View source for Chemistry:Estradiol-containing birth control pill

{{Infobox Birth control
|name = Estradiol-containing oral contraceptive
|bc_type = Hormonal
|date_first_use = 1993 ({{wipe|Finland}})
|reversibility = Yes
|STD_protection_YesNo = No
}}

Combined birth control pills that contain natural [[Chemistry:Estradiol (medication)|estradiol]] or an estradiol ester (e.g., [[Chemistry:Estradiol valerate|estradiol valerate]]) include:<ref name="pmid27307386">{{cite journal | vauthors = De Leo V, Musacchio MC, Cappelli V, Piomboni P, Morgante G | title = Hormonal contraceptives: pharmacology tailored to women's health | journal = Human Reproduction Update | volume = 22 | issue = 5 | pages = 634–46 | year = 2016 | pmid = 27307386 | doi = 10.1093/humupd/dmw016 | doi-access = free }}</ref><ref name="pmid23375353">{{cite journal | vauthors = Stanczyk FZ, Archer DF, Bhavnani BR | title = Ethinyl estradiol and 17β-estradiol in combined oral contraceptives: pharmacokinetics, pharmacodynamics and risk assessment | journal = Contraception | volume = 87 | issue = 6 | pages = 706–27 | year = 2013 | pmid = 23375353 | doi = 10.1016/j.contraception.2012.12.011 }}</ref><ref name="pmid20004267">{{cite journal | vauthors = Fruzzetti F, Bitzer J | title = Review of clinical experience with estradiol in combined oral contraceptives | journal = Contraception | volume = 81 | issue = 1 | pages = 8–15 | year = 2010 | pmid = 20004267 | doi = 10.1016/j.contraception.2009.08.010 }}</ref>

* [[Chemistry:Estradiol valerate|Estradiol valerate]] and [[Chemistry:Cyproterone acetate|cyproterone acetate]] (brand name Femilar) – introduced in {{wipe|Finland}} (only) in 1993<ref name="pmid20004267" />
* Estradiol valerate and [[Chemistry:Dienogest|dienogest]] (brand names Qlaira, Natazia) – introduced in [[Earth:Europe|Europe]] in 2009 and the {{abbrlink|U.S.|United States}} in 2010<ref name="pmid21151673">{{cite journal | vauthors = Guida M, Bifulco G, Di Spiezio Sardo A, Scala M, Fernandez LM, Nappi C | title = Review of the safety, efficacy and patient acceptability of the combined dienogest/estradiol valerate contraceptive pill | journal = International Journal of Women's Health | volume = 2 | pages = 279–90 | year = 2010 | pmid = 21151673 | pmc = 2990895 | doi = 10.2147/IJWH.S6954 | doi-access = free }}</ref>
* [[Chemistry:Estradiol (medication)|Estradiol]] and [[Chemistry:Nomegestrol acetate|nomegestrol acetate]] (brand name Zoely) – introduced in Europe in 2011<ref name="pmid23836965">{{cite journal | vauthors = Burke A | title = Nomegestrol acetate-17b-estradiol for oral contraception | journal = Patient Preference and Adherence | volume = 7 | pages = 607–19 | year = 2013 | pmid = 23836965 | pmc = 3702550 | doi = 10.2147/PPA.S39371 | doi-access = free }}</ref>

Estradiol, mainly as esters including estradiol valerate, [[Chemistry:Estradiol cypionate|estradiol cypionate]], and estradiol enanthate, is also the exclusive estrogen used in combined injectable contraceptives.<ref>{{Cite journal|url=http://www.wjpps.com/download/article/1412071798.pdf|title = WJPPS &#124; ABSTRACT|journal = World Journal of Pharmacy and Pharmaceutical Sciences}}</ref>

As of 2021, more than 95% of prescriptions are for combined hormonal birth control forms containing the synthetic estrogen [[Chemistry:Ethinylestradiol|ethinylestradiol]] (EE).<ref name="MawetGaspard2021">{{cite journal | last1 = Mawet | first1 = M | last2 = Gaspard | first2 = Ulysse | last3 = Foidart | first3 = JM | title = Estetrol as estrogen in a combined oral contraceptive, from the first in-human study to the contraceptive efficacy | journal = European Gynecology and Obstetrics | volume = 3 | issue = 1 | pages = 13–21 | year = 2021 | url = https://www.egojournal.eu/wp-content/uploads/journal/2021/3.1/13/13-21.pdf | quote = On the other side, only three different estrogens have been used in COC since 1961: the first one was the pro-drug mestranol rapidly replaced by its potent active form, ethinylestradiol (EE). Ethinylestradiol has remained the only estrogen used in COC during more than four decades. After initial unsuccessful attempts, estradiol (E2) was finally introduced into two COCs in the early 2010’: in the form of the pro-drug E2 valerate in combination with dienogest (E2V/DNG) and in the form of E2 in combination with nomegestrol acetate [4, 5]. However, these E2-containing COCs are less prescribed as over 95% of combined hormonal contraceptive users still utilize an EE-containing product.}}</ref> Hence, estradiol-based birth control pills are still not widely used.<ref name="MawetGaspard2021" />

==Side effects==
Birth control pills containing estradiol have less impact on liver protein synthesis than [[Chemistry:Ethinylestradiol|ethinylestradiol]]-containing birth control pills, and it is thought that for this reason, they may pose less of a risk of venous thromboembolism (VTE).<ref name="pmid26512437">{{cite journal | vauthors = Nelson AL | title = An update on new orally administered contraceptives for women | journal = Expert Opinion on Pharmacotherapy | volume = 16 | issue = 18 | pages = 2759–72 | year = 2015 | pmid = 26512437 | doi = 10.1517/14656566.2015.1100173 | s2cid = 207481206 }}</ref><ref name="JensenBitzer2013" /> In accordance, although birth control pills containing estradiol valerate/dienogest are associated with a significantly increased risk of VTE, they are associated with a significantly lower risk of venous thromboembolism than birth control pills containing ethinylestradiol and a progestin.<ref name="pmid30519125">{{cite journal | vauthors = Fruzzetti F, Cagnacci A | title = Venous thrombosis and hormonal contraception: what's new with estradiol-based hormonal contraceptives? | journal = Open Access J Contracept | volume = 9 | pages = 75–79 | date = 2018 | pmid = 30519125 | pmc = 6239102 | doi = 10.2147/OAJC.S179673 | doi-access = free }}</ref> The risk of VTE with estradiol/nomegestrol acetate birth control pills is under study.<ref name="pmid33080636">{{cite journal | vauthors = Douxfils J, Morimont L, Bouvy C | title = Oral Contraceptives and Venous Thromboembolism: Focus on Testing that May Enable Prediction and Assessment of the Risk | journal = Semin Thromb Hemost | date = October 2020 | volume = 46 | issue = 8 | pages = 872–886 | pmid = 33080636 | doi = 10.1055/s-0040-1714140 | s2cid = 224821517 }}</ref>

Incidence of irregular vaginal bleeding may be higher with estradiol-containing birth control pills in relation to the fact that estradiol is a weaker estrogen than ethinylestradiol in the endometrium.<ref name="pmid20004267" />

==Pharmacology==
The [[Chemistry:Pharmacodynamics|pharmacodynamics]] and [[Medicine:Pharmacokinetics|pharmacokinetics]] of estradiol in the context of use in birth control pills have been studied and reviewed.<ref name="pmid8240460">{{cite journal | vauthors = Kuhnz W, Gansau C, Mahler M | title = Pharmacokinetics of estradiol, free and total estrone, in young women following single intravenous and oral administration of 17β-estradiol | journal = Arzneimittelforschung | volume = 43 | issue = 9 | pages = 966–73 | date = September 1993 | issn = 0004-4172 | pmid = 8240460 }}</ref><ref name="pmid23375353" /><ref name="JensenBitzer2013">{{cite journal|last1=Jensen|first1=Jeffrey|last2=Bitzer|first2=Johannes|last3=Serrani|first3=Marco|title=Comparison of the pharmacologic and clinical profiles of new combined oral contraceptives containing estradiol|journal=Open Access Journal of Contraception|year=2013|pages=39|issn=1179-1527|doi=10.2147/OAJC.S50693|url=https://www.researchgate.net/publication/274274938|doi-access=free}}</ref>

==Research==
Experimental estradiol-containing birth control pills that were studied but never marketed include:<ref name="pmid20004267" />

* Estradiol/norethisterone (Netagen, Netagen 403)
* Estradiol/estriol/norethisterone (Netagen 423)
* Estradiol/estriol/norethisterone acetate
* Estradiol/desogestrel
* Estradiol cyclooctyl acetate/desogestrel
* Estradiol/ethinylestradiol/dienogest

A large [[Randomized controlled trial|randomized controlled trial]] of a birth control pill containing ethinylestradiol/norethisterone acetate versus a birth control pill containing estradiol/estriol/norethisterone acetate has been conducted.<ref name="pmid7428356">{{cite journal | title = A randomized, double-blind study of two combined oral contraceptives containing the same progestogen, but different estrogens. World Health Organization Task Force on Oral Contraception | journal = Contraception | volume = 21 | issue = 5 | pages = 445–59 | date = May 1980 | pmid = 7428356 | doi = 10.1016/0010-7824(80)90010-4 }}</ref>

==See also==
* Birth control pill formulations
* Estetrol/drospirenone

==References==
{{Reflist}}


{{Estradiol}}
{{Hormonal contraceptives}}
{{Estrogens and antiestrogens}}
{{Progestogens and antiprogestogens}}
{{Estrogen receptor modulators}}
{{Progesterone receptor modulators}}

[[Category:Estrogens]]
[[Category:Progestogens]]

{{Sourceattribution|Estradiol-containing birth control pill}}