Conceptus Achieves Milestone With Stop--tm-- Phase II Data.

Business & Health Editors

SAN CARLOS, Calif.--(BW HealthWire)--May 22, 2000

Conceptus, Inc. (NASDAQ NM: CPTS) announced the achievement of an important corporate milestone in the development of the STOP non-surgical permanent contraception device. Steve Bacich, President and CEO, stated, "Statistical analysis of interim Phase II study results allows us to quantify a confidence level in moving forward with the pivotal trial and plans to commercialize STOP internationally within a year."

Conceptus' consulting biostatistician, Daniel Cher, M.D. stated, "Women in the Phase II study have accumulated over 750 woman-months of effectiveness without a reported pregnancy. Based on statistical analysis of the interim Phase II study results to date, the projected one-year effectiveness rate of the STOP device in this trial has already reached 95%. Further, with each passing month without a pregnancy, this statistically projected rate becomes even more compelling and provides further confidence that the effectiveness criteria approved as part of the IDE submission for the pivotal trial will be met or exceeded.

Mr. Bacich added, "We are hopeful that our pivotal trial will demonstrate that the first year effectiveness rate of the STOP device exceeds the typical use rate of the pill (95%) and matches the 99% rate of surgical tubal ligation."

Mr. Bacich noted that these results include both the current and an earlier design of the STOP device and also clarified that as is true of all methods of birth control, STOP cannot be expected to be 100% effective. It should also be noted that the data gathered in the pivotal trial will be required to support a final effectiveness rate for pre-market approval (PMA) submission.

The Company made today's announcement at an investment community lunch presentation in San Francisco featuring guest speakers John F. Kerin, M.D., and Jay M. Cooper, M.D. Dr. Kerin, a leading clinical expert on STOP, is Professor, Reproductive Medicine Unit, University of Adelaide, Australia and Dr. Cooper is founder and medical director of Women's Health Research in Phoenix, Arizona and the U.S. principal investigator for the STOP pivotal study.

A recording of today's investment community meeting will be available on the Company's Web site, www.conceptus.com.

About STOP

Surgical tubal ligation has become the most common form of contraception worldwide, despite the fact that it is invasive and costly. About 93% of the procedures in the U.S. are performed in a hospital or surgi-center under general anesthesia, requiring 4-5 hours of hospital recovery time and resulting in 3-4 days off work. In contrast, because a STOP procedure does not require cutting or penetrating the abdomen, the procedure is performed with local sedation, thus enabling the procedure to be performed in a less costly office setting with reduced reliance on back-up emergency facilities and personnel. Accordingly, a woman is expected to spend about 2-3 hours of her day for a STOP procedure and have a rapid return to normal activities.

The STOP device is a unique and proprietary micro-coil that is deployed permanently into each fallopian tube using the Company's minimally invasive transcervical tubal access catheter system. Once in place, clinical studies have shown that the STOP device induces an occlusive tissue response.

About Conceptus

Conceptus, Inc. is developing STOP, an innovative medical device and procedure designed to provide a non-surgical alternative to tubal ligation, the leading form of contraception worldwide. Data from the United Nations show that worldwide, 30% of reproductive couples using contraception rely on surgical tubal ligation. Additionally, a survey performed by the Centers for Disease Control and Prevention indicates that surgical tubal ligation continues to be the most prevalent form of contraception in the U.S., and that 35% of women age 35-44 have had a surgical tubal sterilization. An estimated 800,000 surgical tubal ligations are performed each year in the U.S., of which 93% are performed in a hospital or surgi-center and require general anesthesia. Additional information about the Company and the STOP device is available at www.conceptus.com.

Except for the historical information contained herein, the matters discussed in this press release are forward-looking statements, the accuracy of which is necessarily subject to risks and uncertainties. The receipt of regulatory approvals, results of product development programs, and clinical efficacy of and market demand for products, among other matters discussed in this release, may differ significantly from the discussion of such matters in the forward-looking statements. Such differences may be based upon factors within the Company's control, such as strategic planning decisions by management and re-allocation of internal resources, or on factors outside of the Company's control, such as delays by regulatory authorities, scientific advances by Conceptus or third parties and introduction of competitive products, as well as those factors set forth in the Company's Annual Report on Form 10-K for the year ended December 31, 1999 and other filings with the Securities and Exchange Commission.