The safety and contraceptive efficacy of a 24-day low-dose oral contraceptive regimen containing gestodene 60 microg and ethinylestradiol 15 microg.
OBJECTIVE
The safety and contraceptive efficacy of a new 24-day regimen of an oral contraceptive combination containing gestodene (GTD) 60 microg and ethinylestradiol (EE) 15 microg was evaluated in an open-label, multicenter study.


METHODS
Adult women received GTD 60 microg/EE 15 microg from day 1 to 24 and 4 days of placebo during a 28-day cycle for either 13 or 19 cycles.


RESULTS
Of the 1515 subjects enrolled, 1496 were included in the intent-to-treat analysis. A total of three pregnancies were reported during the 18 194 treatment cycles of the study, yielding a Pearl index of 0.21. Life-table analysis, based on 16 954 cycles, gave an accidental pregnancy rate of 0.0033. The most frequent adverse events were headache (reported in 35% of subjects), absence of bleeding (16%), flu-like syndrome (15%), pharyngitis (15%) and abdominal pain (15%). The most frequent reasons for withdrawal from the study were metrorrhagia, flu syndrome and absence of bleeding. Analyses of withdrawal and intermenstrual bleeding and spotting indicated acceptable cycle control.


CONCLUSIONS
The 24-day GTD 60 microg/EE 15 microg regimen appears to be a well-tolerated and effective method for low-dose oral contraception. The current formulation offers an ultra-low steroidal dosage combined with a reduced pill-free interval to improve contraceptive efficacy.
D000328:Adult; D003276:Contraceptives, Oral / Q000009:adverse effects / Q000494:pharmacology*; D003277:Contraceptives, Oral, Combined / Q000009:adverse effects / Q000494:pharmacology*; D003280:Contraceptives, Oral, Synthetic / Q000008:administration & dosage / Q000009:adverse effects; D004334:Drug Administration Schedule; D004967:Estrogens / Q000009:adverse effects / Q000494:pharmacology*; D004997:Ethinyl Estradiol / Q000009:adverse effects / Q000494:pharmacology*; D005260:Female; D006801:Humans; D008597:Menstrual Cycle / Q000187:drug effects; D009652:Norpregnenes / Q000009:adverse effects / Q000494:pharmacology*; D011247:Pregnancy
D003276:Contraceptives, Oral; D003277:Contraceptives, Oral, Combined; D003280:Contraceptives, Oral, Synthetic; D004967:Estrogens; D009652:Norpregnenes; C033273:Gestodene; D004997:Ethinyl Estradiol