rombauts LJ | display-authors = 6 | title = Fresh versus frozen embryo transfer: backing clinical decisions with scientific and clinical evidence | journal = Human Reproduction Update | volume = 20 | issue = 6 | pages = 808–821 | year = 2014 | pmid = 24916455 | doi = 10.1093/humupd/dmu027 | doi-access = free }}</ref>

IVF using no drugs for ovarian hyperstimulation was the method for the conception of [[Louise Brown]]. This method can be successfully used when people want to avoid taking ovarian stimulating drugs with its associated side-effects. [[Human Fertilisation and Embryology Authority|HFEA]] has estimated the [[live birth rate]] to be approximately 1.3% per IVF cycle using no hyperstimulation drugs for women  aged between 40 and 42.<ref>{{cite web | url = http://www.hfea.gov.uk/natural-cycle-ivf.html | title = Natural cycle IVF | archive-url = https://web.archive.org/web/20120512083412/http://www.hfea.gov.uk/natural-cycle-ivf.html | archive-date=12 May 2012 | work = [[Human Fertilisation and Embryology Authority]] }}</ref>

Mild IVF<ref>{{cite journal | vauthors = Nargund G | title = Natural/mild assisted reproductive technologies: reducing cost and increasing safety | journal = Women's Health | volume = 5 | issue = 4 | pages = 359–360 | date = July 2009 | pmid = 19586428 | doi = 10.2217/whe.09.32 | doi-access = free }}</ref> is a method where a small dose of ovarian stimulating drugs are used for a short duration during a natural menstrual cycle aimed at producing 2–7 eggs and creating healthy embryos. This method appears to be an advance in the field to reduce complications and side-effects for women, and it is aimed at quality, and not quantity of eggs and embryos. One study comparing a mild treatment (mild ovarian stimulation with GnRH antagonist co-treatment combined with [[single embryo transfer]]) to a standard treatment (stimulation with a [[GnRH agonist]] long-protocol and transfer of two embryos) came to the result that the proportions of cumulative pregnancies that resulted in term [[Live birth (human)|live birth]] after 1 year were 43.4% with mild treatment and 44.7% with standard treatment.<ref name="pmid17336650">{{cite journal | vauthors = Heijnen EM, Eijkemans MJ, De Klerk C, Polinder S, Beckers NG, Klinkert ER, Broekmans FJ, Passchier J, Te Velde ER, Macklon NS, Fauser BC | display-authors = 6 | title = A mild treatment strategy for in-vitro fertilisation: a randomised non-inferiority trial | journal = Lancet | volume = 369 | issue = 9563 | pages = 743–749 | date = March 2007 | pmid = 17336650 | doi = 10.1016/S0140-6736(07)60360-2 | s2cid = 25591825 }}</ref> Mild IVF can be cheaper than conventional IVF and with a significantly reduced risk of [[multiple birth|multiple gestation]] and [[ovarian hyperstimulation syndrome|OHSS]].<ref>{{cite journal | vauthors = Fauser BC, Nargund G, Andersen AN, Norman R, Tarlatzis B, Boivin J, Ledger W | title = Mild ovarian stimulation for IVF: 10 years later | journal = Human Reproduction | volume = 25 | issue = 11 | pages = 2678–2684 | date = November 2010 | pmid = 20858698 | doi = 10.1093/humrep/deq247 | doi-access = free }}</ref>