Research in the area of oral contraception currently focuses on the development of selective progestogens that combine targeted progestational and antiovulatory activity with a minimal potential for androgenicity. The present dual-center study was conducted to investigate the efficacy, tolerability, and safety of a new monophasic oral contraceptive (OC) containing 250 micrograms norgestimate in combination with 35 micrograms ethinyl estradiol (Ortho-Cyclen or Cilest). Ninety-seven healthy women of childbearing age participated in the study: 37 received the new norgestimate/ethinyl estradiol combination OC as primary therapy and 31 were switched over from other OCs. The norgestimate/ethinyl estradiol formulation was well tolerated and was associated with excellent cycle control. After six cycles of use, there were no statistically significant differences in the incidence of spotting or breakthrough bleeding compared with baseline, nor were there any significant changes in the incidence of headache, nausea, or mastalgia. Body weights remained constant for the duration of the study, as did systolic and diastolic blood pressures. Of particular note was the absence of any statistically significant alterations in metabolic parameters, including blood glucose or lipoprotein levels. These findings are consistent with the results of several other European studies and indicate that the norgestimate/ethinyl estradiol combination OC combines superior cycle control with minimal risk of androgenic side effects.