The purpose of this study is to determine whether NEA TDS is effective in the prevention of pregnancy. The safety of this product will also be evaluated.

An Open Label Study to Evaluate the Contraceptive Efficacy and Safety of Norethindrone Acetate Transdermal Delivery System.

Inclusion Criteria:

• Healthy females
• 18-45 years
• Regular, consistent menstrual cycles between 25 and 35 days
• Sexually active and at risk of becoming pregnant

Exclusion Criteria:

• History of infertility
• Known contraindications to progestogen administration
• Pap smear suggestive of a high-grade precancerous lesion(s)
• Clinically significant deviation from normal in any of the screening tests or exams