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                                                                 EXHIBIT 10.9(f)

                            SIXTH AMENDMENT TO LEASE

THIS SIXTH AMENDMENT TO LEASE (hereinafter "Amendment") is made this fifth day
of January 2001, by and between McCANDLESS LIMITED, a California limited
partnership (Landlord") and NOVACEPT, a California corporation formerly known as
Envision Surgical Systems, Inc. ("Tenant").

                                    RECITALS

         A. Tenant currently leases from Landlord approximately eleven thousand
four hundred and sixty-one (11,461) square feet of space (the "Premises") of
which approximately eight thousand six hundred and fifty (8,650) square feet of
space is located at 1047 Elwell Court, Palo Alto, California (the "1047 Elwell
Space") and approximately two thousand eight hundred and eleven (2,811) square
feet of additional space is located at 1056 Elwell Court, Palo Alto (the "1056
Elwell Space") pursuant to that certain lease dated August 26, 1993 as amended
by the First Amendment To Lease dated July 8, 1996, the Second Amendment To
Lease dated May 13, 1998, the Third Amendment To Lease dated July 13, 1999, the
Fourth Amendment To Lease dated August 4, 2000 and the Fifth Amendment To Lease
dated September 30, 2000 ("Lease").

         B. The term of the Lease expires on December 31, 2000 and Tenant
desires to extend the term of the Lease respecting the 1047 Elwell Space for
three (3) additional years and to extend the term respecting the 1056 Elwell
Space for six (6) additional months.

         C. Landlord is willing to so extend the term of the Lease on the terms
and conditions set forth herein.

NOW, THEREFORE, in consideration of the above recitals and the mutual covenants
and agreements contained herein and other good and valuable consideration the
receipt and sufficiency of which are hereby acknowledged, the parties hereby
agree as follows:

         1. Term. The term of the Lease respecting the 1047 Elwell Space is
hereby extended for three additional years, so that the term of the Lease shall
extend from January 1, 2001 to, and shall include, December 31, 2003. The term
of the Lease respecting the 1056 Elwell Space is hereby extended for six (6)
additional months, on a month to month basis from January 1, 2001 to, and
including, June 30, 2001 or sooner. The period commencing on January 1, 2001 and
ending on December 31, 2003 is referred to herein as the Sixth Extended Term.

         2. Square Footage. Upon the June 30, 2001 expiration of the term
respecting the 1056 Elwell Space, Tenant shall vacate the 1056 Elwell Space and
the square footage of the Premises shall be reduced from approximately eleven
thousand four hundred and sixty-one (11,461) square feet to approximately eight
thousand six hundred and fifty (8,650) square feet

         3. Basic Rent. The monthly basic rent as described in Paragraphs 4 (a)
and 5 of the Lease shall continue to be sixty three thousand and thirty-five and
50/100 dollars ($63,035.50) per month. The calculation for such basic rent is
reached by multiplying 11,461 square feet by $5.50 per square foot. Upon the
June 30, 2001 or sooner expiration of the term respecting, and Tenant's
relinquishment and surrender of, the 1056 Elwell Space, the monthly basic rent
shall be reduced to forty-seven thousand five hundred and seventy-five and
00/100 dollars ($47,575.00) per month, (8,650 square feet x $5.50 per square
foot).

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         4. Adjustments to Basic Rent. The monthly basic rent shall be increased
annually by five percent (5%) and otherwise adjusted as follows

<TABLE>
<S>                                                    <C>
January 1, 2001 through June 30, 2001 or sooner        $63,035.50 per month

July 1, 2001 or sooner through December 31, 2001       $47,575.00 per month

January 1, 2002 through December 31, 2002              $49,953.75 per month

January 1, 2003  through December 31, 2003             $52,451.44 per month
</TABLE>

         5. Basic Rent Credit. Notwithstanding the above, Tenant shall be
granted a ten thousand dollar ($10,000.00) credit applicable towards basic rent
to offset the cost of new carpeting, interior painting and other interior
improvements desired by Tenant. Such credit shall be applicable in the first
month following the completion of such interior improvement work exceeding
$10,000 in cost in the aggregate.

         6. Common Area Charges. Tenant shall continue to pay its proportionate
share of common area charges as set forth in paragraphs 5 (b) and 16 of the
Lease and paragraph 5 of the Second Amendment To Lease. Upon the June 30, 2001
expiration of the term respecting, and Tenant's surrender of, the 1056 Elwell
Space, Tenant shall pay no common area charges for the 1056 Elwell Space and
Tenant's proportionate share of common area charges for the 1047 Elwell Space
shall be 55.52% of the common area charges allocable to the building in which
the 1047 Elwell Space is located as described in paragraphs 5 (b) and 16 of the
Lease.

         7. Brokers. Each party represents that it has not had any dealings with
any real estate broker, finder or other person with respect to this Amendment,
and that there are no leasing commissions to be paid by Landlord or Tenant in
connection with this transaction. Each party hereto shall hold harmless the
other party from all damages, loss or liability resulting from any claims that
may be asserted against the other party by any broker, finder or other person
with whom such party has dealt, or purportedly has dealt, in connection with
this transaction.

         8. Restatement of Other Lease Terms. Except as specifically modified
herein, all other terms, covenants and conditions of the Lease, including
Tenant's obligation to pay common area charges, shall remain in full force and
effect.

IN WITNESS WHEREOF, the parties hereto have executed this Agreement as of the
day and year first above written.

LANDLORD:                                   TENANT:

McCANDLESS LIMITED,                         NOVACEPT, a California corporation
a California limited partnership            formerly known as Envision Surgical
                                            Systems, Inc.

By: /s/ Sandra M. Simons                     By: /s/ D.R. Nathe
-------------------------------------       ------------------------------------
Sandra Simons, as Trustee under the                     (Signature)
March 17,1998 Restatement of the
Charles S. McCandless and Jean A.           D.R. Nathe
McCandless Inter Vivos Trust Agreement      ------------------------------------
dated January 25, 1977, as amended by                 (Printed Name)
amendments dated April 14, 1998 and
July 27, 1999, a General Partner            VP Operations
                                            ------------------------------------
                                                         (Title)

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                                   EXHIBIT A

                                  [FLOOR PLAN]