New Published Data Supports Theorized Mechanism of Action for Permanent Birth Control Device From Conceptus.

Business & Health Editors

SAN CARLOS, Calif.--(BUSINESS WIRE)--Dec. 4, 2001

Two Publications Released: Second Study Reports Interim Data Showing

High Level of Patient Satisfaction and No Reported Pregnancies

Conceptus, Inc. (NASDAQ NM: CPTS), developer of the non-incisional permanent birth control procedure Essure(TM), today announced that data published this month in a leading medical journal, Fertility and Sterility, supports the theorized mechanism of action of Essure, in a study done with women several weeks before a planned hysterectomy.

A second study released in the respected women's health journal, Australia and New Zealand Journal of Obstetrics and Gynaecology, provides evidence of strong acceptance of this method of permanent birth control among women in clinical trials. Essure is currently an investigational device in the United States, and studies are ongoing to support the product's safety and effectiveness for purposes of filing a Premarket Approval Application with the U.S. Food and Drug Administration.

"Data from our study demonstrates Essure's ability to cause a tissue response that histologically shows a high rate of occlusion of the Fallopian tube. This is consistent with the 100% functional occlusion noted by the hysterosalpingograms done before the hysterectomies." said Rafael Valle, MD, Professor of Obstetrics and Gynecology, Northwestern University Medical School, and lead author. "Essure holds promise to be a new method offering women a transcervical alternative to incisional methods of tubal sterilization."

Important Tissue Response to Essure Design Described

The Essure device is a dynamically expanding micro-insert that consists of a stainless steel inner coil, an outer coil made from Nitinol, and polyethelene terephthalate (PET) fibers. The inner coil attaches the device to a guidewire used for placement in the fallopian tubes. The outer coil anchors the micro-insert in the fallopian tube, and the PET fibers are a mesh between the two coils. During the Essure procedure, the device is inserted through the cervix into the fallopian tubes through a catheter that covers the guidewire, from which the device is then released.

In the first study, forty-three women who required hysterectomy volunteered to have the Essure procedure in the weeks prior to removal of their uterus, allowing the response of their body to the device to be studied. Results showed tubal occlusion noted by hysterosalpingography (HSG, an x-ray procedure) in 100 percent of fallopian tubes with satisfactorily placed devices. 30 percent of Fallopian tubes in the hysterectomy study were not accessible due to existing pathology, and device placement was successful in nearly 70 percent of the attempts. Importantly, failure to place the device was considered to be device-related in only one fallopian tube (1 percent), in these pathologic uteri.

Following hysterectomy, histology data was also collected and analyzed. The PET fibers in the device appeared to elicit a strong inflammatory tissue response that extends into the space between the inner and outer coils of the Essure micro-insert. Tissue response varied according to the time elapsed after placement. In 4 weeks of wearing, nearly a complete occlusive response was seen while inflammatory response and tissue growth was more extensive in the fallopian tubes of patients who had worn the device for 8 or more weeks. The study concluded that the tissue response is predictable, occlusive in nature, was localized to the device and should provide long-term anchoring of the device.

Essure is Highly Acceptable to Women in Clinical Trial

Data published in the current issue of the Australia and New Zealand Journal of Obstetrics and Gynaecology, concerned the first participants in one of two clinical studies underway. The procedure was rated very highly by this group of 111 women who had the Essure micro-inserts placed at the first investigational site to enroll patients. At three and six months after the procedure, ninety-nine percent of women with the Essure micro-insert rated their comfort with the micro-inserts as "very good" to "excellent." Of the 78 women who had reached 12 months or more of follow-up, 100 per cent provided a rating of "good" to "excellent." The average time to place the micro-inserts with the hysteroscope was 18 minutes.

85 per cent of women in the study had successful device placement in both tubes; these women then underwent HSG at three months to evaluate micro-insert placement and tubal occlusion. Bilateral occlusion was shown in 98 percent of the women with satisfactorily placed devices. At six months, occlusion was achieved in 100 percent of these women. The device was used as the sole method of contraception by 108 women for 1894 women-months (mean reliance time 17 months, median 17 months). There were no reported intrauterine or ectopic pregnancies in this study of the current Essure procedure and device. 5 per cent of women experienced an adverse event that resulted in their inability to rely on the device for contraception.

"Data from this single clinical investigative site are illustrative of the positive response we have seen from women in all of the Essure clinical trials," said John Kerin, Professor, Department of Obstetrics and Gynecology, University of Adelaide. "The overwhelming majority of women consistently rate this method very highly."

Permanent Birth Control

Surgical tubal ligation has become the most common form of birth control

worldwide, despite the fact that it is invasive and costly. About 93 percent of the procedures in the U.S. are performed in a hospital or surgi-center under general anesthesia, requiring between four and five hours of hospital recovery time and three to10 days before returning to regular activities. An Essure procedure does not require cutting or penetrating the abdomen and can be performed in a less costly procedure setting without general anesthesia. Accordingly, a woman is expected to spend about two to three hours of her day for an Essure procedure and have a rapid return to regular activities. Essure does not involve taking drugs or hormones.

About Conceptus

Conceptus, Inc. is developing Essure, an innovative medical procedure, designed to provide a non-incisional alternative to tubal ligation, the leading form of birth control worldwide. Essure is currently an investigational device in the United States, and studies are ongoing to support the product's safety and effectiveness for purposes of filing a Premarket Approval Application with the U.S. Food and Drug Administration.

Data from the United Nations show that worldwide, 33 percent of reproductive couples using birth control rely on surgical tubal ligation. Additionally, a survey performed by the United States Centers for Disease Control and Prevention indicates that surgical tubal ligation continues to be the most prevalent form of birth control in the U.S., and that 35 percent of women age 35-44 have had a surgical tubal sterilization. An estimated 700,000 surgical tubal ligations are performed each year in the United States.

The Essure procedure is based on a unique and proprietary catheter delivery system for minimally invasive transcervical tubal access. Additional information about Conceptus and the Essure procedure 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 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, 2000 and other filings with the Securities and Exchange Commission.