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                                                                   Exhibit 10.25


                         QUATRX PHARMACEUTICALS COMPANY
                        2006 EMPLOYEE STOCK PURCHASE PLAN

      1. ESTABLISHMENT OF PLAN.

      QuatRx Pharmaceuticals Company (the "COMPANY") proposes to grant options
for purchase of the Company's Common Stock (the "COMMON STOCK") to eligible
employees of the Company and its Participating Subsidiaries (as hereinafter
defined) pursuant to this 2006 Employee Stock Purchase Plan (this "PLAN"). For
the purposes of this Plan, "PARENT CORPORATION" and "SUBSIDIARY" shall have the
same meanings as "parent corporation" and "subsidiary corporation" in Sections
424(e) and 424(f), respectively, of the Internal Revenue Code of 1986, as
amended (the "CODE"). "PARTICIPATING SUBSIDIARIES" are Parent Corporations or
Subsidiaries that the Board of Directors of the Company (the "BOARD") designates
from time to time as corporations that shall participate in this Plan. The
Company intends this Plan to qualify as an "employee stock purchase plan" under
Section 423 of the Code (including any amendments to or replacements of such
Section), and this Plan shall be so construed. Any term not expressly defined in
this Plan but defined for purposes of Section 423 of the Code shall have the
same definition herein.

      2. NUMBER OF SHARES.


      The total number of shares of Common Stock initially reserved and
available for issuance pursuant to this Plan shall be 250,000, plus an annual
increase on the first day of each of the Company's fiscal years beginning on
January 1, 2007 equal to the lesser of (i) two percent (2%) of the shares of
Common Stock outstanding on the last day of the immediately preceding fiscal
year, (ii) 500,000 shares of Common Stock or (iii) such lesser number of shares
of Common Stock as the Board shall determine (the "Share Limit"), subject to
adjustments effected in accordance with Section 15 of this Plan. Shares issued
under this Plan may consist, in whole or in part, of authorized and unissued
shares or treasury shares reacquired in private transactions or open market
purchases, but all shares issued under this Plan shall be counted against the
Share Limit.


      3. PURPOSE.

      The purpose of this Plan is to provide eligible employees, including
officers of the Company and Participating Subsidiaries with a convenient means
of acquiring an equity interest in the Company through payroll deductions, to
enhance such employees' sense of participation in the affairs of the Company and
Participating Subsidiaries, and to provide an incentive for continued
employment. For the purposes of this Plan, "EMPLOYEE" shall mean any individual
who is an employee of the Company or a Participating Subsidiary. Whether an
individual qualifies as an employee shall be determined by the Committee, in its
sole discretion. The Committee shall be guided by the provisions of Treasury
Regulation Section 1.421-7 and Section 3401(c) of the Code and the Treasury
Regulations thereunder, with the intent that this Plan cover all "employees"
within the meaning of those provisions other than those who are not eligible to
participate in this Plan; provided, however, that any determinations regarding
whether an individual is an "employee" shall be prospective only, unless
otherwise determined by the

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Committee (as hereinafter defined). Unless the Committee makes a contrary
determination, the employees of the Company shall, for all purposes of this
Plan, be those individuals who are carried as employees of the Company or a
Participating Subsidiary for regular payroll purposes or are on a leave of
absence for not more than 90 days. Any inquiries regarding eligibility to
participate in this Plan shall be directed to the Committee, whose decision
shall be final.

      4. ADMINISTRATION.

      This Plan shall be administered by the Compensation Committee of the Board
(the "COMMITTEE"). Subject to the provisions of this Plan and the limitations of
Section 423 of the Code or any successor provision in the Code, all questions of
interpretation or application of this Plan shall be determined by the Committee
and its decisions shall be final and binding upon all participants. Members of
the Committee shall receive no compensation for their services in connection
with the administration of this Plan, other than standard fees as established
from time to time by the Board for services rendered by Board members serving on
Board committees. All expenses incurred in connection with the administration of
this Plan shall be paid by the Company.

      5. ELIGIBILITY.

      Any employee of the Company or the Participating Subsidiaries is eligible
to participate in an Offering Period (as hereinafter defined) under this Plan
except the following:

            (a) employees who are not employed by the Company or a Participating
Subsidiary prior to the beginning of such Offering Period or prior to such other
time period as specified by the Committee;

            (b) employees who are customarily employed for twenty (20) hours or
less per week;

            (c) employees who are customarily employed for five (5) months or
less in a calendar year;

            (d) employees who, together with any other person whose stock would
be attributed to such employee pursuant to Section 424(d) of the Code, own stock
or hold options to purchase stock possessing five percent (5%) or more of the
total combined voting power or value of all classes of stock of the Company or
any of its Participating Subsidiaries or who, as a result of being granted an
option under this Plan with respect to such Offering Period, would own stock or
hold options to purchase stock possessing five percent (5%) or more of the total
combined voting power or value of all classes of stock of the Company or any of
its Participating Subsidiaries;

            (e) individuals who provide services to the Company or any of its
Participating Subsidiaries as independent contractors who are reclassified as
common law employees for any reason except for federal income and employment tax
purposes; and

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            (f) employees who reside in countries for whom such employees'
participation in this Plan would result in a violation under any corporate or
securities laws of such country of residence.

      6. OFFERING DATES.

      The offering periods of this Plan (each, an "OFFERING PERIOD") shall be of
six (6) months duration commencing and ending on such dates as determined by the
Committee, provided that in no event shall an Offering Period commence prior to
the effective date of an initial public offering of the Company's securities.
The first business day of each Offering Period is referred to as the "OFFERING
DATE." The last business day of each Offering Period is referred to as the
"PURCHASE DATE." The Committee shall have the power to change the Offering
Dates, the Purchase Dates and the duration of Offering Periods; provided,
however, that no Offering Period shall have a duration of more than twenty-seven
(27) months.

      7. PARTICIPATION IN THIS PLAN.

      Eligible employees may become participants in an Offering Period under
this Plan on the Offering Date, after satisfying the eligibility requirements,
by delivering a subscription agreement to the Company prior to such Offering
Date, or such other time period as specified by the Committee. An eligible
employee who does not deliver a subscription agreement to the Company after
becoming eligible to participate in an Offering Period shall not participate in
that Offering Period or any subsequent Offering Period unless such employee
enrolls in this Plan by delivering a subscription agreement with the Company
prior to such Offering Period, or such other time period as specified by the
Committee. Once an employee becomes a participant in an Offering Period by
filing a subscription agreement, such employee shall automatically participate
in the Offering Period commencing immediately following the last day of the
prior Offering Period unless the employee withdraws or is deemed to withdraw
from this Plan or terminates further participation in the Offering Period as set
forth in Section 12 below. Such participant is not required to file any
additional subscription agreement in order to continue participation in this
Plan.

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      8. GRANT OF OPTION ON ENROLLMENT.

      Enrollment by an eligible employee in this Plan with respect to an
Offering Period shall constitute the grant (as of the Offering Date) by the
Company to such employee of an option to purchase on the Purchase Date up to
that number of shares of Common Stock determined by a fraction, the numerator of
which is the amount accumulated in such employee's payroll deduction account
during such Offering Period and the denominator of which is the lower of (i)
eighty-five percent (85%) of the fair market value of a share of the Company's
Common Stock on the Offering Date (but in no event less than the par value of a
share of the Company's Common Stock), or (ii) eighty-five percent (85%) of the
fair market value of a share of Common Stock on the Purchase Date (but in no
event less than the par value of a share of the Company's Common Stock);
provided, however, that the number of shares of Common Stock subject to any
option granted pursuant to this Plan shall not exceed the number of shares
permitted under Section 11 below. The fair market value of a share of the
Company's Common Stock shall be determined as provided in Section 9 below.
Notwithstanding the foregoing, in the event of a change in generally accepted
accounting principles which would adversely affect the accounting treatment
applicable to any current Offering Period and subject to any requirements of the
Code and further subject to Section 26 below, the Committee may make such
changes to the number of Shares purchased at the end of the Offering Period or
the purchase price paid as are allowable under generally accepted accounting
principles and as it deems necessary in the sole discretion of the Committee to
avoid or minimize adverse accounting consequences.

      9. PURCHASE PRICE.

      The purchase price per share at which a share of Common Stock shall be
sold in any Offering Period shall be eighty-five percent (85%) of the lesser of:

            (a) the fair market value on the Offering Date; or

            (b) the fair market value on the Purchase Date.

      For the purposes of this Plan, the term "FAIR MARKET VALUE" means, as of
any date, the value of a share of the Company's Common Stock determined as
follows:

            (a) if such Common Stock is then quoted on the Nasdaq National
Market, its closing price on the Nasdaq National Market on the date of
determination as reported in The Wall Street Journal or such other publication
source as the Committee determines to be reliable;

            (b) if such Common Stock is publicly traded and is then listed on a
national securities exchange, its closing price on the date of determination on
the principal national securities exchange on which the Common Stock is listed
or admitted to trading as reported in The Wall Street Journal or such other
publication source as the Committee determines to be reliable; or

            (c) if such Common Stock is publicly traded but is not quoted on the
Nasdaq National Market nor listed or admitted to trading on a national
securities exchange, the average of the closing bid and asked prices on the date
of determination as reported in The Wall Street


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Journal or such other publication source, including the Pink Sheets, as the
Committee determines to be reliable.

      10. PAYMENT OF PURCHASE PRICE; CHANGES IN PAYROLL DEDUCTIONS; ISSUANCE OF
SHARES.

            (a) The purchase price of the shares is accumulated by regular
payroll deductions made during each Offering Period. The deductions are made as
a percentage of the participant's compensation in one percent (1%) increments,
not less than one percent (1%), nor greater than ten percent (10%), or such
lower limit set by the Committee. Compensation shall mean all W-2 cash
compensation, including, but not limited to, base salary, wages, bonuses,
incentive compensation, commissions, overtime and shift premiums, plus draws
against commissions; provided, however that compensation shall not include any
long term disability or workers compensation payments, car allowances,
relocation payments, expense reimbursements or any compensation arising in
connection with any equity awards; and further provided, however, that for
purposes of determining a participant's compensation, any election by such
participant to reduce his or her regular cash remuneration under Sections 125 or
401(k) of the Code shall be treated as if the participant did not make such
election. Payroll deductions shall commence on the first payday of the Offering
Period and shall continue to the end of the Offering Period unless sooner
altered or terminated as provided in this Plan.


            (b) A participant may decrease the rate of payroll deductions once
during an Offering Period by filing with the Company a new authorization for
payroll deductions, in which case the new rate shall become effective for the
next payroll period commencing after the Company's receipt of the authorization
and shall continue for the remainder of the Offering Period unless changed as
described below. Such decrease in the rate of payroll deductions may be made at
any time during an Offering Period; provided, however, that a change to decrease
payroll deductions to zero shall be governed by Section 10(c) below. A
participant may not increase the rate of payroll deductions during an Offering
Period. A participant may increase or decrease the rate of payroll deductions
for any subsequent Offering Period by filing with the Company a new
authorization for payroll deductions prior to the beginning of such Offering
Period, or such other time period as specified by the Committee.


            (c) A participant may reduce his or her payroll deduction percentage
to zero during an Offering Period by filing with the Company a request for
cessation of payroll deductions. Such reduction shall be effective beginning
with the next payroll period after the Company's receipt of the request and no
further payroll deductions shall be made for the duration of the Offering
Period. Payroll deductions credited to the participant's account prior to the
effective date of the request shall be used to purchase shares of Common Stock
of the Company in accordance with Section 10(e) below. A participant may not
resume making payroll deductions during the Offering Period in which he or she
reduced his or her payroll deductions to zero.

            (d) All payroll deductions made for a participant are credited to
his or her account under this Plan and are deposited with the general funds of
the Company. No interest accrues on the payroll deductions. All payroll
deductions received or held by the Company may be used by


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the Company for any corporate purpose, and the Company shall not be obligated to
segregate such payroll deductions.

            (e) On each Purchase Date, for so long as this Plan remains in
effect and provided that the participant has not submitted before that date a
signed and completed withdrawal form, which notifies the Company that the
participant wishes to withdraw from that Offering Period under this Plan and
have all payroll deductions accumulated in the account maintained on behalf of
the participant, as of that date returned to the participant, the Company shall
apply the funds then in the participant's account to the purchase of whole
shares of Common Stock reserved under the option granted to such participant
with respect to the Offering Period to the extent that such option is
exercisable on the Purchase Date. The purchase price per share shall be as
specified in Section 9 of this Plan. Any cash remaining in a participant's
account after such purchase of shares shall be refunded to such participant in
cash, without interest; provided, however, that any amount remaining in such
participant's account on a Purchase Date which is less than the amount necessary
to purchase a full share of Common Stock shall be carried forward, without
interest, into the next Offering Period, as the case may be. In the event that
this Plan has been oversubscribed, all funds not used to purchase shares on the
Purchase Date shall be returned to the participant, without interest. No Common
Stock shall be purchased on a Purchase Date on behalf of any employee whose
participation in this Plan has terminated prior to such Purchase Date.

            (f) As soon as practicable after the Purchase Date, the Company
shall issue shares for the participant's benefit representing the shares
purchased upon exercise of his or her option.

            (g) During a participant's lifetime, his or her option to purchase
shares hereunder is exercisable only by him or her. The participant shall have
no interest or voting rights in shares covered by his or her option until such
option has been exercised.

      11. LIMITATIONS ON SHARES TO BE PURCHASED.

            (a) No participant shall be entitled to purchase stock under this
Plan at a rate which, when aggregated with his or her rights to purchase stock
under all other employee stock purchase plans of the Company or any Subsidiary
in which the employee participates, exceeds $25,000 in fair market value
(determined as of the Offering Date) for each calendar year in which any such
right to purchase stock granted to such participant is outstanding at any time.
The Company shall automatically suspend the payroll deductions of any
participant as necessary to enforce such limit provided that when the Company
automatically resumes such payroll deductions, the Company must apply the rate
in effect immediately prior to such suspension.

            (b) No participant shall be entitled to purchase more than the
Maximum Share Amount (as defined below) on any Purchase Date. Prior to the
commencement of any Offering Period or prior to such time period as specified by
the Committee, the Committee may, in its sole discretion, specify a maximum
number of shares which may be purchased by any employee at any single Purchase
Date (hereinafter the "MAXIMUM SHARE AMOUNT") or change the Maximum Share
Amount. The initial Maximum Share Amount under this Plan shall be 2,500 shares.
If a new Maximum Share Amount is set, then all participants must be notified of
such Maximum


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Share Amount prior to the commencement of the next Offering Period as to which
such new limit applies. The Maximum Share Amount shall continue to apply with
respect to all succeeding Offering Periods unless revised by the Committee as
set forth above.

            (c) If the number of shares to be purchased on a Purchase Date by
all employees participating in this Plan exceeds the number of shares then
available for issuance under this Plan, then the Company shall make a pro rata
allocation of the remaining shares in as uniform a manner as shall be reasonably
practicable and as the Committee shall determine to be equitable. In such event,
the Company shall give written notice of such reduction of the number of shares
to be purchased under a participant's option to each participant affected.

            (d) Any payroll deductions accumulated in a participant's account
which are not used to purchase stock due to the limitations in this Section 11
shall be returned to the participant as soon as practicable after the end of the
applicable Purchase Period, without interest.

      12. WITHDRAWAL.

            (a) Each participant may withdraw from an Offering Period under this
Plan by signing and delivering to the Company a written notice to that effect on
a form provided for such purpose. Such withdrawal may be elected at any time
prior to the end of an Offering Period, or such other time period as specified
by the Committee.

            (b) Upon withdrawal from this Plan, the accumulated payroll
deductions shall be returned to the withdrawn participant, without interest, and
his or her interest in this Plan shall terminate. In the event a participant
voluntarily elects to withdraw from this Plan, he or she may not resume his or
her participation in this Plan during the same Offering Period, but he or she
may participate in any Offering Period under this Plan which commences on a date
subsequent to such withdrawal by filing a new authorization for payroll
deductions in the same manner as set forth in Section 7 above for initial
participation in this Plan.

      13. TERMINATION OF EMPLOYMENT.

      Termination of a participant's employment for any reason, including
retirement, death, disability or the failure of a participant to remain an
eligible employee of the Company or of a Participating Subsidiary, shall
immediately terminate his or her participation in this Plan. In such event, the
payroll deductions credited to the participant's account shall be returned to
him or her or, in the case of his or her death, to his or her legal
representative, without interest. For purposes of this Section 13, an employee
shall not be deemed to have terminated employment or failed to remain in the
continuous employ of the Company or of a Participating Subsidiary in the case of
sick leave, military leave, or any other leave of absence approved by the Board,
provided, however that such leave is for a period of not more than ninety (90)
days or reemployment upon the expiration of such leave is guaranteed by contract
or statute.

      14. RETURN OF PAYROLL DEDUCTIONS.

      In the event a participant's interest in this Plan is terminated by
withdrawal, termination of employment or otherwise, or in the event this Plan is
terminated by the Board, the Company


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shall deliver to the participant all payroll deductions credited to such
participant's account. No interest shall accrue on the payroll deductions of a
participant in this Plan.

      15. CAPITAL CHANGES.

      Subject to any required action by the stockholders of the Company, the
number and type of shares of Common Stock covered by each option under this Plan
which has not yet been exercised and the number and type of shares of Common
Stock which have been authorized for issuance under this Plan but have not yet
been placed under option (collectively, the "RESERVES"), as well as the price
per share of Common Stock covered by each option under this Plan which has not
yet been exercised and the Maximum Share Amount, shall be proportionately
adjusted for any increase or decrease in the number of issued and outstanding
shares of Common Stock of the Company resulting from a stock split or the
payment of a stock dividend (but only on the Common Stock), any other increase
or decrease in the number of issued and outstanding shares of Common Stock
effected without receipt of any consideration by the Company or other change in
the corporate structure or capitalization affecting the Company's present Common
Stock; provided, however, that conversion of any convertible securities of the
Company shall not be deemed to have been "effected without receipt of
consideration." Such adjustment shall be made by the Committee, whose
determination shall be final, binding and conclusive. Except as expressly
provided herein, no issue by the Company of shares of stock of any class, or
securities convertible into shares of stock of any class, shall affect, and no
adjustment by reason thereof shall be made with respect to, the number or price
of shares of Common Stock subject to an option.

      In the event of the proposed dissolution or liquidation of the Company,
the Offering Period shall terminate immediately prior to the consummation of
such proposed action, unless otherwise provided by the Committee. The Committee
may, in the exercise of its sole discretion in such instances, declare that this
Plan shall terminate as of a date fixed by the Committee and give each
participant the right to purchase shares under this Plan as of a date on or
prior to such termination. In the event of (i) a sale, lease or other
disposition of all or substantially all of the assets of the Company, (ii) a
merger or consolidation in which the Company is not the surviving corporation,
(iii) a reverse merger in which the Company is the surviving corporation but the
shares of Common Stock outstanding immediately preceding the merger are
converted by virtue of the merger into other property, whether in the form of
securities, cash or otherwise, or (iv) the acquisition, sale or transfer of more
than 50% of the outstanding shares of the Company by tender offer or similar
transaction, this Plan shall continue with regard to Offering Periods that
commenced prior to the closing of the proposed transaction and shares shall be
purchased based on the Fair Market Value of the surviving corporation's stock on
an upcoming Purchase Date, unless otherwise provided by the Committee (including
by terminating the Plan in the manner specified in the preceding sentence).

      The Committee may, if it so determines in the exercise of its sole
discretion, also make provision for adjusting the Reserves, as well as the price
per share of Common Stock covered by each outstanding option, in the event that
the Company effects one or more reorganizations, recapitalizations, rights
offerings or other increases or reductions of shares of its outstanding Common
Stock, or in the event of the Company being consolidated with or merged into any
other corporation.

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      16. NONASSIGNABILITY.

      Neither payroll deductions credited to a participant's account nor any
rights with regard to the exercise of an option or to receive shares under this
Plan may be assigned, transferred, pledged or otherwise disposed of in any way
(other than by the laws of descent and distribution or as provided in Section 23
below) by the participant. Any such attempt at assignment, transfer, pledge or
other disposition shall be void and without effect.

      17. REPORTS.

      Individual accounts shall be maintained for each participant in this Plan.
Each participant shall receive, as soon as practicable after the end of each
Offering Period, a report of his or her account setting forth the total payroll
deductions accumulated, the number of shares purchased, the per share price
thereof and the remaining cash balance, if any, carried forward to the next
Offering Period.

      18. NOTICE OF DISPOSITION.

      Each participant shall notify the Company in writing if the participant
disposes of any of the shares purchased under the Plan, regardless of when such
disposition occurs. The Company may place a legend or legends on any certificate
representing shares acquired pursuant to this Plan requesting the Company's
transfer agent to notify the Company of any transfer of the shares. The
obligation of the participant to provide notice of share dispositions shall
continue notwithstanding the placement of any such legend on the certificates.

      19. NO RIGHTS TO CONTINUED EMPLOYMENT.

      Neither this Plan nor the grant of any option hereunder shall confer any
right on any employee to remain in the employ of the Company or any
Participating Subsidiary, or restrict the right of the Company or any
Participating Subsidiary to terminate such employee's employment.

      20. EQUAL RIGHTS AND PRIVILEGES.

      All eligible employees shall have equal rights and privileges with respect
to this Plan so that this Plan qualifies as an "employee stock purchase plan"
within the meaning of Section 423 or any successor provision of the Code and the
related regulations. Any provision of this Plan which is inconsistent with
Section 423 or any successor provision of the Code shall, without further act or
amendment by the Company, the Committee or the Board, be reformed to comply with
the requirements of Section 423. This Section 20 shall take precedence over all
other provisions in this Plan.

      21. NOTICES.

      All notices or other communications by a participant to the Company under
or in connection with this Plan shall be deemed to have been duly given when
received in the form specified by the Company at the location, or by the person,
designated by the Company for the receipt thereof.

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      22. TERM; STOCKHOLDER APPROVAL.

      After this Plan is adopted by the Board, this Plan shall become effective
on such date as determined by the Committee. This Plan shall be approved by the
stockholders of the Company, in any manner permitted by applicable corporate
law, within twelve (12) months before or after the date this Plan is adopted by
the Board. No purchase of shares pursuant to this Plan shall occur prior to such
stockholder approval. This Plan shall continue until the earlier to occur of (a)
termination of this Plan by the Board (which termination may be effected by the
Board at any time), (b) issuance of all of the shares of Common Stock reserved
for issuance under this Plan, or (c) twenty (20) years from the adoption of this
Plan by the Board.

      23. DESIGNATION OF BENEFICIARY.

            (a) A participant may file a written designation of a beneficiary
who is to receive any shares and cash, if any, from the participant's account
under this Plan in the event of such participant's death subsequent to the end
of an Purchase Period but prior to delivery to him of such shares and cash. In
addition, a participant may file a written designation of a beneficiary who is
to receive any cash from the participant's account under this Plan in the event
of such participant's death prior to a Purchase Date.

            (b) Such designation of beneficiary may be changed by the
participant at any time by written notice. In the event of the death of a
participant and in the absence of a beneficiary validly designated under this
Plan who is living at the time of such participant's death, the Company shall
deliver such shares or cash to the executor or administrator of the estate of
the participant, or if no such executor or administrator has been appointed (to
the knowledge of the Company), the Company, in its discretion, may deliver such
shares or cash to the spouse or to any one or more dependents or relatives of
the participant, or if no spouse, dependent or relative is known to the Company,
then to such other person as the Company may designate.

      24. CONDITIONS UPON ISSUANCE OF SHARES; LIMITATION ON SALE OF SHARES.

      Shares shall not be issued with respect to an option unless the exercise
of such option and the issuance and delivery of such shares pursuant thereto
shall comply with all applicable provisions of law, domestic or foreign,
including, without limitation, the Securities Act, the Securities Exchange Act
of 1934, as amended, the rules and regulations promulgated thereunder, and the
requirements of any stock exchange or automated quotation system upon which the
shares may then be listed (collectively, "APPLICABLE LAWS"), and shall be
further subject to the approval of counsel for the Company with respect to such
compliance. The Company shall have no liability for failure to issue shares of
Common Stock under this Plan unless the Company can do so in accordance with all
Applicable Laws.

      25. GOVERNING LAW.

      This Plan shall be governed by the substantive laws (excluding the
conflict of laws rules) of the State of Delaware.

      26. AMENDMENT OR TERMINATION OF PLAN.

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            (a) The Board or the Committee may amend, alter, suspend or
terminate this Plan at any time, but any such amendment shall be subject to
approval of the stockholders of the Company in the manner and to the extent
required by Applicable Laws. In addition, without limiting the foregoing, unless
approved by the stockholders of the Company, no such amendment shall be made
that would:

                  i. materially increase the maximum number of shares that may
            be issued under this Plan (other than an adjustment pursuant to
            Section 15); or

                  ii. change the designation or class of persons eligible to
            participate under this Plan.

            (b) No amendment, alternation, suspension or termination of this
Plan shall impair the rights of any options previously granted under this Plan,
unless mutually agreed otherwise between the participant, as applicable, and the
Company, which agreement must be in writing and signed by the participant, as
applicable, and the Company; provided however that notwithstanding the
foregoing, the Board or the Committee may terminate the Plan or terminate or
change an ongoing Offering Period if it determines, in its sole discretion that
such termination or change is in the best interests of the Company or its
stockholders, including if continuation of the Plan or the Offering Period would
cause the Company to incur accounting charges as a result of operation of the
Plan. Termination of this Plan shall not affect the Committee's ability to
exercise the powers granted to it hereunder with respect to any options granted
under this Plan prior to the date of such termination that remain outstanding
following such Plan termination.

            (c) Neither the adoption of this Plan by the Board nor the
submission of this Plan to the stockholders of the Company for approval shall be
construed as creating any limitations on the power of the Board to adopt such
other incentive arrangements as it may deem desirable. The value of Common Stock
purchased pursuant to this Plan will not be included as compensation, earnings,
salaries or other similar terms used when calculating a participant's benefits
under any employee benefit plan sponsored by the Company or any Subsidiary
except as such plan otherwise expressly provides.


                                      -11-
<PAGE>



                         QUATRX PHARMACEUTICALS COMPANY
                        2006 EMPLOYEE STOCK PURCHASE PLAN

                             SUBSCRIPTION AGREEMENT

                                                             New Election ______
                                                       Change of Election ______

      1. I, ________________________, hereby elect to participate in the QuatRx
Pharmaceuticals Company 2006 Employee Stock Purchase Plan (the "Plan") for the
Offering Period commencing ______________ ____, _______ and subscribe to
purchase shares of the Company's Common Stock in accordance with this
Subscription Agreement and the terms of the Plan.

      2. I elect to have contributions in the amount of ____% of my
compensation, as described in Section 10(a) of the Plan, applied to this
purchase. I understand that this amount must not be less than 1% and not more
than 10% of my compensation during the Offering Period. (Please note that no
fractional percentages are permitted).

      3. I hereby authorize payroll deductions from each paycheck during the
Offering Period at the rate stated in Item 2 of this Subscription Agreement. I
understand that all payroll deductions made by me shall be credited to my
account under the Plan and that I may not make any additional payments into such
account. I understand that all payments made by me shall be accumulated for the
purchase of shares of Common Stock at the applicable purchase price determined
in accordance with the Plan, and that no interest shall accrue on such amounts
at any time. I further understand that, except as otherwise set forth in the
Plan, shares will be purchased for me automatically on the Purchase Date of each
Offering Period unless I become ineligible to continue participating in the Plan
or I otherwise withdraw from the Plan by giving written notice to the Company
for such purpose.

      4. I understand that I may discontinue at any time prior to the Purchase
Date my participation in the Plan as provided in Section 10 of the Plan. I
understand that I may change the rate of deductions for future Offering Periods
by filing a new Subscription Agreement, and any such change will be effective as
of the beginning of the next Offering Period. In addition, I acknowledge that,
unless I withdraw from the Plan as provided in Section 12 of the Plan or
otherwise become ineligible to participate in the Plan, my election as set forth
above will continue to be effective for each successive Offering Period.

      5. I have received a copy of the Company's most recent description of the
Plan and a copy of the complete "QuatRx Pharmaceuticals Company 2006 Employee
Stock Purchase Plan." I understand that my participation in the Plan is in all
respects subject to the terms of the Plan, which governs the terms of this
Subscription Agreement.

      6. Shares purchased for me under the Plan should be issued in the name(s)
of (name of employee or employee and spouse only):

________________________________

________________________________

                                      -12-
<PAGE>


      7. I understand that this tax summary is only a summary and is subject to
change. I further understand that I should consult a tax advisor concerning the
tax implications of the purchase and sale of stock under the Plan.

      Early Disposition (Prior to Expiration of Holding Periods): I understand
that if I dispose of any shares received by me pursuant to the Plan within two
years after the Offering Date (the first day of the Offering Period during which
I purchased such shares) or within one year after the Purchase Date, I will be
treated for federal income tax purposes as having received ordinary compensation
income at the time of such disposition in an amount equal to the excess of the
fair market value of the shares on the Purchase Date over the price which I paid
for the shares, regardless of whether I disposed of the shares at a price less
than their fair market value at the Purchase Date. The remainder of the gain or
loss, if any, recognized on such disposition will be treated as capital gain or
loss.

      Disposition After Holding Periods: If I dispose of such shares at any time
after expiration of the two-year and one-year holding periods, I understand that
I will be treated for federal income tax purposes as having received
compensation income only to the extent of an amount equal to the lesser of (a)
the excess of the fair market value of the shares at the time of such
disposition over the purchase price which I paid for the shares under the
option, or (b) 15% of the fair market value of the shares on the Offering Date.
The remainder of the gain or loss, if any, recognized on such disposition will
be treated as capital gain or loss.

      I hereby agree to notify the Company in writing within 30 days after the
date of any disposition of shares acquired hereunder, and I will make adequate
provision for federal, state or other tax withholding obligations, if any, which
arise upon the disposition of the Common Stock. The Company shall be entitled,
to the extent required by applicable law, to withhold from my compensation any
amount necessary to comply with applicable tax withholding requirements with
respect to the purchase or sale of shares under the Plan.

      8. I hereby agree to be bound by the terms of the Plan. The effectiveness
of this Subscription Agreement is dependent upon my eligibility to participate
in the Plan.



NAME (print): __________________________      SPOUSE'S SIGNATURE (necessary if
                                              beneficiary is not spouse):

SIGNATURE: _____________________________

SOCIAL SECURITY #: _____________________      _________________________________
                                             (Signature)


DATE: __________________________________      _________________________________
                                             (Print Name)

                                      -13-
<PAGE>


                         QUATRX PHARMACEUTICALS COMPANY
                        2006 EMPLOYEE STOCK PURCHASE PLAN

                              NOTICE OF WITHDRAWAL

      I, __________________________, hereby elect to withdraw my participation
in the QuatRx Pharmaceuticals Company 2006 Employee Stock Purchase Plan (the
"Plan") for the Offering Period that began on _________ ___, _____. This
withdrawal covers all contributions credited to my account and is effective on
the date designated below.

      I understand that all contributions credited to my account will be paid to
me within ten (10) business days of receipt by the Company of this Notice of
Withdrawal and that my option for such Offering Period will automatically
terminate, and that no further contributions for the purchase of shares can be
made by me during such Offering Period.

      I further understand and agree that I shall be eligible to participate in
succeeding offering periods only by delivering to the Company a new Subscription
Agreement.

Dated:___________________



      __________________________
      Signature of Employee


      __________________________
      Social Security Number


                                      -14-
<PAGE>




                         QUATRX PHARMACEUTICALS COMPANY

                        2006 EMPLOYEE STOCK PURCHASE PLAN

                             BENEFICIARY DESIGNATION

      In the event of my death, I hereby designate the following as my
beneficiary to receive all payments and shares due to me under the QuatRx
Pharmaceuticals Company 2006 Employee Stock Purchase Plan. I understand that my
Beneficiary Designation will be effective upon acknowledgement of receipt by
QuatRx Pharmaceuticals Company.

BENEFICIARY:

NAME:  (Please print)



________________________________________    Relationship: __________________
(First)       (Middle)        (Last)


___________________________
 (Address)

___________________________



SIGNATURE: _____________________________    DATE: ____________________

Print Name: _____________________

SOCIAL SECURITY #:  __________________________________________


SPOUSE'S SIGNATURE (necessary if beneficiary is not Employee's spouse):

___________________________
(Signature)
___________________________
(Print name)

MAIL OR DELIVER THIS FORM TO:

QUATRX PHARMACEUTICALS COMPANY
777 EAST EISENHOWER PARKWAY, SUITE 100
ANN ARBOR, MICHIGAN 48108

ACKNOWLEDGEMENT OF RECEIPT BY QUATRX PHARMACEUTICALS COMPANY:


By: _____________________  Dated: _____________________

Title: ____________________