**Exhibit 31.1**

 

# **Certifications**

 

I,Mark Sieczkarek, certify that:

 

1.I have reviewed this report on Form 10-Q of Conceptus, Inc., a Delawarecorporation;

 

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

 

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

 

4. The registrant’s other certifying officer and I are responsible forestablishing and maintaining disclosure controls and procedures (as defined inExchange Act Rules 13a-15(e) and 15d-15(e)) and internal control over financialreporting (as defined in Exchange Act Rules 13a-15(f) and 15d-15(f)) for theregistrant and have:

 

a)              designed such disclosure controls andprocedures, or caused such disclosure controls and procedures to be designedunder our supervision, to ensure that material information relating to theregistrant, including its consolidated subsidiaries, is made known to us byothers within those entities, particularly during the period in which thisreport is being prepared;

 

b)             designed such internal control over financialreporting, or caused such internal control over financial reporting to bedesigned under our supervision, to provide reasonable assurance regarding thereliability of financial reporting and the preparation of financial statementsfor external purposes in accordance with generally accepted accountingprinciples;

 

c)              evaluated the effectiveness of the registrant’sdisclosure controls and procedures and presented in this report our conclusionabout the effectiveness of the disclosure controls and procedures, as or theend of the period covered by this report based on such evaluation; and

 

d)             disclosed in this report any change in theregistrant’s internal control over financial reporting that occurred during theregistrant’s most recent fiscal quarter (the registrant’s fourth fiscal quarterin the case of an annual report) that has materially affected, or is reasonablylikely to materially affect, the registrant’s internal control over financialreporting; and

 

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

 

a)              all significant deficiencies and materialweaknesses in the design or operation of internal control over financialreporting which are reasonably likely to adversely affect the registrant’sability to record, process, summarize and report financial information; and

 

b)             any fraud, whether or not material, thatinvolves management or other employees who have a significant role in theregistrant’s internal control over financial reporting.

 

Date:  May 9, 2005

 
| /s/ Mark M. Sieczkarek                |   |
|---------------------------------------|--------|
| 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-Q of Conceptus, Inc., a Delawarecorporation;

 

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

 

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

 

4. The registrant’s other certifying officerand I are responsible for establishing and maintaining disclosure controls andprocedures (as defined in Exchange Act Rules 13a-15(e) and 15d-15(e)) andinternal control over financial reporting (as defined in Exchange Act Rules13a-15(f) and 15d-15(f)) for the registrant and have:

 

a)              designed such disclosure controls andprocedures, or caused such disclosure controls and procedures to be designedunder our supervision, to ensure that material information relating to theregistrant, including its consolidated subsidiaries, is made known to us byothers within those entities, particularly during the period in which thisreport is being prepared;

 

b)          designed such internal control over financialreporting, or caused such internal control over financial reporting to bedesigned under our supervision, to provide reasonable assurance regarding thereliability of financial reporting and the preparation of financial statementsfor external purposes in accordance with generally accepted accountingprinciples;

 

c)              evaluated the effectiveness of the registrant’sdisclosure controls and procedures and presented in this report our conclusionabout the effectiveness of the disclosure controls and procedures, as or theend of the period covered by this report based on such evaluation; and

 

d)             disclosed in this report any change in theregistrant’s internal control over financial reporting that occurred during theregistrant’s most recent fiscal quarter (the registrant’s fourth fiscal quarterin the case of an annual report) that has materially affected, or is reasonablylikely to materially affect, the registrant’s internal control over financialreporting; and

 

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

 

a)              all significant deficiencies and materialweaknesses in the design or operation of internal control over financialreporting which are reasonably likely to adversely affect the registrant’sability to record, process, summarize and report financial information; and

 

b)             any fraud, whether or not material, thatinvolves management or other employees who have a significant role in theregistrant’s internal control over financial reporting.

 

 

Date:  May 9, 2005

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

 

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