The study is the first large, controlled clinical trial to directly compare 20 mcg and 35 mcg pills. Researchers found that common side effects such as bloating, breast tenderness and nausea were approximately 50 percent more common in women using Ortho Tri-Cyclen as compared to Mircette and Alesse.
Side effects, particularly in the first few months of pill use, are a significant factor in oral contraceptive (OC) compliance and continuation. While cycle control (bleeding or spotting between periods) was similar in all pills studied after the end of six cycles, Mircette and Ortho Tri-Cyclen users exhibited better cycle control in the first two cycles among starters (first-time birth control pill users).
Self-reported acne decreased in 43 percent of the Mircette starters and 19 percent of the Alesse starters, while 22 percent of the Ortho Tri-Cyclen starters experienced an increase in acne. There was less change in women changing from another oral contraceptive to one of these three pills (switchers), although Mircette users again demonstrated the greatest decrease in acne (16 percent), while Alesse users experienced no change and Ortho Tri-Cyclen users experienced a 22 percent increase. However, no product-specific differences in decrease of acne achieved statistical significance.
The study also indicates that the new low dose pills provide equally good contraceptive protection as the older preparations with higher estrogen levels. No pregnancies occurred among Mircette users, one among Alesse users and three among Ortho Tri-Cyclen users.
Michael J. Rosenberg, M.D., M.P.H., President, Health Decisions Inc., and Professor, Departments of Epidemiology and Obstetrics-Gynecology, University of North Carolina, Chapel Hill, conducted the study among 463 patients, examining cycle control, side effects, efficacy and pill discontinuation.
Although OC prescriptions are usually written for 35 mcg dose products, this study demonstrated that 20 mcg pills provide comparable cycle control, with fewer side effects and equally good contraceptive protection. "There is a misperception about lower dose pills," said Dr. Rosenberg. "We now know that users of 20 mcg pills like Alesse and Mircette actually experience far fewer side effects than users of 35 mcg pills, while maintaining the same or better cycle control and pregnancy prevention."
"Poor cycle control and side effects like bloating, breast tenderness and nausea in the first few months of pill use are the most common reasons why women discontinue the pill," explained Dr. Rosenberg. "We found the highest continuation rate for the two new OCs with 20 mcg of estrogen."
He continued, "This study tells us that there is no reason to restrict the use of 20 mcg pills. In fact, greater use of 20 mcg pills can improve the clinical acceptance of OCs and result in better compliance, less discontinuation, and fewer unintended pregnancies."
The results were published in Contraception ("Efficacy, Cycle Control and Side Effects of Low-and Lower-Dose Oral Contraceptives: A Randomized Trial of 20 mcg and 35 mcg Estrogen Preparations," 60: 321-329). The study was funded by Organon Inc., makers of Mircette.
Health Decisions, Inc. is a full-service clinical development organization that works with the pharmaceutical industry as well as non-profit and governmental organizations. The company was founded in 1989 with the objective of reducing the time and expense required to bring promising drugs and medical devices to market through the use of the Internet and new processes and software that take advantage of the Internet and other emerging technologies.