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 Dec;16(6):430-43. doi: 10.3109/13625187.2011.614029. Epub 2011 Oct 13.


Objectives: The primary objective was to assess the efficacy, cycle control and tolerability of a monophasic combined oral contraceptive (COC) containing nomegestrol acetate (NOMAC) and 17β-oestradiol (E2). Effects on acne were evaluated as a secondary objective. Results were compared to those of a COC containing drospirenone (DRSP) and ethinylestradiol (EE).

Methods: Women (aged 18-50 years) were randomised to receive NOMAC/E2 (2.5 mg/1.5 mg) in a 24/4-day regimen (n=1591) or DRSP/EE (3 mg/30 μg) in a 21/7-day regimen (n=535) for 13 cycles.

Results: Estimated Pearl Indices for NOMAC/E2 and DRSP/EE were 0.38 and 0.81 in women aged≤35 years and 0.31 and 0.66 for all women (18-50 years), respectively. Scheduled withdrawal bleedings were shorter and lighter among users of NOMAC/E2 and were sometimes absent altogether. Intracyclic bleeding/spotting was infrequent in both groups, and decreased over time. Type and frequency of adverse events were similar to those typically reported for COCs.

Conclusions: These data show that NOMAC/E2 provides high contraceptive efficacy with acceptable cycle control as well as an overall adverse event profile similar to that of DRSP/EE.

Publication types

  • Comparative Study
  • Multicenter Study
  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Acne Vulgaris / drug therapy
  • Adolescent
  • Adult
  • Androstenes / adverse effects
  • Androstenes / therapeutic use
  • Contraceptives, Oral, Combined / adverse effects*
  • Contraceptives, Oral, Combined / therapeutic use*
  • Contraceptives, Oral, Synthetic / adverse effects
  • Contraceptives, Oral, Synthetic / therapeutic use
  • Estradiol / adverse effects
  • Estradiol / therapeutic use
  • Estrogens / adverse effects
  • Estrogens / therapeutic use
  • Ethinyl Estradiol / adverse effects
  • Ethinyl Estradiol / therapeutic use
  • Female
  • Humans
  • Megestrol / adverse effects
  • Megestrol / therapeutic use
  • Menstrual Cycle / drug effects
  • Metrorrhagia / chemically induced*
  • Middle Aged
  • Mineralocorticoid Receptor Antagonists / adverse effects
  • Mineralocorticoid Receptor Antagonists / therapeutic use
  • Norpregnadienes / adverse effects
  • Norpregnadienes / therapeutic use
  • Pregnancy
  • Pregnancy Rate
  • Substance Withdrawal Syndrome*
  • Young Adult


  • Androstenes
  • Contraceptives, Oral, Combined
  • Contraceptives, Oral, Synthetic
  • Estrogens
  • Mineralocorticoid Receptor Antagonists
  • Norpregnadienes
  • Ethinyl Estradiol
  • Estradiol
  • nomegestrol acetate
  • Megestrol
  • drospirenone