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An update on new orally administered contraceptives for women

, MD

Bibliography

  • Winner B, Peipert JF, Zhao Q. Effectiveness of long-acting reversible contraception. N Engl J Med. 2012;366(21):1998–2007.
  • Committee on Adolescence. Contraception for adolescents. Pediatrics. 2014;134(4):e1244–e1256.
  • American College of Obstetricians and Gynecologists Committee on Gynecologic Practice; Long-Acting Reversible Contraception Working Group. ACOG Committee Opinion no. 450: increasing use of contraceptive implants and intrauterine devices to reduce unintended pregnancy. Obstet Gynecol. 2009;114(6):1434–1438.
  • Kuhl H. Pharmacology of estrogens and progestogens: influence of different routes of administration. Climacteric. 2005;8(Suppl 1):3–63.
  • Lidegaard Ø, Løkkegaard E, Svendsen AL, et al. Hormonal contraception and risk of venous thromboembolism: national follow-up study. BMJ. 2009;339(13):b2890.
  • Rott H. Contraception, venous thrombosis and biological plausibility. Minerva Med. 2013;104(2):161–167.
  • Rott H. Thrombotic risks of oral contraceptives. Curr Opin Obstet Gynecol. 2012;24(4):235–240.
  • Van Rooijen M, Silveira A, Hamsten A, et al. Sex hormone–binding globulin – a surrogate marker for the prothrombotic effects of combined oral contraceptives. Am J Obstet Gynecol. 2004;190(2):332–337.
  • Odlind V, Milsom I, Persson I, et al. Can changes in sex hormone binding globulin predict the risk of venous thromboembolism with combined oral contraceptive pills? Acta Obstet Gynecol Scand. 2002;81(6):482–490.
  • Grimes DA, Schulz KF, Raymond EG. Surrogate end points in women’s health research: science, protoscience, and pseudoscience. Fertil Steril. 2010;93(6):1731–1734.

*** A must read article for all clinicians to remind us what constitutes evidence that should change practice.

  • Chabbert-Buffet N, Gerris J, Jamin C, et al. Toward a new concept of “natural balance” in oral estroprogestin contraception. Gynecol Endocrinol. 2013;29(10):891–896.

** Well-written introduction of the potential of estradiol in oral contraceptives.

  • Fruzzetti F, Trémollieres F, Bitzer J. An overview of the development of combined oral contraceptives containing estradiol: focus on estradiol valerate/dienogest. Gynecol Endocrinol. 2012;28(5):400–408.
  • Ndefo UA, Mosely N. Estradiol valerate and estradiol valerate/dienogest (natazia) tablets: the first four-phasic oral contraceptive. P T. 2010;35(11):614–617.
  • World Health Organization Task Force on Oral Contraception. A randomized, double-blind study of two combined oral contraceptives containing the same progestogen, but different estrogens. Contraception. 1980;21(5):445–459.
  • Endrikat J, Parke S, Trummer D, et al. Ovulation inhibition with four variations of a four-phasic estradiol valerate/dienogest combined oral contraceptive: results of two prospective, randomized, open-label studies. Contraception. 2008;78(3) 218–225.
  • Gräser T, Römer T, Wiedey KD, et al. Climodien (estradiol valerate 2 mg plus dienogest 2 mg) is safe and effective in the treatment of postmenopausal complaints. Climacteric. 2001;4(4):332–342.
  • Von Schoultz B. Clinical efficacy and safety of combined estradiol valerate and dienogest: a new no-bleed treatment. Climacteric. 2003;6(Suppl 2):24–32.
  • Zimmerman T, Dietrich H, Wisser KH, et al. The efficacy and tolerability of Valette: A postmarketing surveillance study. Eur J contracept Reprod Health Care. 1999;4(3):155–164.
  • Sasagawa S, Shimizu Y, Kami H, et al. Dienogest is a selective progesterone receptor agonist in transactivation analysis with potent oral endometrial activity due to its efficient pharmacokinetic profile. Steroids. 2008;73(2):222–231.
  • Oettel M, Carol W, Gräser T, et al. Effect of ethinyl estradiol-dienogest combination on serum androgen concentrations. Zentralbl Gynakol. 1997;119(12):597–606.
  • Guida M, Bifulco G. Di Spiezio Sardo A, et al. Review of the safety, efficacy and patient acceptability of the combined dienogest/estradiol valerate contraceptive pill. Int J Womens Health. 2010;2:279–290.
  • Andres Mde P, Lopes LA, Baracat EC, et al. Dienogest in the treatment of endometriosis: systematic review. Arch Gynecol Obstet. 2015;292(3):523–529.
  • Ferrero S, Remorgida V, Venturini PL, et al. Endometriosis: the effects of dienogest. BMJ Clin Evid. 2015;pii:0802.
  • Strowitzki T, Faustmann T, Gerlinger C, et al. Safety and tolerability of dienogest in endometriosis: pooled analysis from the European clinical study program. Int J Womens Health. 2015;7:393–401.
  • Strowitzki T, Faustmann T, Gerlinger C, et al. Dienogest in the treatment of endometriosis-associated pelvic pain: a 12-week, randomized, double-blind, placebo-controlled study. Eur J Obstet Gynecol Reprod Biol. 2010;151(2):193–198.
  • Cosson M, Querleu D, Donnez J, et al. Dienogest is as effective as triptorelin in the treatment of endometriosis after laparoscopic surgery: results of a prospective, multicenter, randomized study. Fertil Steril. 2002;77(4):684–692.
  • Köhler G, Faustmann TA, Gerlinger C, et al. A dose-ranging study to determine the efficacy and safety of 1, 2, and 4mg of dienogest daily for endometriosis. Int J Gynaecol Obstet. 2010;108(1):21–25.
  • Strowitzki T, Marr J, Gerlinger C, et al. Dienogest is as effective as leuprolide acetate in treating the painful symptoms of endometriosis: a 24-week, randomized, multicentre, open-label trial. Hum Reprod. 2010;25(3):633–641.
  • Momoeda M, Harada T, Terakawa N, et al. Long-term use of dienogest for the treatment of endometriosis. J Obstet Gynaecol Res. 2009;35(6):1069–1076.
  • Takenaka M, Yano R, Hiraku Y, et al. Exploratory study of pre-surgical medications with dienogest or leuprorelin in laparoscopic cystectomy of endometrial cysts. J Obstet Gynaecol Res. 2015;41(8):1234–1239.
  • Angioni S, Nappi L, Pontis A, et al. Dienogest. A possible conservative approach in bladder endometriosis. Results of a pilot study. Gynecol Endocrinol. 2015;31(5):406–408.
  • Petraglia F, Hornung D, Seitz C, et al. Reduced pelvic pain in women with endometriosis: efficacy of long-term dienogest treatment. Arch Gynecol Obstet. 2012;285(1):167–173.
  • Agarwal S, Fraser MA, Chen I, et al. Dienogest for the treatment of deep endometriosis: case report and literature review. J Obstet Gynaecol Res. 2015;41(2):309–313.
  • Fawzy M, Mesbah Y. Comparison of dienogest versus triptorelin acetate in premenopausal women with adenomyosis: a prospective clinical trial. Arch Gynecol Obstet. 2015. [Epub ahead of print].
  • Morotti M, Sozzi F, Remorgida V, et al. Dienogest in women with persistent endometriosis-related pelvic pain during norethisterone acetate treatment. Eur J Obstet Gynecol Reprod Biol. 2014;183:188–192.
  • Tsuyoshi H, Orisaka M, Fukuda S, et al. Protective effect of dienogest on chemotherapy-induced reduced fertility in female rats. Steroids. 2015;93:1–7.
  • Kiley JW, Shulman LP. Estradial valerate and dienogest: a new approach to oral contraception. Int J Women’s Health. 2011;3:281–286.
  • Zeun S, Lu M, Uddin A, et al. Pharmacokinetics of an oral contraceptive containing oestradiol valerate and dienogest. Eur J Contracept Reprod Health Care. 2009;14(3):221–232.
  • Endrikat J, Parke S, Trummer D, et al. Pituitary, ovarian and additional contraceptive effects of an estradiol-based combined oral contraceptive: results of a randomized, open-label study. Contraception. 2013;87(2):227–234.
  • Mashchak CA, Lobo RA, Dozono-Takano R, et al. Comparison of pharmacodynamic properties of various estrogen formulations. Am J Obstet Gynecol. 1982;144(5):511–518.
  • Wiegratz I, Lee JH, Kutschera E, et al. Effect of four oral contraceptives on hemostatic parameters. Contraception. 2004;70(2):97–106.
  • Lindberg UB, Crona N, Stigendal L, et al. A comparison between effects of estradiol valerate and low dose ethinyl estradiol on haemostasis parameters. Thromb Haemost. 1989;61(1):65–69.
  • Oral Contraceptive and Hemostasis Study Group. The effects of seven monophasic oral contraceptive regimens on hemostatic variables: conclusions from a large randomized multicenter study. Contraception. 2003;67(3):173–185.
  • Lete I, Chabbert-Buffet N, Jamin C, et al. Haemostatic and metabolic impact of estradiol pills and drospirenone-containing ethinylestradiol pills vs. levonorgestrel-containing ethinylestradiol pills: A literature review. Eur J Contracept Reprod Health Care. 2015;20(5):329–343.
  • Klipping C, Duijkers I, Parke S, et al. Hemostatic effects of a novel estradiol-based oral contraceptive: an open-label, randomized, crossover study of estradiol valerate/dienogest versus ethinylestradiol/levonorgestrel. Drugs R D. 2011;11(2):159–170.
  • Junge W, Mellinger U, Parke S, et al. Metabolic and haemostatic effects of estradiol valerate/dienogest, a novel oral contraceptive: a randomized, open-label, single-centre study. Clin Drug Investig. 2011;31(8):573–584.
  • Pabinger I, Ay C. Biomarkers and venous thromboembolism. Arterioscler Thromb Vasc Biol. 2009;29(3):332–336.
  • Fleming TR, DeMets DL. Surrogate end points in clinical trials: are we being misled? Ann Intern Med. 1996;125(7):605–613.
  • Grandi G, Piancenti I, Volpe A, et al. Modification of body composition and metabolism during oral contraceptives containing non-androgenic progestins in association with estradiol or ethinyl estradiol. Gynecol Endocrinol. 2014;30(9):676–680.
  • De Leo V, Fruzzetti F, Musacchio MC, et al. Effect of a new oral contraceptive with estradiol valerate/dienogest on carbohydrate metabolism. Contraception. 2013;88(3):364–368.
  • Blode H, Zeun S, Parke S, et al. Evaluation of the effects of rifampicin, ketoconazole and erythromycin on the steady-state pharmacokinetics of the components of a novel oral contraceptive containing estradiol valerate and dienogest in healthy postmenopausal women. Contraception. 2012;86(4):337–344.
  • Bitzer J, Parke S, Roemer T, et al. Endometrial safety of an oral contraceptive Containing estradiol valerate and dienogest. Int J Womens Health. 2011;3:127–132.
  • Nelson A, Parke S, Makalova D, et al. Efficacy and bleeding profile of a combined oral contraceptive containing oestradiol valerate/dienogest: a pooled analysis of three studies conducted in North America and Europe. Eur J Contracept Reprod Health Care. 2013;18(4):264–273.
  • Nelson A, Parke S, Mellinger U, et al. Efficacy and safety of a combined oral contraceptive containing estradiol valerate/dienogest: results from a clinical study conducted in North America. J Womens Health (Larchmt). 2014;23(3):204–210.
  • Gerlinger C, Trussell J, Mellinger U, et al. Different Pearl Indices in studies of hormonal contraceptives in the United States: impact of study population. Contraception. 2014;90(2):142–146.
  • Trussell J, Portman D. The creeping Pearl: Why has the rate of contraceptive failure increased in clinical trials of combined hormonal contraceptive pills? Contraception. 2013;88(5):604–610.

*** Insightful article identifying the causes of the “Pearl creep” in more modern clinical times.

  • Ahrendt HJ, Makalová D, Parke S, et al. Bleeding pattern and cycle control with an estradiol-based oral contraceptive: a seven-cycle, randomized comparative trial of estradiol valerate/dienogest and ethinyl estradiol/levonorgestrel. Contraception. 2009;80(5):436–444.
  • Palacios S, Wildt L, Parke S, et al. Efficacy and safety of a novel oral contraceptive based on oestradiol (oestradiol valerate/dienogest): a Phase III trial. Eur J Obstet Gynecol Reprod Biol. 2010;149(1):57–62.
  • Fraser IS, Römer T, Parke S, et al. Effective treatment of heavy and/or prolonged menstrual bleeding with an oral contraceptive containing estradiol valerate and dienogest: a randomized, double-blind Phase III trial. Hum Reprod. 2011;26(10):2698–2708.
  • Fraser IS, Jensen J, Schaefers M, et al. Normalization of blood loss in women with heavy menstrual bleeding treated with an oral contraceptive containing estradiol valerate/dienogest. Contraception. 2012;86(2):96–101.
  • Jensen JT, Parke S, Mellinger U. et al. Effective treatment of heavy menstrual bleeding with estradiol valerate and dienogest: a randomized controlled trial. Obstet Gynecol. 2011;117(4):777–787.

* Well-written description of the impact of heavy menstrual bleeding and the studies done to test oral contraceptives as therapy.

  • Fraser IS, Parke S, Mellinger U, et al. Effective treatment of heavy and/or prolonged menstrual bleeding without organic cause: pooled analysis of two multinational, randomised, double-blind, placebo-controlled trials of oestradiol valerate and dienogest. Eur J Contracept Reprod Health Care. 2011;16(4):258–269.
  • Rafie S, Borgelt L, Koepf ER, et al. Novel oral contraceptive for heavy menstrual bleeding: estradiol valerate and dienogest. Int J Womens Health. 2013;5:313–321.

* Nice summary article.

  • Wasiak R, Filonenko A, Vanness DJ, et al. Impact of estradiol valerate/dienogest on work productivity and activities of daily living in women with heavy menstrual bleeding. J Womens Health (Larchmt). 2013;22(4):378–384.
  • Wasiak R, Filonenko A, Vanness DJ, et al. Impact of estradiol-valerate/dienogest on work productivity and activities of daily living in European and Australian women with heavy menstrual bleeding. Int J Womens Health. 2012;4:271–278.
  • Petraglia F, Parke S, Serrani M, et al. Estradiol valerate plus dienogest versus ethinylestradiol plus levonorgestrel for the treatment of primary dysmenorrhea. Int J Gynaecol Obstet. 2014;125(3):270–274.
  • Macìas G, Merki-Feld GS, Parke S, et al. Effects of a combined oral contraceptive containing oestradiol valerate/dienogest on hormone withdrawal-associated symptoms: results from the multicentre, randomised, double-blind, active-controlled HARMONY II study. J Obstet Gynaecol. 2013;33(6):591–596.
  • Jensen JT, Parke S, Mellinger U, et al. Hormone withdrawal-associated symptoms: comparison of oestradiol valerate/dienogest versus ethinylestradiol/norgestimate. Eur J Contracept Reprod Health Care. 2013;18(4):274–283.
  • Nappi RE, Terreno E, Sances G, et al. Effect of a contraceptive pill containing estradiol valerate and dienogest (E2V/DNG) in women with menstrually-related migraine (MRM). Contraception. 2013;88(3):369–375.
  • Davis SR, Bitzer J, Giraldi A, et al. Change to either a nonandrogenic or androgenic progestin-containing oral contraceptive preparation is associated with improved sexual function in women with oral contraceptive-associated sexual dysfunction. J Sex Med. 2013;10(12):3069–3079.
  • Grandi G, Xholli A, Napolitano A, et al. Pelvic pain and quality of life of women with endometriosis during quadriphasic estradiol valerate/dienogest oral contraceptive: a patient-preference prospective 24-week pilot study. Reprod Sci. 2015;22(5):626–632.
  • Stanczyk FZ. Pharmacokinetics and potency of progestins used for hormone replacement therapy and contraception. Rev Endocr Metab Disord. 2002;3(3):211–224.

* Classic study describing the multifaceted impacts of progestogens.

  • Ruan X, Seeger H, Mueck AO. The pharmacology of nomegestrol acetate. Maturitas. 2012;71(4):345–353.
  • Conard J, Basdevant A, Thomas JL, et al. Cardiovascular risk factors and combined estrogen-progestin replacement therapy: a placebo-controlled study with nomegestrol acetate and estradiol. Fertil Steril. 1995;64(5):957–962.
  • Coutinho EM, De Souza JC, Athayde C, et al. Multicenter clinical trial on the efficacy and acceptability of a single contraceptive implant of nomegestrol acetate, Uniplant. Contraception. 1996;53(2):121–125.
  • Van Diepen HA. Preclinical pharmacological profile of nomegestrol acetate, a synthetic 19-nor-progesterone derivative. Reprod Biol Endocrinol. 2012;8(10):85.
  • Gerrits MG, Schnabel PG, Post TM, et al. Pharmacokinetic profile of nomegestrol acetate and 17β-estradiol after multiple and single dosing in healthy women. Contraception. 2013;87(2):193–200.
  • Dinger J, Minh TD, Buttmann N, et al. Effectiveness of oral contraceptive pills in a large U.S. cohort comparing progestogen and regimen. Obstet Gynecol. 2011;117(1):33–40.
  • Lello S. Nomegestrol acetate: pharmacology, safety profile and therapeutic efficacy. Drugs. 2010;70(5):541–559.
  • Yang LP, Plosker GL. Nomegestrol acetate/estradiol: in oral contraception. Drugs. 2012;72(14):1917–1928.
  • Sitruk-Ware R, Nath A. Metabolic effects of contraceptive steroids. Rev Endocr Metab Disord. 2011;12(2):63–75.

* Excellent review of the topic.

  • Gerrits MG, Schnabel PG, Post TM, et al. Pharmacokinetic profile of nomegestrol acetate and 17β-estradiol after multiple and single dosing in healthy women. Contraception. 2013;87(2):193–200.
  • Chabbert-Buffet N, Chassard D, Ochsenbein E, et al. Inhibition of ovulation by NOMAC/E2, a novel monophasic oral contraceptive combining nomegestrol acetate and 17β-oestradiol: a double-blind, randomised, dose-finding pilot study. Eur J Contracept Reprod Health Care. 2011;16(2):76–84.
  • Christin-Maitre S, Serfaty D, Chabbert-Buffet N, et al. Comparison of a 24-day and a 21-day pill regimen for the novel combined oral contraceptive, nomegestrol acetate and 17β-stradiol (NOMAC/E2): a double-blind, randomized study. Hum Reprod. 2011;26(6):1338–1347.
  • Westhoff C, Kaunitz AM, Korver T, et al. Efficacy, safety, and tolerability of a monophasic oral contraceptive containing nomegestrol acetate and 17β-estradiol: a randomized controlled trial. Obstet Gynecol. 2012;119(5):989–999.

* Good summary of the US and Canadian clinical trial using modern criteria.

  • Mansour D, Verhoeven C, Sommer W, et al. Efficacy and tolerability of a monophasic combined oral contraceptive containing nomegestrol acetate and 17β-oestradiol in a 24/4 regimen, in comparison to an oral contraceptive containing ethinylestradiol and drospirenone in a 21/7 regimen. Eur J Contracept Reprod Health Care. 2011;16(6):430–443.
  • Ågren UM, Anttila M, Mäenpää-Liukko K, et al. Effects of a monophasic combined oral contraceptive containing nomegestrol acetate and 17β-oestradiol compared with one containing levonorgestrel and ethinylestradiol on haemostasis, lipids and carbohydrate metabolism. Eur J Contracept Reprod Health Care. 2011;16(6):444–457.
  • Ågren UM, Anttila M, Mäenpää-Liukko K, et al. Effects of a monophasic combined oral contraceptive containing nomegestrol acetate and 17β-oestradiol in comparison to one containing levonorgestrel and ethinylestradiol on markers of endocrine function. Eur J Contracept Reprod Health Care. 2011;16(6):458–467.
  • Sørdal T, Grob P, Verhoeven C. Effects on bone mineral density of a monophasic combined oral contraceptive containing nomegestrol acetate/17β-estradiol in comparison to levonorgestrel/ethinylestradiol. Acta Obstet Gynecol Scand. 2012;91(11):1279–1285.
  • Gaussem P, Alhenc-Gelas M, Jl T, et al. Haemostatic effects of a new combined oral contraceptive, nomegestrol acetate/17β-estradiol, compared with those of evonorgestrel/ethinyl estradiol. A double-blind, randomised study. Thromb Haemost. 2011;105(3):560–567.

* Important initial study of the potential for reduced VTE risk with E2.

  • Duijkers IJ, Klipping C, Grob P, et al. Effects of a monophasic combined oral contraceptive containing nomegestrol acetate and 17 beta-oestradiol on ovarian function in comparison to a monophasic combined oral contraceptive containing drospirenone and ethinylestradiol. Eur J Contracept Reprod Health Care. 2010;15(5):314–325.
  • Witjes H, Creinin MD, Sundström-Poromaa I, et al. Comparative analysis of the effects of nomegestrol acetate/17 β-estradiol and drospirenone/ethinylestradiol on premenstrual and menstrual symptoms and dysmenorrhea. Eur J Contracept Reprod Health Care. 2015;20(4):296–307.
  • Sulak PJ, Scow RD, Preece C, et al. Hormone withdrawal symptoms in oral contraceptive users. Obstet Gynecol. 2000;95(2):261–266.

** Classic study demonstrating the suffering women have with scheduled bleeding with oral contraceptives.

  • Sulak P, Willis S, Kuehl T, et al. Headaches and oral contraceptives: impact of eliminating the standard 7-day placebo interval. Headache. 2007;47(1):27–37.
  • Sulak PJ, Kuehl TJ, Coffee A, et al. Prospective analysis of occurrence and management of breakthrough bleeding during an extended oral contraceptive regimen. Am J Obstet Gynecol. 2006;195(4):935–941.
  • Coutinho EM, Segal SJIS. Is menstruation obsolete? New York (NY): Oxford University Press; 1999.

*** A must read for anyone in women’s health. This should be the basis for all conversations with women.

  • Edelman A, Lew R, Cwiak C, et al. Acceptability of contraceptive-induced amenorrhea in a racially diverse group of US women. Contraception. 2007;75(6):450–453.

* Provides good insights into the beliefs 9and knowledge gaps) women hold.

  • Sulak PJ. Ovulation suppression of premenstrual symptoms using oral contraceptives. Am J Manag Care. 2005;11(16 Suppl):S492–7.
  • Snow R, Hardy E, Kneuper E, et al. Women’s responses to menses and nonbleeding intervals in the USA, Brazil and Germany. Contraception. 2007;76(1):23–29.
  • Andrist LC, Arias RD, Nucatola D, et al. Women’s and providers’ attitudes toward menstrual suppression with extended use of oral contraceptives. Contraception. 2004;70(5):359–363.
  • Szarewski A, Von Stenglin A, Rybowski S. Women’s attitudes towards monthly bleeding: results of a global population-based survey. Eur J Contracept Reprod Health Care. 2012;17(4):270–283.
  • Kaunitz AM, Portman DJ, Hait H, et al. Adding low-dose estrogen to the hormone-free interval: impact on bleeding patterns in users of a 91-day extended regimen oral contraceptive. Contraception. 2009;79(5):350–355.
  • Reape KZ, DiLiberti CE, Hendy CH, et al. Effects on serum hormone levels of low-dose estrogen in place of placebo during the hormone-free interval of an oral contraceptive. Contraception. 2008;77(1):34–39.
  • Anderson FD, Feldman R, Reape KZ. Endometrial effects of a 91-day extended-regimen oral contraceptive with low-dose estrogen in place of placebo. Contraception. 2008;77(2):91–96.
  • Kroll R, Reape KZ, Margolis M. The efficacy and safety of a low-dose, 91-day, extended-regimen oral contraceptive with continuous ethinyl estradiol. Contraception. 2010;81(1):41–48.
  • Anderson FD, Hait H. A multicenter, randomized study of an extended cycle oral contraceptive. Contraception. 2003;68(2):89–96.
  • Jensen JT, Garie SG, Trummer D, et al. Bleeding profile of a flexible extended regimen of ethinylestradiol/drospirenone in US women: an open-label, three-arm, active-controlled, multicenter study. Contraception. 2012;86(2):110–118.
  • Darwish M, Bond M, Ricciotti N, et al. A comparison of the pharmacokinetic profile of an ascending-dose, extended-regimen combined oral contraceptive to those of other extended regimens. Reprod Sci. 2014;21(11):1401–1410.
  • Portman DJ, Kaunitz AM, Howard B, et al. Efficacy and safety of an ascending-dose, extended-regimen levonorgestrel/ethinyl estradiol combined oral contraceptive. Contraception. 2014;89(4):299–306.
  • Klipping C, Duijkers I, Fortier MP, et al. Long-term tolerability of ethinylestradiol 20 μg/drospirenone 3 mg in a flexible extended regimen: results from a randomised, controlled, multicentre study. J Fam Plann Reprod Health Care. 2012;38(2):84–93.
  • Klipping C, Duijkers I, Fortier MP, et al. Contraceptive efficacy and tolerability of ethinylestradiol 20 μg/drospirenone 3 mg in a flexible extended regimen: an open-label, multicentre, randomised, controlled study. J Fam Plann Reprod Health Care. 2012;38(2):73–83.
  • Strowitzki T, Kirsch B, Elliesen J. Efficacy of ethinylestradiol 20 μg/drospirenone 3 mg in a flexible extended regimen in women with moderate-to-severe primary dysmenorrhoea: an open-label, multicentre, randomised, controlled study. J Fam Plann Reprod Health Care. 2012;38(2):94–101.
  • Grimes DA, Schulz KF. Nonspecific side effects of oral contraceptives: nocebo or noise? Contraception. 2011;83(1):5–9.
  • Quartette: an ascending-dose, extended-cycle oral contraceptive. Med Lett Drugs Ther. 2013;55(1420):54–55.

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