Comparison of a novel norgestimate/ethinyl estradiol oral contraceptive (Ortho Tri-Cyclen Lo) with the oral contraceptive Loestrin Fe 1/20

This multicenter study compared the contraceptive efficacy, cycle control, and safety of a new triphasic norgestimate (180/215/250 mug)/ethinyl estrad iol 25 mug regimen (Ortho Tri-Cyclen Lo) (n = 1,723) with that of norethind rone acetate 1 mg/ethinyl estradiol 20 mug (Loestrin Fe 1/20) (n = 1,171). Healthy women were treated for up to 13 cycles. Demographics were similar b etween regimens. Contraceptive efficacy was comparable for Ortho Tri-Cyclen Lo and Loestrin Fe 1/20. The overall and method failure probabilities of p regnancy through 13 cycles were 1.9% and 1.5%, respectively, with Ortho Tri -Cyclen Lo and 2.6% and 2.4%, respectively, with Loestrin Fe 1/20. Breakthr ough bleeding and spotting was reported by a significantly lower percentage of participants in the Ortho Tri-Cyclen Lo group compared with the Loestri n Fe 1/20 group. At representative Cycles 1, 3, 6, 9, and 13, breakthrough bleeding and spotting rates were 16.3, 11.5, 10.3, 7.9, and 7.7%, respectiv ely, in the Ortho Tri-Cyclen Lo group and 34.9, 22.9, 22.2, 15.9, and 13.1% , respectively, in the Loestrin Fe 1/20 group. Compliance and safety data w ere similar for the two regimens. (C) 2001 Elsevier Science Inc. All rights reserved.