Birth control pill formulations

Birth control pills come in a variety of formulations. The main division is between combined oral contraceptive pills, containing both estrogens and synthetic progestogens (progestins), and progestogen only pills. Combined oral contraceptive pills also come in varying types, including varying doses of estrogen, and whether the dose of estrogen or progestogen changes from week to week.

Mechanism of action

Combination pills usually work by preventing the ovaries from releasing eggs (ovulation). They also thicken the cervical mucus, which keeps sperm from penetrating into the uterus and joining with an egg. The hormones in combination and progestogen-only pills also thin the lining of the uterus. This could prevent pregnancy by interfering with implantation of a blastocyst.

Main action in typical use is prevention of ovulation.

Combined oral contraceptive pills

All contain an estrogen, ethinylestradiol or mestranol,^[1]^[2] in varying amounts, and one of a number of different progestogens. (Regarding the estrogen, the inactive 3-methyl ether of ethinylestradiol, which must be metabolized by the liver into the active ethinylestradiol; 50 μみゅーg of mestranol is equivalent to only 35 μみゅーg of ethinylestradiol and should not be used when high-dose [50 μみゅーg ethinylestradiol] estrogen pills are needed; mestranol was the estrogen used in the first oral contraceptive, Enovid). They are usually taken for 21 days with then a seven-day gap during which a withdrawal bleed (often, but incorrectly, referred to as a menstrual period) occurs. These differ in the amount of estrogen given, and whether they are monophasic (the same dose of estrogen and progestogen during each of the 21 days) or multiphasic (varying doses). The introduction of extended-cycle monophasic pills (i.e. Seasonale) has shown that the withdrawal bleeding intervals can be decreased.

Monophasic

These are typically given as 21 tablets of estrogen and progestogen, followed by seven tablets of placebo or an iron supplement,^[3]^[4] although some newer formulations contain more active tablets and fewer placebos. Everyday regimens (Microgynon 30 ED, Femodene ED, Logynon ED), which include seven inactive placebo pills, are rarely used in UK practice.^[5] Different formulations contain different amounts of estrogen and progestogen:

15 μみゅーg ethinylestradiol
- 60 μみゅーg gestodene: 24 days + 4 days placebo (Spain: Melodene-15; Israel: Minesse)^[6]
20 μみゅーg ethinylestradiol
- 1000 μみゅーg norethisterone acetate (UK: Loestrin 20, Galen; US: Loestrin 1/20, Duramed; Microgestin 1/20, Watson Pharmaceuticals; Junel 1/20, Barr)
- 1000 μみゅーg norethisterone acetate: 24 days + 4 days ferrous fumarate only (US: Loestrin 24 Fe, Warner Chilcott)
- 90 μみゅーg levonorgestrel: continuous: 365 days/year, no placebo (US: Amethyst, Watson)
- 100 μみゅーg levonorgestrel: extended cycle: 84 days + 7 days 10 μみゅーg ethinylestradiol only (US: LoSeasonique, Teva; CamreseLo, Teva)
- 100 μみゅーg levonorgestrel (US: Alesse, Wyeth; Aviane, Barr; Lessina, Barr; Lutera, Watson; Sronyx, Watson)
- 150 μみゅーg desogestrel (UK: Mercilon, Organon; HU: Novynette, Richter Gedeon)
- 75 μみゅーg gestodene (UK: Femodette, Bayer; RU: Logest, Bayer; Brazil: Femiane, Bayer^[7])
- 3000 μみゅーg drospirenone: 24 days + 4 days placebo (US, EU, RU: Yaz; Bayer Schering Pharma AG. Cleonita); 21 days + 7 days placebo (US, EU: Yasminelle, Bayer); 24 days + 4 days placebo and levomefolate calcium (US: Beyaz; Bayer)
30 μみゅーg ethinylestradiol
- 1500 μみゅーg norethisterone acetate (UK: Loestrin 30, Galen; US: Loestrin 1.5/30, Duramed; Microgestin 1.5/30, Watson; Junel 1.5/30, Barr)
- 300 μみゅーg norgestrel (US: Lo/Ovral, Wyeth; Low-Ogestrel, Watson; Cryselle, Barr)
- 150 μみゅーg levonorgestrel (UK: Ovranette, Wyeth; Microgynon 30, Microgynon 30 ED, Bayer; US: Nordette, Duramed, Levora, Watson, Portia, Barr)
- 150 μみゅーg levonorgestrel: 21 day cycle + 7 days no pills (Canada: Min-Ovral 21; EU: Ovoplex 150/30; Sweden: Neovletta, Prionelle)
- 150 μみゅーg levonorgestrel: 21 day cycle + 7 days placebo (Canada: Min-Ovral 28; Sweden: Prionelle 28; RU: Rigevidon 21+7, Richter Gedeon)
- 150 μみゅーg levonorgestrel: extended cycle: 84 days + 7 days placebo (US: Seasonale, Duramed; Quasense, Watson; Jolessa, Barr, Introvale)
- 150 μみゅーg levonorgestrel: extended cycle: 84 days + 7 days 10 μみゅーg ethinylestradiol only (US: Seasonique, Duramed; Camrese, Teva; Amethia, Watson)
- 75 μみゅーg gestodene (UK: Femodene, Femodene ED, Bayer; Minulet, Wyeth; RU: Femoden, Jenapharm)
- 150 μみゅーg desogestrel (AUえーゆー, EU, RU, UK: Marvelon, BR: Microdiol, US: Desogen, MSD; US: Ortho-Cept, Ortho-McNeil; RU: Regulon, Richter Gedeon)
- 3000 μみゅーg drospirenone (AUえーゆー, EU, US: Yasmin, FR: Jasmine, RU: Yarina, Bayer Schering Pharma AG); with levomefolate calcium (US: Safyral, Bayer Schering Pharma AG)
- 2000 μみゅーg chlormadinone acetate (EU: Belara, Benelux: Bellina; Gedeon Richter)
- 2000 μみゅーg dienogest (AUえーゆー, EU: Valette, RU: Jeanine, Bayer Schering Pharma AG; RU: Siluet, Gedeon Richter)
35 μみゅーg ethinylestradiol
- 400 μみゅーg norethisterone: chewable, spearmint flavor (US: Femcon Fe, Warner Chilcott)
- 400 μみゅーg norethisterone (US: Ovcon 35, Warner Chilcott; Balziva, Barr)
- 500 μみゅーg norethisterone (UK: Ovysmen, Janssen-Cilag; Brevinor, Pfizer; US: Modicon, Ortho-McNeil; Brevicon, Watson; Nortrel 0.5/35, Barr)
- 1000 μみゅーg norethisterone (AUえーゆー, CAN: Synphasic, Pfizer; UK: Norimin, Pfizer; US: Ortho-Novum 1/35, Ortho-McNeil; Norinyl 1/35, Watson; Necon, Watson; Nortrel 1/35, Barr)
- 1000 μみゅーg etynodiol diacetate (US: Demulen 1/35, Pfizer; Zovia 1/35, Watson; Kelnor, Barr)
- 250 μみゅーg norgestimate (UK: Cilest, Janssen-Cilag; US: Ortho Cyclen, Ortho-McNeil; MonoNessa, Watson; Sprintec, Barr; Sweden: Amorest^[8])
- 2000 μみゅーg cyproterone acetate: only approved for severe acne or severe hirsutism in the UK (AUえーゆー, RU: Diane-35, UK: Dianette, Bayer)
50 μみゅーg mestranol (equivalent to 35 μみゅーg ethinylestradiol)
- 1000 μみゅーg norethisterone (UK: Norinyl-1, Pfizer; US: Ortho-Novum 1/50; Ortho-McNeil; Norinyl 1/50, Watson; Necon 1/50, Watson)
50 μみゅーg ethinylestradiol
- 1000 μみゅーg norethisterone (US: Ovcon 50, Warner Chilcott)
- 1000 μみゅーg etynodiol diacetate (US: Demulen 1/50, Pfizer; Zovia 1/50, Watson)
- 500 μみゅーg norgestrel (US: Ogestrel, Watson)
- 250 μみゅーg levonorgestrel (US: Nordiol, Wyeth)
1.5 mg estradiol (as hemihydrate)
- 2.5 mg nomegestrol acetate: 24-day cycle + 4 placebo pills (AUえーゆー, EU, RU: Zoely, MSD)
15 mg estetrol monohydrate (equivalent to 14.2 mg estetrol)
- 3 mg drospirenone: 24-day cycle + 4 inactive pills (US, CAN: Nexstellis, Mayne, EU: Drovelis, Gedeon Richter Plc., EU: Lydisilka, Estetra SRL)

Multiphasic

25 μみゅーg ethinylestradiol: triphasic
- ethinylestradiol/norgestimate combination with 7 tablets 25 μみゅーg/180 μみゅーg, 7 tablets 25 μみゅーg/215 μみゅーg, 7 tablets 25 μみゅーg/250 μみゅーg followed by 7 placebos (Ortho Tri-Cyclen Lo from Ortho-McNeil, Tri-Lo Sprintec back from Teva, Tri-Lo Marzia from Lupin, and norgestimate/ethinylestradiol from Mylan)^[9]
- ethinylestradiol/desogestrel combination with 7 tablets 25 μみゅーg/100 μみゅーg, 7 tablets 25 μみゅーg/125 μみゅーg, 7 tablets 25 μみゅーg/150 μみゅーg, followed by 7 tablets of ferric oxide (US: Cyclessa, Organon; Velivet, Barr)
20/30/35 μみゅーg ethinylestradiol: estrophasic
- ethinylestradiol/norethisterone acetate combination with 5 tablets 20 μみゅーg/1000 μみゅーg, 7 tablets 30 μみゅーg/1000 μみゅーg, 9 tablets 35 μみゅーg/1000 μみゅーg, followed by 7 tablets of ferrous fumarate 75 mg (US: Estrostep Fe, Warner Chilcott)
35/30/30 μみゅーg ethinylestradiol: triphasic
- ethinylestradiol/desogestrel combination with 7 tablets 35 μみゅーg/50 μみゅーg, 7 tablets 30 μみゅーg/100 μみゅーg, 7 tablets 30 μみゅーg/150 μみゅーg (RU: Tri-Merci, Organon)
30/40/30 μみゅーg ethinylestradiol: triphasic
- ethinylestradiol/levonorgestrel combination with 6 tablets 30 μみゅーg/50 μみゅーg, 5 tablets 40 μみゅーg/75 μみゅーg, 10 tablets 30 μみゅーg/125 μみゅーg (UK: Trinordiol, Wyeth; Logynon, Logynon ED, Bayer; US: Triphasil, Wyeth; Trivora, Watson; Enpresse, Barr)
- ethinylestradiol/gestodene combination with 6 tablets 30 μみゅーg/50 μみゅーg, 5 tablets 40 μみゅーg/70 μみゅーg, 10 tablets 30 μみゅーg/100 μみゅーg (UK: Triadene, Bayer; Tri-Minulet, Wyeth)
35 μみゅーg ethinylestradiol: triphasic
- ethinylestradiol/norethisterone combination with 7 tablets 35 μみゅーg/500 μみゅーg, 9 tablets 35 μみゅーg/1000 μみゅーg, 5 tablets 35 μみゅーg/500 μみゅーg (UK: Synphase, Pfizer; US: Tri-Norinyl, Watson; Leena, Watson)
- ethinylestradiol/norethisterone combination with 7 tablets 35 μみゅーg/500 μみゅーg, 7 tablets 35 μみゅーg/750 μみゅーg, 7 tablets 35 μみゅーg/1000 μみゅーg (UK: TriNovum, Janssen-Cilag; US: Ortho-Novum 7/7/7, Ortho-McNeil; Necon 7/7/7, Watson; Nortrel 7/7/7, Barr)
- ethinylestradiol/norgestimate combination with 7 tablets 35 μみゅーg/180 μみゅーg, 7 tablets 35 μみゅーg/215 μみゅーg, 7 tablets 35 μみゅーg/250 μみゅーg followed by 7 placebos (Ortho Tri-Cyclen, Ortho-McNeil; TriNessa, Watson; Tri-Sprintec, Barr)
35 μみゅーg ethinylestradiol: biphasic
- ethinylestradiol/norethisterone combination with 10 tablets 35 μみゅーg/500 μみゅーg, 11 tablets 35 μみゅーg/1000 μみゅーg, followed by 7 placebos (US: Ortho-Novum 10/11, Ortho-McNeil; Necon 10/11, Watson)
- ethinylestradiol/norethisterone combination with 7 tablets 35 μみゅーg/500 μみゅーg, 14 tablets 35 μみゅーg/1000 μみゅーg (UK: BiNovum, Janssen-Cilag)

3/2/1 mg estradiol valerate: estrophasic
- estradiol valerate/dienogest combination with 2 tablets 3 mg/0 mg, followed by 5 tablets 2 mg/2 mg, 17 tablets 2 mg/3 mg, 2 tablets 1 mg/0 mg, and 2 placebos. (AUえーゆー, EU, RU: Qlaira, US: Natazia, Bayer)^[10]^[11]

Progestogen-only pills

Progestogen-only pills (POPs) use a progestogen alone with doses taken continuously and no or a short gap between packs taken. People who use them may experience irregular light bleeds, and whilst irregular in the first few months of taking, usually settles to a regular pattern in time.

The following progestogens are used:

350 μみゅーg norethisterone (norethindrone) (UK: Micronor, Janssen-Cilag; Noriday, Pfizer; US: Micronor, Ortho-McNeil; Nor-QD, Watson; Nora-BE, Watson; Jolivette, Watson; Camila, Barr; Errin, Barr; Heather, Glenmark; RU: Primolut-Nor, Bayer; Norkolut, Richter Gedeon)
4 mg drospirenone (Slynd)
75 μみゅーg desogestrel (UK: Cerazette, Loestrin; RU: Cerazette, Organon; Lactinette, Richter Gedeon; SE: Gestrina)
30 μみゅーg levonorgestrel (UK: Norgeston, Bayer; AUS, RU: Microlut, Bayer)
500 μみゅーg etynodiol diacetate (UK: Femulen, Pfizer)
500 μみゅーg lynestrenol (RU: Exluton, Organon)
75 μみゅーg norgestrel (US: Opill, Perrigo)

Contraindications

Generally oral contraceptives should not be used in people who currently have the following conditions:

Thrombophlebitis or thromboembolic disorders
A history of deep vein thrombophlebitis or thromboembolic disorders
Cerebrovascular or coronary artery disease (current or history)
Valvular heart disease with thrombogenic complications
Severe hypertension
Diabetes with vascular involvement
Headaches with focal neurological symptoms
Major surgery with prolonged immobilization
Known or suspected carcinoma of the breast or personal history of breast cancer
Carcinoma of the endometrium or other known or suspected estrogen-dependent neoplasia
Undiagnosed abnormal genital bleeding
Cholestatic jaundice of pregnancy or jaundice with prior pill use
Hepatic adenomas or carcinomas, or active liver disease
Known or suspected pregnancy
Hypersensitivity to any component of the product

More comprehensive guidelines that include analysis of risks and benefits can be found in the World Health Organization Medical Eligibility for Contraceptive Use Guidelines^[12] which are reflected in the CDC Medical Eligibility for Contraceptive Use Guidelines.^[13]

References

^ Hatcher, Robert A.; Nelson, Anita (2004). "Combined Hormonal Contraceptive Methods". In Hatcher; Robert A. (eds.). Contraceptive Technology (18th rev. ed.). New York: Ardent Media. pp. 391–460. ISBN 0-9664902-5-8.
^ Speroff, Leon; Darney, Philip D. (2005). "Oral Contraception". A Clinical Guide for Contraception (4th ed.). Philadelphia: Lippincott Williams & Wilkins. pp. 21–138. ISBN 0-7817-6488-2.
^ "US Patent:Oral contraceptive:Patent 6451778 Issued on September 17, 2002 Estimated Expiration Date: July 2, 2017". PatentStorm LLC. Archived from the original on June 13, 2011. Retrieved 2010-11-19.
^ Serge Herceberg; Paul Preziosi; Pilar Galan. "Iron deficiency in Europe" (PDF). Public Health Nutrition: 4(2B). pp. 537–545. Archived from the original (PDF) on 2011-07-26. Retrieved 2010-11-19.
^ FFPRHC (2007). "Clinical Guidance: First Prescription of Combined Oral Contraception" (PDF). Archived from the original (PDF) on 2007-07-04. Retrieved 2007-07-07.
^ "Archived copy" (PDF). Archived from the original (PDF) on 2011-07-22. Retrieved 2011-04-20.{{cite web}}: CS1 maint: archived copy as title (link)
^ "Archived copy" (PDF). Archived from the original (PDF) on 2015-05-03. Retrieved 2014-11-29.{{cite web}}: CS1 maint: archived copy as title (link)
^ "Amorest 28". FASS.se. Retrieved 2019-08-08.
^ "GoodRx - Error". Retrieved 31 August 2016.
^ "Natazia Prescribing Information" (PDF). Archived from the original (PDF) on 2011-10-05. Retrieved 2011-12-01.
^ "Summary of Product Characteristics for Qlaira". Archived from the original on 2009-12-26. Retrieved 2009-12-29.
^ "Medical eligibility criteria for contraceptive use". World Health Organization. Retrieved 2016-03-11.
^ "United States Medical Eligibility Criteria (USMEC) for Contraceptive Use | Unintended Pregnancy | Reproductive Health | CDC". www.cdc.gov. Retrieved 2016-03-11.

[hatcher-1] Hatcher, Robert A.; Nelson, Anita (2004). "Combined Hormonal Contraceptive Methods". In Hatcher; Robert A. (eds.). Contraceptive Technology (18th rev. ed.). New York: Ardent Media. pp. 391–460. ISBN 0-9664902-5-8.

[speroff-2] Speroff, Leon; Darney, Philip D. (2005). "Oral Contraception". A Clinical Guide for Contraception (4th ed.). Philadelphia: Lippincott Williams & Wilkins. pp. 21–138. ISBN 0-7817-6488-2.

[3] "US Patent:Oral contraceptive:Patent 6451778 Issued on September 17, 2002 Estimated Expiration Date: July 2, 2017". PatentStorm LLC. Archived from the original on June 13, 2011. Retrieved 2010-11-19.

[4] Serge Herceberg; Paul Preziosi; Pilar Galan. "Iron deficiency in Europe" (PDF). Public Health Nutrition: 4(2B). pp. 537–545. Archived from the original (PDF) on 2011-07-26. Retrieved 2010-11-19.

[first_prescription-5] FFPRHC (2007). "Clinical Guidance: First Prescription of Combined Oral Contraception" (PDF). Archived from the original (PDF) on 2007-07-04. Retrieved 2007-07-07.

[6] "Archived copy" (PDF). Archived from the original (PDF) on 2011-07-22. Retrieved 2011-04-20.{{cite web}}: CS1 maint: archived copy as title (link)

[7] "Archived copy" (PDF). Archived from the original (PDF) on 2015-05-03. Retrieved 2014-11-29.{{cite web}}: CS1 maint: archived copy as title (link)

[8] "Amorest 28". FASS.se. Retrieved 2019-08-08.

[9] "GoodRx - Error". Retrieved 31 August 2016.

[10] "Natazia Prescribing Information" (PDF). Archived from the original (PDF) on 2011-10-05. Retrieved 2011-12-01.

[11] "Summary of Product Characteristics for Qlaira". Archived from the original on 2009-12-26. Retrieved 2009-12-29.

[12] "Medical eligibility criteria for contraceptive use". World Health Organization. Retrieved 2016-03-11.

[13] "United States Medical Eligibility Criteria (USMEC) for Contraceptive Use | Unintended Pregnancy | Reproductive Health | CDC". www.cdc.gov. Retrieved 2016-03-11.

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