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                                                                    EXHIBIT 31.1

                                 CERTIFICATIONS

I, Mark Sieczkarek, certify that:

1. I have reviewed this report on Form 10-K/A of Conceptus, Inc., a Delaware
corporation;

2. Based on my knowledge, this annual report does not contain any untrue
statement of a material fact or omit to state a material fact necessary to make
the statements made, in light of the circumstances under which such statements
were made, not misleading with respect to the period covered by this report;

3. Based on my knowledge, the financial statements, and other financial
information included in this report, fairly present in all material respects,
the financial condition, results of operations and cash flows of the registrant
as of, and for, the periods presented in this report;

4. The registrant's other certifying officers and I are responsible for
establishing and maintaining disclosure controls and procedures (as defined in
Exchange Act Rules 13a-15(e) and 15d-15(e)) for the registrant and have:

         a)   designed such disclosure controls and procedures, or caused such
              disclosure controls and procedures to be designed under our
              supervision, to ensure that material information relating to the
              registrant, including its consolidated subsidiaries, is made known
              to us by others within those entities, particularly during the
              period in which this report is being prepared;

         b)   evaluated the effectiveness of the registrant's disclosure
              controls and procedures and presented in this report our
              conclusion about the effectiveness of the disclosure controls and
              procedures, as or the end of the period covered by this report
              based on such evaluation; and

         c)   disclosed in this report any change in the registrant's internal
              control over financial reporting that occurred during the
              registrant's most recent fiscal quarter (the registrant's fourth
              fiscal quarter in the case of an annual report) that has
              materially affected, or is reasonably likely to materially affect,
              the registrant's internal control over financial reporting; and

5. The registrant's other certifying officer and I have disclosed, based on our
most recent evaluation of internal control over financial reporting, to the
registrant's auditors and the audit committee of registrant's board of directors
(or persons performing the equivalent functions):

         a)   all significant deficiencies and material weaknesses in the design
              or operation of internal control over financial reporting which
              are reasonably likely to adversely affect the registrant's ability
              to record, process, summarize and report financial information;
              and

         b)   any fraud, whether or not material, that involves management or
              other employees who have a significant role in the registrant's
              internal control over financial reporting.

Date:  April 30, 2004

/s/ Mark M. Sieczkarek
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Mark M. Sieczkarek
President and Chief Executive Officer
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I, Gregory E. Lichtwardt, certify that:

1. I have reviewed this report on Form 10-K/A of Conceptus, Inc., a Delaware
corporation;

2. Based on my knowledge, this annual report does not contain any untrue
statement of a material fact or omit to state a material fact necessary to make
the statements made, in light of the circumstances under which such statements
were made, not misleading with respect to the period covered by this report;

3. Based on my knowledge, the financial statements, and other financial
information included in this report, fairly present in all material respects,
the financial condition, results of operations and cash flows of the registrant
as of, and for, the periods presented in this report;

4. The registrant's other certifying officers and I are responsible for
establishing and maintaining disclosure controls and procedures (as defined in
Exchange Act Rules 13a-15(e) and 15d-15(e)) for the registrant and have:

         a)   designed such disclosure controls and procedures, or caused such
              disclosure controls and procedures to be designed under our
              supervision, to ensure that material information relating to the
              registrant, including its consolidated subsidiaries, is made known
              to us by others within those entities, particularly during the
              period in which this report is being prepared;

         b)   evaluated the effectiveness of the registrant's disclosure
              controls and procedures and presented in this report our
              conclusion about the effectiveness of the disclosure controls and
              procedures, as or the end of the period covered by this report
              based on such evaluation; and

         c)   disclosed in this report any change in the registrant's internal
              control over financial reporting that occurred during the
              registrant's most recent fiscal quarter (the registrant's fourth
              fiscal quarter in the case of an annual report) that has
              materially affected, or is reasonably likely to materially affect,
              the registrant's internal control over financial reporting; and

5. The registrant's other certifying officer and I have disclosed, based on our
most recent evaluation of internal control over financial reporting, to the
registrant's auditors and the audit committee of registrant's board of directors
(or persons performing the equivalent functions):

         a)   all significant deficiencies and material weaknesses in the design
              or operation of internal control over financial reporting which
              are reasonably likely to adversely affect the registrant's ability
              to record, process, summarize and report financial information;
              and

         b)   any fraud, whether or not material, that involves management or
              other employees who have a significant role in the registrant's
              internal control over financial reporting.

Date:  April 30, 2004

/s/ Gregory E. Lichtwardt
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Gregory E. Lichtwardt
Executive Vice President, Treasurer and Chief Financial Officer