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                                                                     EXHIBIT 3.1





                          FOURTH AMENDED AND RESTATED


                          CERTIFICATE OF INCORPORATION


                                       OF




                                 BIOFIELD CORP.



                                     under



                      The Delaware General Corporation Law
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                          FOURTH AMENDED AND RESTATED

                          CERTIFICATE OF INCORPORATION

                                       OF

                                 BIOFIELD CORP.




         Biofield Corp., a corporation organized and existing under the laws of
the State of Delaware (the "Corporation"), hereby certifies as follows:

         1.      The name of the Corporation is Biofield Corp.  The date of
filing of its original Certificate of Incorporation with the Secretary of State
was December 15, 1992.

         2.      On May 7, 1993, the Corporation filed an Amended and Restated
Certificate of Incorporation.

         3.      On November 3, 1993, the Corporation filed a Second Amended
 and Restated Certificate of Incorporation.

         4.      On March 1, 1994, the Corporation filed a Third Amended and
 Restated Certificate of Incorporation.

         5.      This Fourth Amended and Restated Certificate of Incorporation
restates, integrates and further amends the provisions of the Certificate of
Incorporation of this Corporation.  This Fourth Amended and Restated
Certificate of Incorporation was duly adopted by unanimous written consent of
the directors of the Corporation in accordance with Section 141(f) of the
General Corporation Law of the State of Delaware (the "DGCL") and majority
written consent of the





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stockholders of this Corporation in accordance with Section 228 of the DGCL.
In accordance with Section 228 of the DGCL, notice of such majority written
consent has been given to all stockholders who did not consent to the actions
taken thereby.

         6.      The text of the Certificate of Incorporation as heretofore
amended is hereby restated and further amended to read in its entirety as
follows:

         FIRST.  The name of the Corporation is BIOFIELD CORP.

         SECOND. The address, including street, number, city and county of the
Corporation's registered office in the State of Delaware is 32 Loockerman
Square, Suite L-100, City of Dover, County of Kent.  The name of its registered
agent at such address is The Prentice-Hall Corporation System, Inc.

         THIRD.  The purpose of the Corporation is to engage in any lawful act
or activity for which corporations may be organized under the General
Corporation Law of the State of Delaware.

         FOURTH. The aggregate number of shares which the Corporation shall
have the authority to issue is thirty-seven million (37,000,000) shares, par
value of $.001 per share, consisting of twenty-five million (25,000,000) shares
of Common Stock, par value $.001 per share; and twelve million (12,000,000)
shares of Preferred Stock, par value $.001 per share.  Such Preferred Stock
shall consist of two million three hundred fifty thousand (2,350,000) shares of
Series A Convertible Preferred Stock, par value $.001 per share (the "Series A
Preferred Stock"); five hundred thousand (500,000) shares of Series B





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Convertible Preferred Stock, par value $.001 per share (the "Series B Preferred
Stock"); four million one hundred thousand (4,100,000) shares of Series C
Convertible Preferred Stock, par value $.001 per share (the "Series C Preferred
Stock"); two million seven hundred fifty thousand (2,750,000) shares of Series
D Convertible Preferred Stock, par value $.001 per share (the "Series D
Preferred Stock"); and two million three hundred thousand (2,300,000) shares of
such Preferred Stock, par value $.001 per share, as may be established by the
Board of Directors pursuant to Article FIFTH hereof, subject to the protective
provisions of Paragraph 5 of Article FOURTH hereof.  (The Series A Preferred
Stock, the Series B Preferred Stock, the Series C Preferred Stock and the
Series D Preferred Stock are hereinafter collectively referred to as the
"Series Preferred Stock.")

         1.      Dividend Provisions.

                 The holders of shares of the Common Stock and the holders of
shares of Series Preferred Stock shall be entitled to dividends when and as
declared by the Board of Directors; provided, however, that holders of Series
Preferred Stock shall be entitled to receive dividends equivalent on a per
share basis to any dividends received by the holders of Common Stock or any
series of Preferred Stock ranking pari passu or junior to the Series Preferred
Stock, based upon the number of full shares of Common Stock into which such
shares of Series Preferred Stock could be converted pursuant to the provisions
of Paragraph 3 hereof, at the record date for the determination of shareholders
entitled to such





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dividends.  The Series A Preferred Stock, the Series B Preferred Stock, the
Series C Preferred Stock and the Series D Preferred Stock shall rank pari passu
with each other in respect of dividends.

         2.      Liquidation Preference.

                 (a)      Series Preferred Stock.

                          (i)     In the event of any liquidation, dissolution
or winding up of the Corporation, either voluntary or involuntary
(collectively, a "Liquidation"), each of the holders of the Series Preferred
Stock shall be entitled to receive prior and in preference to any distribution
of any of the assets of the Corporation to holders of Common Stock or Preferred
Stock ranking junior to the Series Preferred Stock, an amount per share as
follows: holders of Series Preferred Stock shall be entitled to receive an
amount of cash and/or property (which may include securities) equal to the sum
of the Series Liquidation Value (as defined below) for each outstanding share
of Series Preferred Stock, and all declared but unpaid dividends per share, and
no more.  If upon any such Liquidation, the remaining assets of the Corporation
available for distribution to its shareholders shall be insufficient to pay the
holders of shares of Series Preferred Stock the full amount to which they shall
be entitled, the holders of shares of Series Preferred Stock and any class or
series of stock ranking on liquidation on a parity with the Series Preferred
Stock shall share ratably in any distribution of the remaining assets and funds
of the Corporation in proportion to the respective amounts which would
otherwise





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be payable in respect of the shares held by them upon such distribution if all
amounts payable on or with respect to such shares were paid in full.  The
holders of the Series Preferred Stock shall each be given at least ten (10)
business days prior written notice of any such Liquidation during which period
such holders may exercise the conversion rights under Paragraph 3 hereof.  If
such notice is not given or is not feasible, the holders of the Series
Preferred Stock shall be entitled to receive the amount that such holders would
have received had their shares been converted immediately prior to Liquidation
if such amount is greater than the amount payable under the first sentence of
this subsection.  The holders of Series A Preferred Stock, Series B Preferred
Stock, Series C Preferred Stock and Series D Preferred Stock shall rank on
liquidation on a parity with each other.

                          (ii)    For purposes of this Fourth Amended and
Restated Certificate of Incorporation, the term "Series Liquidation Value"
means (a) Four Dollars and Fifty Cents ($4.50), in the case of Series A
Preferred Stock, Series B Preferred Stock and Series C Preferred Stock and (b)
Six Dollars ($6.00), in the case of Series D Preferred Stock.

                 (b)      Common Stock.  In the event of any Liquidation of the
Corporation, if there are any assets remaining available for distribution after
the distribution provided for above to the holders of Series Preferred Stock,
the holders of Common Stock shall be entitled to receive pro rata the entire
remaining assets of the Corporation legally available for distribution.





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                 (c)      Consolidation, Merger or Sale of the Corporation.  A
consolidation or merger of the Corporation with or into any other corporation
or corporations (other than a consolidation or merger in which the Corporation
is the continuing corporation), or a sale, conveyance or disposition of all or
substantially all of the assets of the Corporation or the effectuation by the
Corporation of a transaction or series of related transactions in which more
than fifty (50%) percent of the voting power of the Corporation is disposed of
(collectively, a "Sale of the Corporation"), shall be deemed to be a
Liquidation within the meaning of this Paragraph 2.

         3.      Conversion.

                 (a)      No holder of Common Stock shall have the right to
convert such shares into any other class of stock of the Corporation.

                 (b)      Each of the holders of the Series Preferred Stock
shall have conversion rights as follows (the "Conversion Rights"):

                          (i)     Right to Convert.  Each share of the Series
Preferred Stock shall be convertible, at the option of the holder thereof, at
any time after the date of issuance of such share, at the office of the
Corporation or any transfer agent for the Series Preferred Stock, into such
number of fully paid and non-assessable shares of Common Stock as is determined
by dividing the Series Liquidation Value plus all declared but unpaid dividends
per share on the date of conversion, by the conversion price at the time in
effect for such shares.  The initial conversion price for the Series A
Preferred Stock (the





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"Series A Conversion Price") shall be Four Dollars and Fifty Cents ($4.50) per
share, the initial conversion price for the Series B Preferred Stock (the
"Series B Conversion Price") shall be Four Dollars and Fifty Cents ($4.50) per
share, the initial conversion price for the Series C Preferred Stock (the
"Series C Conversion Price") shall be Four Dollars and Fifty Cents ($4.50) per
share and the initial conversion price for the Series D Preferred Stock (the
"Series D Conversion Price") shall be Six Dollars ($6.00) per share, provided,
however, that the Series A Conversion Price, the Series B Conversion Price, the
Series C Conversion Price and the Series D Conversion Price shall be subject to
adjustment as set forth in this Paragraph 3(b).

                          (ii)    Mechanics of Conversion.  Before any holder
of Series Preferred Stock shall be entitled to convert the same into shares of
Common Stock, he shall surrender the certificate or certificates therefor, duly
endorsed, at the office of the Corporation or of any transfer agent for such
Series Preferred Stock, and shall give written notice by mail, postage prepaid,
to the Corporation at its principal corporate office, of the election to
convert the same and shall state therein the name or names in which the
certificate or certificates for shares of Common Stock are to be issued.  The
Corporation shall, as soon as practicable thereafter, issue and deliver at such
office to such holder of the Series Preferred Stock, or to the nominee or
nominees of such holder, a certificate or certificates for the number of shares
of Common Stock to which such holder shall be entitled as aforesaid.  Such
conversion shall be





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deemed to have been made immediately prior to the close of business on the date
of such surrender of the shares of the Series Preferred Stock to be converted,
and the person or persons entitled to receive the shares of Common Stock
issuable upon such conversion shall be treated for all purposes as the record
holder or holders of such shares of Common Stock as of such date.

                          (iii)   Conversion Price Adjustments of Series
Preferred Stock. As used in this Subsection, "Employee Shares" shall mean up to
3,000,000 shares of Common Stock issued or issuable to employees, officers,
directors and consultants of the Corporation pursuant to stock purchase or
stock option plans or arrangements, or both, approved by the Board of
Directors; "Warrant Shares" shall mean (i) shares of Common Stock issuable upon
exercise of (A) those warrants (including up to 155,556 shares of Common Stock
issuable upon exercise of such warrants) issued or issuable to Musket Research
Associates, Inc., or other selected dealers, in connection with the sale of the
Series C Securities (as defined below), (B) those warrants (including up to
211,989 shares of Common Stock issuable upon exercise of such warrants) issued
to Oppenheimer & Co., Inc. in connection with a private placement of the Series
A Preferred Stock, (C) those warrants (including up to 5,800 shares of Common
Stock issuable upon exercise of such warrants) issued to Craig & Associates,
Inc. in connection with a private placement of the Series B Preferred Stock,
(D) those warrants (including up to 46,625 shares of Common Stock issuable upon
exercise of such warrants) issued to various selected dealers in connection
with a private





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placement of Common Stock, and (ii) shares of Preferred Stock and Common Stock
issuable upon exercise of those warrants (the "Warrants") issued or issuable to
GS Capital Partners, L.P. ("GSCP") and certain other investors in connection
with a private placement of the Series C Securities (as defined below) (the
Warrants to purchase Preferred Stock are referred to as the "Preferred Stock
Warrants"); "Series C Securities" shall mean the securities issued or issuable
to GSCP and certain other investors at a price of $4.50 per unit, with each
such unit consisting of (i) one share of Series C Preferred Stock, (ii)
one-half of a warrant (a "$6.00 Warrant") to purchase a share of Series D
Preferred Stock at an initial exercise price of $6.00 per warrant, (iii)
one-half of a warrant (an "Adjustable Warrant") to purchase one share of Series
D Preferred Stock at an initial exercise price of $6.00 per warrant or, upon
the occurrence of certain events, one share of Series C Preferred Stock at an
initial exercise price of $4.50 per warrant, and (iv) the right, upon the
occurrence of certain events to receive, for no additional consideration,
one-quarter of a warrant (an "Additional Warrant") to purchase one share of
Common Stock at an initial exercise price of $4.50 per warrant.  The number of
Employee Shares and Warrant Shares shall, generally, be subject to appropriate
adjustment for stock splits, stock dividends, combinations and other similar
recapitalizations affecting such shares.  Except in the case of the issuance of
the Series C Securities, Employee Shares, Warrant Shares and shares issued upon
conversion of Series Preferred Stock (in which event the provisions of this
Paragraph 3(b) shall not apply),





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the Series A Conversion Price, the Series B Conversion Price, the Series C
Conversion Price and the Series D Conversion Price shall be subject to
adjustment from time to time as follows:

                                  (1)      In the event the Corporation should
at any time or from time to time after the date of filing of this Amended and
Restated Certificate of Incorporation (the "Filing Date") fix a record date for
(x) the effectuation of a subdivision (by any stock split or otherwise) of the
outstanding shares of Common Stock or (y) the determination of holders of
Common Stock entitled to receive a dividend or other distribution payable in
additional shares of Common Stock or other securities or rights convertible
into or exercisable for, or entitling the holder thereof to receive directly or
indirectly, additional shares of Common Stock (hereinafter referred to as
"Common Stock Equivalents") without payment of any consideration by such holder
for the additional shares of Common Stock or the Common Stock Equivalents,
including the additional shares of Common Stock issuable upon conversion or
exercise thereof, then, as of such record date (or the date of such dividend,
distribution, split, subdivision or determination if no record date is fixed),
(i) the Series A Conversion Price shall be appropriately decreased to an amount
equal to the Series A Conversion Price in effect on the record date (or the
date of such dividend, distribution, split, subdivision or determination if no
record date is fixed) times a fraction, the numerator of which shall be the
number of shares of Common Stock outstanding before the dividend, subdivision,





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distribution or split and the denominator of which shall be the number of
shares of Common Stock outstanding after the dividend, subdivision,
distribution or split (assuming the exercise or conversion of all Common Stock
Equivalents issued or issuable pursuant to such dividend, subdivision,
distribution or split), (ii) the Series B Conversion Price shall be
appropriately decreased to an amount equal to the Series B Conversion Price in
effect on the record date (or the date of such dividend, distribution, split,
subdivision or determination if no record date is fixed) times a fraction, the
numerator of which shall be the number of shares of Common Stock outstanding
before the dividend, subdivision, distribution or split and the denominator of
which shall be the number of shares of Common Stock outstanding after the
dividend, subdivision, distribution or split (assuming the exercise or
conversion of all Common Stock Equivalents issued or issuable pursuant to such
dividend, subdivision, distribution or split), (iii) the Series C Conversion
Price shall be appropriately decreased to an amount equal to the Series C
Conversion Price in effect on the record date (or the date of such dividend,
distribution, split, subdivision or determination if no record date is fixed)
times a fraction, the numerator of which shall be the number of shares of
Common Stock outstanding before the dividend, subdivision, distribution or
split and the denominator of which shall be the number of shares of Common
Stock outstanding after the dividend, subdivision, distribution or split
(assuming the exercise or conversion of all Common Stock Equivalents issued or
issuable pursuant to such





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dividend, subdivision, distribution or split) and (iv) the Series D Conversion
Price shall be appropriately decreased to an amount equal to the Series D
Conversion Price in effect on the record date (or the date of such dividend,
distribution, split, subdivision or determination if no record date is fixed)
times a fraction, the numerator of which shall be the number of shares of
Common Stock outstanding before the dividend, subdivision, distribution or
split and the denominator of which shall be the number of shares of Common
Stock outstanding after the dividend, subdivision, distribution or split
(assuming the exercise or conversion of all Common Stock Equivalents issued or
issuable pursuant to such dividend, subdivision, distribution or split).

                                  (2)      In the event the Corporation should
at any time, or from time to time, after the Filing Date issue or sell any
Common Stock or Common Stock Equivalents for a consideration per share of
Common Stock (i) less than the Series A Conversion Price, then the Series A
Conversion Price shall be appropriately reduced to a price (calculated to the
nearest cent) determined by dividing an amount equal to (x) the sum of (A) the
number of shares of Common Stock outstanding immediately prior to such issue or
sale multiplied by the then existing Series A Conversion Price, plus (B) the
consideration received by the Corporation upon such issue or sale, by (y) the
total number of shares of Common Stock outstanding after such issue or sale,
(ii) less than the Series B Conversion Price, then the Series B Conversion
Price shall be appropriately reduced to a price (calculated to the nearest
cent) determined by dividing an





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amount equal to (x) the sum of (A) the number of shares of Common Stock
outstanding immediately prior to such issue or sale multiplied by the then
existing Series B Conversion Price, plus (B) the consideration received by the
Corporation upon such issue or sale, by (y) the total number of shares of
Common Stock outstanding after such issue or sale, (iii) less than the Series C
Conversion Price, then the Series C Conversion Price shall be appropriately
reduced to a price (calculated to the nearest cent) determined by dividing an
amount equal to (x) the sum of (A) the number of shares of Common Stock
outstanding immediately prior to such issue or sale multiplied by the then
existing Series C Conversion Price, plus (B) the consideration received by the
corporation upon such issue or sale, by (y) the total number of shares of
Common Stock outstanding after such issue or sale and (iv) less than the Series
D Conversion Price, then the Series D Conversion Price shall be appropriately
reduced to a price (calculated to the nearest cent) determined by dividing an
amount equal to (x) the sum of (A) the number of shares of Common Stock
outstanding immediately prior to such issue or sale multiplied by the then
existing Series D Conversion Price, plus (B) the consideration received by the
corporation upon such issue or sale, by (y) the total number of shares of
Common Stock outstanding after such issue or sale.  No adjustment of the Series
A Conversion Price, the Series B Conversion Price, the Series C Conversion
Price or the Series D Conversion Price, as applicable, shall be made in an
amount less than $.01 per share, but such lesser adjustment shall be carried
forward and





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shall be made at the time that such adjustment together with any future
adjustments to the Series A Conversion Price, the Series B Conversion Price,
the Series C Conversion Price or the Series D Conversion Price, as applicable,
shall amount to $.01 per share or more.

                                  (3)      If the number of shares of Common
Stock outstanding at any time after the Filing Date is decreased by a
combination (by reverse stock split or otherwise) of the outstanding shares of
Common Stock, then, following the record date of such combination, (A) the
Series A Conversion Price shall be appropriately increased to an amount equal
to the Series A Conversion Price in effect on the record date (or the date of
such combination if no record date is fixed) times a fraction, the numerator of
which shall be the number of shares outstanding before the combination and, the
denominator of which shall be the number of shares outstanding after the
combination, (B) the Series B Conversion Price shall be appropriately increased
to an amount equal to the Series B Conversion Price in effect on the record
date (or the date of such combination if no record date is fixed) times a
fraction, the numerator of which shall be the number of shares outstanding
before the combination and, the denominator of which shall be the number of
shares outstanding after the combination, (C) the Series C Conversion Price
shall be appropriately increased to an amount equal to the Series C Conversion
Price in effect on the record date (or the date of such combination if no
record date is fixed) times a fraction, the numerator of which shall be the
number of shares outstanding before the





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combination and, the denominator of which shall be the number of shares
outstanding after the combination and (D) the Series D Conversion Price shall
be appropriately increased to an amount equal to the Series D Conversion Price
in effect on the record date (or the date of such combination if no record date
is fixed) times a fraction, the numerator of which shall be the number of
shares outstanding before the combination and, the denominator of which shall
be the number of shares outstanding after the combination.

                          (iv)    The issuance of certificates for shares of
Common Stock upon conversion of Series Preferred Stock, shall be made without
charge to the holders thereof for any issuance tax in respect thereof, provided
that the Corporation shall not be required to pay any tax which may be payable
in respect of any transfer involved in the issuance and delivery of any
certificate in a name other than that of the holder of the Series Preferred
Stock which is being converted.

                          (v)     The Corporation will at no time close its
transfer books against the transfer of any Series Preferred Stock or of any
shares of Common Stock issued or issuable upon the conversion of any shares of
Series Preferred Stock, in any manner which interferes with the timely
conversion of such Series Preferred Stock, except as may otherwise be required
to comply with applicable securities laws.

                          (vi)    As used in this Paragraph 3, the term "Common
Stock" shall mean and include the Corporation's authorized Common Stock, par
value





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$.001 per share, as constituted on the Filing Date, and shall also include any
capital stock of any class of the Corporation thereafter authorized which shall
neither be limited to a fixed sum or percentage in respect of the rights of the
holders thereof to participate in dividends nor be entitled to a preference in
the distribution of assets upon the voluntary or involuntary liquidation,
dissolution or winding up of the Corporation; provided that the shares of
Common Stock receivable upon conversion of shares of Series Preferred Stock
shall include only shares designated as Common Stock of the Corporation on the
Filing Date, or in case of any reorganization or reclassification of the
outstanding shares thereof, the stock, securities or assets to be issued in
exchange for such Common Stock pursuant thereto.

                          (vii)    Liquidity Event Adjustments.

                                        (A)     Series A Preferred Stock.  The
Conversion Price of the Series A Preferred Stock shall be subject to adjustment
upon the occurrence of a Liquidity Event (as defined below), if the Series A
Conversion Value Per Share (as defined below) on the Event Date (as defined
below), is less than the Series A Target Value Per Share (as defined below) on
the Event Date.  In such case, the Conversion Price of the Series A Preferred
Stock shall be reduced such that, immediately after giving effect to such
reduction, the Series A Conversion Value Per Share equals the Series A Target
Value Per Share; provided, however, that the Conversion Price of the Series A
Preferred Stock shall not be reduced by more than Maximum Adjustment Amount (as
defined below);





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and, provided further, however, that the provisions of this subparagraph
3(vii)(A) shall be applied only to the first Liquidity Event following the
Series A Initial Issuance Date (as defined below).  No adjustment of the
Conversion Price of the Series A Preferred Stock shall be made in an amount
less than $.01 per share, but such lesser adjustment shall be carried forward
and shall be made at the time that such adjustment together with any
adjustments carried forward, shall amount to $.01 per share or more.

                                        (B)     Series B Preferred Stock.  The
Conversion Price of the Series B Preferred Stock shall be subject to adjustment
upon the occurrence of a Liquidity Event (as defined below), if the Series B
Conversion Value Per Share (as defined below) on the Event Date (as defined
below), is less than the Series B Target Value Per Share (as defined below) on
the Event Date.  In such case, the Conversion Price of the Series B Preferred
Stock shall be reduced such that, immediately after giving effect to such
reduction, the Series B Conversion Value Per Share equals the Series B Target
Value Per Share; provided, however, that the Conversion Price of the Series B
Preferred Stock shall not be reduced by more than Maximum Adjustment Amount (as
defined below); and, provided further, however, that the provisions of this
subparagraph 3(vii)(B) shall be applied only to the first Liquidity Event
following the Series B Initial Issuance Date (as defined below).  No adjustment
of the Conversion Price of the Series B Preferred Stock shall be made in an
amount less than $.01 per share, but such lesser adjustment shall be carried
forward and





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shall be made at the time that such adjustment together with any adjustments
carried forward, shall amount to $.01 per share or more.

         For purposes of this Paragraph 3, the following terms shall have the
following meanings:

                                  (1)      Series A Conversion Value Per Share:
the Fair Market Value Per Share (as defined below) of Common Stock multiplied
by the number of shares of Common Stock issuable upon the conversion of one
share of Series A Preferred Stock or Series B Preferred Stock, determined
pursuant to subparagraph 3(b)(i).

                                  (2)      Series B Conversion Value Per Share:
the Fair Market Value Per Share (as defined below) of Common Stock multiplied
by the number of shares of Common Stock issuable upon the conversion of one
share of Series B Preferred Stock, determined pursuant to subparagraph 3(b)(i).

                                  (3)      Event Date: in the case of (a) an
Initial Public Offering (as defined in subparagraph 3(b)(vii)(5) hereof), the
later of (x) the date that such Initial Public Offering is declared effective
by the Securities and Exchange Commission, and (y) the date on which the
Corporation and the lead underwriter establish the public offering price, and
(b) a Sale of the Corporation or Liquidation, the earlier of (x) the date upon
which all director, stockholder, court or governmental approvals which are
necessary conditions precedent to such transaction have been obtained and (y)
the date upon which such transaction is consummated.





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                                  (4)      Fair Market Value Per Share: in the
case of (a) an Initial Public Offering, the public offering price per share of
the Corporation's Common Stock (before deducting underwriting compensation and
discounts and offering expenses); (b) a Sale of the Corporation, the value of
the consideration received by the Corporation and its stockholders in
connection with such sale of the Corporation, divided by the number of shares
of Common Stock outstanding on the Liquidity Date (assuming the conversion of
all of the outstanding Series A Preferred Stock and Series B Preferred Stock);
provided, however, that in the event of a Sale of the Corporation accomplished
through the transfer of capital stock which results in the transfer of less
than all of the Corporation's capital stock, the Fair Market Value Per Share
shall equal the value of the consideration received by the Corporation and its
stockholders in connection with such sale of the Corporation, divided by the
number of shares of the Corporation's capital stock acquired by the transferee;
and (c) a Liquidation, the value of all cash, stock and other property
available for distribution to the stockholders of the Corporation, divided by
the number of shares of Common Stock outstanding (assuming the conversion of
all of the convertible securities).

                                  (5)      Liquidity Event: any of (a) a sale
by the Corporation of securities in an underwritten public offering pursuant to
a registration statement filed pursuant to the Securities Act of 1933, as
amended,





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and declared effective by the Securities and Exchange Commission (an "Initial
Public Offering"); (b) a Sale of the Corporation; or (c) a Liquidation.

                                  (6)      Series A Initial Issuance Date:
November 5, 1993, the date that shares of Series A Preferred Stock were first
issued by the Corporation.

                                  (7)      Series B Initial Issuance Date:
September 16, 1994, the date that shares of Series B Preferred Stock were first
issued by the Corporation.

                                  (8)      Maximum Adjustment: a reduction in
the Conversion Price which results in the number of shares of Common Stock
issuable upon conversion of one share of Series A Preferred Stock or Series B
Preferred Stock increasing by .16875 shares (subject to adjustment for stock
splits, stock dividends, combinations and similar recapitalizations).

                                  (9)      Series A Target Value Per Share: the
amount which would be realized if the holder of a share of Series A Preferred
Stock had invested Four Dollars and Fifty Cents ($4.50) on the Series A Initial
Issuance Date at a 40% compounded annual rate of return.

                                  (10)     Series B Target Value Per Share: the
amount which would be realized if the holder of a share of Series B Preferred
Stock had invested Four Dollars and Fifty Cents ($4.50) on the Series B Initial
Issuance Date at a 40% compounded annual rate of return.





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<PAGE>   22

                          (viii)  Other Distributions.  In the event the
Corporation shall declare a distribution payable in securities of other
persons, evidences of indebtedness issued by the Corporation or other persons,
assets (excluding cash dividends) or options or rights not otherwise referred
to in subparagraph 3(b)(iii), then, in each such case, the holders of the
Series Preferred Stock shall be entitled to a proportionate share of any such
distribution as though they were the holders of the number of shares of Common
Stock of the Corporation into which their shares of Series Preferred Stock are
convertible as of the record date fixed for the determination of the holders of
Common Stock of the Corporation entitled to receive such distribution.

                          (ix)    Recapitalizations.  In the case of a
recapitalization of the Corporation affecting its outstanding shares of Common
Stock, the Series Preferred Stock shall thereafter be convertible into the kind
and amount of shares of stock, other securities, or property receivable upon
such recapitalization by a holder of the number of shares of Common Stock into
which such Series Preferred Stock might have been converted immediately prior
to such recapitalization.





                          (x)     Adjustment for Sale of Corporation.  In the
case of a Sale of the Corporation or a proposed reorganization of the
Corporation or a proposed reclassification of the capital stock of the
Corporation (except a





                                     - 22 -
<PAGE>   23

transaction for which provision for adjustment is otherwise made in this
Paragraph 3(b)), each share of Series Preferred Stock shall thereafter be
convertible into the number of shares of stock or other securities or property
to which a holder of the number of shares of Common Stock of the Corporation
deliverable upon conversion of such Series Preferred Stock would have been
entitled upon such Sale of the Corporation, reorganization or reclassification;
and, in any such case, appropriate adjustment (as determined by the Board of
Directors) shall be made in the application of the provisions herein set forth
with respect to the rights and interest thereafter of the holders of the Series
Preferred Stock, to the end that the provisions set forth herein (including
provisions with respect to changes in and other adjustments of the applicable
conversion price) shall thereafter be applicable, as nearly as reasonably may
be, in relation to any shares of stock or other property thereafter deliverable
upon the conversion of the Series Preferred Stock.  The Corporation shall not
effect any such Sale of the Corporation unless prior to or simultaneously with
the consummation thereof the successor corporation or purchaser, as the case
may be, shall assume by written instrument the obligation to deliver to the
holders of the Series Preferred Stock such shares of stock, securities or
assets as, in accordance with the foregoing provisions, each such holder is
entitled to receive.

                          (xi)    No Impairment.  The Corporation will not, by
amendment of its Certificate of Incorporation or through any reorganization,





                                     - 23 -
<PAGE>   24

recapitalization, transfer of assets, consolidation, merger, dissolution, issue
or sale of securities or any other voluntary action, avoid or seek to avoid the
observance or performance of any of the terms to be observed or performed
hereunder by the Corporation, but will at all times in good faith assist in the
carrying out of all the provisions of this Paragraph 3 and in the taking of all
such action as may be necessary or appropriate in order to protect the
Conversion Rights of the holders of the Series Preferred Stock against
impairment.

                          (xii)   No Fractional Shares and Certificates as to
Adjustment.

                                  (1)      No fractional shares shall be issued
upon conversion of the Series Preferred Stock and the number of shares of
Common Stock to be issued shall be rounded up to the nearest whole share.
Whether or not fractional shares are issuable upon such conversion shall be
determined on the basis of the total number of shares of Series Preferred Stock
the holder is at the time converting into Common Stock and the number of shares
of Common Stock issuable upon such aggregate conversion.

                                  (2)      Upon the occurrence of each
adjustment or readjustment of the Series A Conversion Price, the Series B
Conversion Price, the Series C Conversion Price and/or the Series D Conversion
Price, as applicable, pursuant to this Paragraph 3, the Corporation, at its
expense, shall promptly compute such adjustment or readjustments in accordance
with the terms hereof and prepare and furnish to each holder of Series
Preferred Stock, as





                                     - 24 -
<PAGE>   25

applicable, a certificate setting forth such adjustment or readjustment and
showing in detail the facts upon which such adjustment or readjustment is
based. The Corporation shall, upon the written request at any time of any
holder of Series Preferred Stock furnish or cause to be furnished to such
holder a like certificate setting forth (a) such adjustment and readjustment,
(b) the applicable conversion price at the time in effect, and (c) the number
of shares of Common Stock and the amount, if any, of other property which at
the time would be received upon the conversion of a share of Series Preferred
Stock, as applicable.

                          (xiii) Notices of Record Date.  In the event of any
taking by the Corporation of a record of the holders of any class of securities
for the purpose of determining the holders thereof who are entitled to receive
any dividend or other distribution, any right to subscribe for, purchase or
otherwise acquire any shares of stock of any class or any other securities or
property, or to receive any other right, the Corporation shall mail to each
holder of Series Preferred Stock, at least twenty (20) days prior to the date
specified therein, a notice specifying the date on which any such record is to
be taken for the purpose of such dividend, distribution or right and the amount
and character of such dividend, distribution or right.

                          (xiv)   Reservation of Stock Issuable Upon
Conversion.  The Corporation shall at all times reserve and keep available out
of its authorized but unissued shares of Common Stock, solely for the purpose
of effecting the





                                     - 25 -
<PAGE>   26

conversion of the shares of Series Preferred Stock such number of its shares of
Common Stock as shall from time to time be sufficient to effect the conversion
of all outstanding shares of Series Preferred Stock, and if at any time the
number of authorized but unissued shares of Common Stock shall not be
sufficient to effect the conversion of all then outstanding shares of the
Series Preferred Stock, in addition to such other remedies as shall be
available to the holders of such Series Preferred Stock, the Corporation will
take such corporate action as may, in the opinion of its counsel, be necessary
to increase its authorized but unissued shares of Common Stock to such number
of shares as shall be sufficient for such purposes.

         4.      Automatic Conversion.

                 (a)      Immediately upon the closing of the sale of shares of
Common Stock in a bona fide, firm commitment, underwritten public offering
pursuant to an effective registration statement under the Securities Act of
1933, as amended, resulting in at least $20,000,000 of gross proceeds to the
Corporation (before deducting underwriting discount and commissions and
offering expenses) and reflecting a Corporation Valuation (as defined below) of
at least $75,000,000 (a "Qualified Public Offering"), (i) each share of Series
A Preferred Stock then outstanding shall automatically be converted into Common
Stock at the then effective Series A Conversion Price pursuant to Paragraph 3





                                     - 26 -
<PAGE>   27

hereof, (ii) each share of Series B Preferred Stock then outstanding shall
automatically be converted into Common Stock at the then effective Series B
Conversion Price pursuant to Paragraph 3 hereof, (iii) each share of Series C
Preferred Stock then outstanding shall automatically be converted into Common
Stock at the then effective Series C Conversion Price pursuant to Paragraph 3
hereof, and (iv) each share of Series D Preferred Stock then outstanding shall
automatically be converted into Common Stock at the then effective Series D
Conversion Price, pursuant to Paragraph 3 hereof.

                 The term "Corporation Valuation" means, with respect to any
public offering of Common Stock, the amount obtained by multiplying the total
number of shares of Common Stock outstanding immediately prior to such public
offering (assuming the conversion, exchange or exercise of all securities
convertible into, or exchangeable or exercisable for, any shares of Common
Stock) multiplied by the per share offering price for such public offering.

                 (b)      All holders of record of shares of Series Preferred
Stock will be given at least 10 days' prior written notice of the date fixed
and the place designated for mandatory conversion of all such shares of Series
Preferred Stock pursuant to this Paragraph 4. Such notice will be sent by first
class or registered mail, postage prepaid, to each record holder of Series
Preferred Stock at such holder's address last shown on the records of the
transfer agent for the Series Preferred Stock (or the records of the
Corporation, if it serves as its own transfer agent).  On or before the date
fixed for conversion, each





                                     - 27 -
<PAGE>   28

holder of shares of Series Preferred Stock shall surrender his or its
certificate or certificates for all such shares to the Corporation at the place
designated in such notice, and shall thereafter receive certificates for the
number of shares of Common Stock to which such holder is entitled pursuant to
this Paragraph 4.  On the date fixed for conversion, all rights with respect to
the share of Series Preferred Stock so converted, including the rights, if any,
to receive notices and vote, will terminate, except only the rights of the
holders thereof upon surrender of their certificate or certificates therefor,
to receive certificates for the number of shares of Common Stock into which
such shares of Series Preferred Stock has been converted, and payment of any
accrued but unpaid dividends thereon.  If so required by the Corporation,
certificates surrendered for conversion shall be endorsed or accompanied by
written instrument or instruments of transfer, in form satisfactory to the
Corporation, duly executed by the registered holder or by his or its attorney
duly authorized in writing.  As soon as practicable after the date of such
mandatory conversion and the surrender of the certificate or certificates for
the shares of Series Preferred Stock so converted, the Corporation shall cause
to be issued and delivered to such holder, or on his or its written order, a
certificate or certificates for the number of full shares of Common Stock
issuable on such conversion in accordance with the provisions hereof and as
provided in subparagraph 3(b)(xii) in respect of any fraction of a share of
Common Stock otherwise issuable upon such conversion.





                                     - 28 -
<PAGE>   29

                 (c)      All certificates evidencing shares of Series
Preferred Stock which are required to be surrendered for conversion in
accordance with the provisions hereof shall, from and after the date such
certificates are so required to be surrendered, be deemed to have been retired
and canceled and the shares of Series Preferred Stock represented thereby
converted into Common Stock for all purposes, notwithstanding the failure of
the holder or holders thereof to surrender such certificates on or prior to
such date.  The Corporation may thereafter take such appropriate action as may
be necessary to reduce the authorized Series Preferred Stock accordingly.

         5.      Protective Provisions.

                 (a)      So long as shares of Series A Preferred Stock are
outstanding, the Corporation shall not without first obtaining the approval (by
vote or written consent, as provided by law) of the holders of at least a
majority of the then outstanding shares of Series A Preferred Stock:

                          (i)     alter or change the rights, preferences or
privileges of the shares of Series A Preferred Stock or otherwise amend this
Certificate of Incorporation so as to affect adversely the shares of Series A
Preferred Stock; or

                          (ii)    increase the authorized number of shares of
Series A Preferred Stock; or

                          (iii)   create or designate any new class or series
of stock (A) having a preference over, or being on a parity with, the Series A
Preferred





                                     - 29 -
<PAGE>   30

Stock with respect to dividends or upon liquidation, (B) having rights similar
to any of the rights of the Series A Preferred Stock under Paragraph 3 hereof
or (C) convertible into any such class or series of stock; or

                          (iv)    cause the Corporation to be liquidated or
dissolved, either voluntarily or involuntarily; or



                          (v)     do any act or thing which would result in
taxation of the holders of shares of the Series A Preferred Stock under Section
305 of the Internal Revenue Code of 1986, as amended (or any comparable
provision of the Internal Revenue Code as hereafter from time to time amended);
or

                          (vi)    Consolidate or merge into or with any other
entity or entities or sell, lease, abandon, transfer or otherwise dispose of
all or substantially all its assets; or

                          (vii)   purchase or set aside any sums for the
purchase of, or pay any dividend or make any distribution on, any shares of
stock other than the Series A Preferred Stock, except for dividends or other
distributions payable on the Common Stock solely in the form of additional
shares of Common Stock and except for the purchase of shares of Common Stock
from former employees of the Corporation who acquired such shares directly from
the Corporation, if each such purchase is made pursuant to contractual rights
held by the Corporation relating to the termination of employment of such
former employee and the purchase price





                                     - 30 -
<PAGE>   31

does not exceed the original issue price paid by such former employee to the
Corporation for such shares; or

                          (viii) redeem or otherwise acquire any shares of
Series A Preferred Stock pursuant to a purchase offer made pro rata to all
holders of the shares of Series A Preferred Stock on the basis of the aggregate
number of outstanding shares of Series A Preferred Stock then held by each such
holder.

                 (b)      So long as shares of Series B Preferred Stock are
outstanding, the Corporation shall not without first obtaining the approval (by
vote or written consent, as provided by law) of the holders of at least a
majority of the then outstanding shares of Series B Preferred Stock:

                          (i)     alter or change the rights, preferences or
privileges of the shares of Series B Preferred Stock or otherwise amend this
Certificate of Incorporation so as to affect adversely the shares of Series B
Preferred Stock; or

                          (ii)    increase the authorized number of shares of 
Series B Preferred Stock; or

                          (iii)   create or designate any new class or series
of stock, other than the Series A Preferred Stock, (A) having a preference
over, or being on a parity with, the Series B Preferred Stock with respect to
dividends or upon liquidation, (B) having rights similar to any of the rights
of the Series B Preferred Stock under Paragraph 3 hereof or (C) convertible
into any such class or series of stock; or





                                     - 31 -
<PAGE>   32

                          (iv)    redeem or otherwise acquire any shares of
Series B Preferred Stock pursuant to a purchase offer made pro rata to all
holders of the shares of Series B Preferred Stock on the basis of the aggregate
number of outstanding shares of Series B Preferred Stock then held by each such
holder.

                 (c)      So long as shares of Series C Preferred Stock (or
securities convertible into, or exchangeable or exercisable for, shares of
Series C Preferred Stock ("Series C Equivalents")) are outstanding, the
Corporation shall not without first obtaining the approval (by vote or written
consent, as provided by law) of the holders of at least a majority of the then
outstanding shares of Series C Preferred Stock (assuming conversion exchange or
exercise of all Series C Equivalents):

                          (i)     alter or change the rights, preference or
privileges of the shares of Series C Preferred Stock or otherwise amend this
Certificate of Incorporation so as to affect adversely the shares of Series C
Preferred Stock; or

                          (ii)    increase the authorized number of shares of
Series C Preferred Stock; or

                          (iii)   create or designate, or authorize the
issuance of, any new class or series of stock (A) ranking senior or having a
preference over, or being on a parity with, the Series C Preferred Stock with
respect to dividends or upon liquidation, (B) having rights similar to any
rights of the Series C





                                     - 32 -
<PAGE>   33

Preferred Stock under Paragraph 3 hereof or Paragraph 6 hereof, or (C)
convertible into any such class or series of stock.

                 (d)      So long as shares of Series D Preferred Stock(or
securities convertible into, or exchangeable or exercisable for, Series D
Preferred Stock ("Series D Equivalents")) are outstanding, the Corporation
shall not without first obtaining the approval (by vote or written consent, as
provided by law) of the holders of at least a majority of the then outstanding
shares of Series D Preferred Stock (assuming conversion, exchange or exercise
of all Series D Equivalents):

                          (i)     alter or change the rights, preference or
privileges of the shares of Series D Preferred Stock or otherwise amend this
Certificate of Incorporation so as to affect adversely the shares of Series D
Preferred Stock; or

                          (ii)    increase the authorized number of shares of
Series D Preferred Stock; or

                          (iii)   create or designate, or authorize the
issuance of, any new class or series of stock (A) ranking senior or having a
preference over, or being on a parity with, the Series D Preferred Stock with
respect to dividends or upon liquidation, (b) having rights similar to any
rights of the Series D Preferred Stock under Paragraph 3 hereof or Paragraph 6
hereof or (C) convertible into any such class or series of stock.





                                     - 33 -
<PAGE>   34

                 (e)      In the event the Corporation should at any time, or
from time to time, after the Filing Date issue or sell any shares of Series A
Preferred Stock or Series B Preferred Stock for a consideration per share less
than Four Dollars and Fifty Cents ($4.50) (a "Subsequent Offering"), (i) each
holder of Series A Preferred Stock shall, upon the consummation of such
Subsequent Offering, be entitled to receive, without charge, and the
Corporation shall issue to each holder of Series A Preferred Stock, a number of
additional shares of Series A Preferred Stock (rounded to the nearest whole
number of shares of Series A Preferred Stock) such that, after receipt of such
additional shares of Series A Preferred Stock, such holder will hold an
aggregate number of shares of Series A Preferred Stock equal to the number of
shares of Series A Preferred Stock that such holder would have received if such
holder had invested in the Subsequent Offering an amount equal to Four Dollars
and Fifty Cents ($4.50) multiplied by the number of shares of Series A
Preferred Stock held by such holder immediately prior to consummation of the
Subsequent Offering, and (ii) each holder of Series B Preferred Stock shall,
upon the consummation of such Subsequent Offering, be entitled to receive,
without charge, and the Corporation shall issue to each holder of Series B
Preferred Stock, a number of additional shares of Series B Preferred Stock
(rounded to the nearest whole number of shares of Series B Preferred Stock)
such that, after receipt of such additional shares of Series B Preferred Stock,
such holder will hold an aggregate number of shares of Series B Preferred Stock
equal to the number of shares of Series





                                     - 34 -
<PAGE>   35

B Preferred Stock that such holder would have received if such holder had
invested in the Subsequent Offering an amount equal to Four Dollars and Fifty
Cents ($4.50) multiplied by the number of shares of Series B Preferred Stock
held by such holder immediately prior to consummation of the Subsequent
Offering; provided, that upon the issuance of any such additional shares of
Series Preferred Stock pursuant to this Paragraph 5(e) of this FOURTH Amended
and Restated Certificate of Incorporation shall, without any further action
required by the Board of Directors or stockholders of the Corporation, be
amended as follows: the "Four Dollars and Fifty Cents ($4.50)" amount set forth
with respect to shares of Series A Preferred Stock and Series B Preferred Stock
in Article Fourth, Paragraphs 2(a), 3(b)(i) and 3(b)(vii) and this Paragraph
5(b) shall be reduced to the amount of consideration per share of Series
Preferred Stock for which shares of Series Preferred Stock are sold in the
Subsequent Offering.

         6.      General Voting Rights.

                 (a)      Common Stock.  Each holder of Common Stock shall be
entitled to one vote for each share of Common Stock held.  Except as required
by law or as otherwise set forth in Paragraph 5 or 6 hereof, the holders of
shares of Series Preferred Stock and Common Stock shall vote together and not
as separate classes.  Until a Qualified Public Offering, the holders of the
Common Stock along with the holders of Series B Preferred Stock shall together
vote as a class to elect the members of the Board of Directors (the "Common
Directors"),





                                     - 35 -
<PAGE>   36

other than the Series A Directors and Designated Series C Directors (each as
defined below).

                 (b)      Series A Preferred Stock.  The holder of each share
of Series A Preferred Stock shall be entitled to vote on all matters and shall
be entitled to the number of votes equal to the largest number of full shares
of Common Stock into which such shares of Series A Preferred Stock could be
converted, pursuant to the provisions of Paragraph 3 hereof at the record date
for the determination of the shareholders entitled to vote on such matters or,
if no such record date is established, at the date such vote is taken or any
written consent of shareholders is solicited; provided, however, that the
holders of Series A Preferred Stock shall not be entitled to vote on any matter
relating to the election of the Common Directors and the Designated Series C
Directors.  Until a Qualified Public Offering, the holders of the Series A
Preferred Stock shall be entitled to vote as a class to elect two persons to
the Corporation's Board of Directors (the "Series A Directors").

                 At any meeting (or in a written consent in lieu thereof) held
for the purpose of electing directors, the presence in person or by proxy (or
the written consent) of the holders of a majority of the shares of Series A
Preferred Stock then outstanding shall constitute a quorum of the Series A
Preferred Stock for the election of the Series A Directors.  A vacancy in any
directorship held by a Series A Director shall be filled only by vote or
written consent of the holders of the Series A Preferred Stock.  Series A
Directors may





                                     - 36 -
<PAGE>   37

be removed only by vote or written consent of the holders of the Series A
Preferred Stock.

                 (c)      Series B Preferred Stock.  The holder of each share
of Series B Preferred Stock shall be entitled to vote on all matters and shall
be entitled to the number of votes equal to the largest number of full shares
of Common Stock into which such shares of Series B Preferred Stock could be
converted, pursuant to the provisions of Paragraph 3 hereof, at the record date
for the determination of the shareholders entitled to vote on such matters or,
if no such record date is established, at the date such vote is taken or any
written consent of shareholders is solicited; provided, however, that the
holders of Series B Preferred Stock shall not be entitled to vote on any matter
relating to the election of the Series A Directors and the Designated Series C
Directors.

                 (d)      Series C Preferred Stock.  The holder of each share
of Series C Preferred Stock shall be entitled to vote on all matters and shall
be entitled to the number of votes equal to the largest number of full shares
of Common Stock into which such shares of Series C Preferred Stock could be
converted, pursuant to the provisions of Paragraph 3 hereof, at the record date
for the determination of the shareholders entitled to vote on such matters or,
if no such record date is established, at the date such vote is taken or any
written consent of shareholders is solicited; provided, however, that the
holders of Series C Preferred Stock shall not be entitled to vote on any
matters relating to (i) the election of the Series A Directors and (ii) prior
to a Termination





                                     - 37 -
<PAGE>   38


Event, the election of the Common Directors.  Until a Qualified Public
Offering, the holders of Series C Preferred Stock together with the holders of
Series D Preferred Stock shall be entitled to vote as a class to elect the
Designated Series C Directors in accordance with Paragraph 6(f) hereof.

                 (e)      Series D Preferred Stock.  The holder of each share
of Series D Preferred Stock shall be entitled to vote on all matters and shall
be entitled to the number of votes equal to the largest number of full shares
of Common Stock into which such shares of Series D Preferred Stock could be
converted, pursuant to the provisions of Paragraph 3 hereof, at the record date
for the determination of the shareholders entitled to vote on such matters or,
if no such record date is established, at the date such vote is taken or any
written consent of shareholders is solicited.  Until a Qualified Public
Offering, the holders of Series D Preferred Stock together with the holders of
Series C Preferred Stock shall be entitled to vote as a class to elect the
Designated Series C Directors in accordance with Paragraph 6(f) hereof;
provided, however, that the holders of the Series D Preferred Stock shall not
be entitled to vote on any matters relating to (i) the election of the Series A
Directors and (ii) prior to a Termination Event, the election of the Common
Directors.

                 (f)      Designated Series C Directors.

                          (i)     Prior to a Qualified Public Offering, the
holders of Series C Preferred Stock and Series D Preferred Stock shall be
entitled to vote as a class to elect (A) two persons to the Corporation's Board
of Directors so





                                     - 38 -
<PAGE>   39

long as GSCP together with all partnerships, corporations, trusts or other
organizations which are controlled by, control or are under common control with
GSCP or one or more of the then current, former or future partners of GSCP
(collectively, the "GS Parties"), together with any Exempt Transferees (as
defined below), have not sold or otherwise transferred to one or more third
parties (other than pursuant to any Exempt Transfers (as defined below)) an
amount of shares of Series C Preferred Stock and/or Series D Preferred Stock
(and/or Common Stock issued upon conversion thereof) equal to or greater than
50% of the Original Shares (as defined below), (B) one person to the
Corporation's Board of Directors from and after such time as the GS Parties,
together with any Exempt Transferees, have sold or otherwise transferred to one
or more third parties (other than pursuant to any Exempt Transfers) an amount
of shares of Series C Preferred Stock and/or Series D Preferred Stock (and/or
Common Stock issued upon conversion thereof) equal to or greater than 50% of
the Original Shares.  Each person elected to be a director by the holders of
Series C Preferred Stock and Series D Preferred Stock, pursuant to this
paragraph, shall be referred to as a "Designated Series C Director".

                          (ii)    The holders of Series C Preferred Stock and
Series D Preferred Stock shall vote together as a class together with Series A
Preferred Stock, Series B Preferred Stock and Common Stock to elect all members
of the Board of Directors (except, prior to a Qualified Public Offering, the
Series A Directors) from and after such time as the GS Parties, together with
any Exempt





                                     - 39 -
<PAGE>   40

Transferees, beneficially own less than 10% of the outstanding Common Stock of
the Corporation (assuming conversion, exercise and exchange of all Common Stock
Equivalents) (other than pursuant to the issuance of additional shares of
Common Stock or Common Stock Equivalents by the Corporation other than in
connection with the private placement of the Series C Preferred Stock and the
exercise of the Warrants) (a "Termination Event").

                          (iii) The term "Original Shares" means the aggregate
number of shares of Preferred Stock purchased by the GS Parties in connection
with the private placement of the Series C Securities together with any shares
of Preferred Stock issued upon exercise of Preferred Stock Warrants (as
adjusted for stock splits, stock dividends, recapitalizations and similar
events).  The term "Exempt Transfer" means a sale or transfer to a
Non-Competitor in a single transaction, or a series of related transactions, of
(A) an amount of shares of Series C Preferred Stock and/or Series D Preferred
Stock (and/or Common Stock issued upon conversion thereof) equal to 50% or more
of the Original Shares or (B) all of the capital stock (and securities
convertible into, or exercisable or exchangeable, for capital stock) of the
Corporation held by the GS Parties.  The term "Non-Competitor" means any person
that is not a direct competitor of the Corporation in the United States in the
business of commercializing breast cancer detection technology (other than
current technologies (or any variation thereof) utilized for such detection).
The term "Exempt Transferee" means any transferee pursuant to an Exempt
Transfer.  For purposes of the calculations





                                     - 40 -
<PAGE>   41

under this Paragraph 6(f), shares of Common Stock obtained upon conversion of
shares of Preferred Stock which are sold or transferred shall be treated as the
sale or transfer of the amount of shares of Preferred Stock  converted in
respect thereof.

                 (iv)     At any meeting (or in a written consent in lieu
thereof) held for the purpose of electing directors, the presence in person or
by proxy (or the written consent) of the holders of a majority of the shares of
Series C Preferred Stock and Series D Preferred Stock then outstanding shall
constitute a quorum for the election of the Designated Series C Directors.  For
so long as the GS Parties own a majority of the then outstanding shares of
Series C Preferred Stock and/or Series D Preferred Stock, a vacancy in any
directorship held or permitted to be held by a Designated Series C Director may
be filled by (i) the vote of the remaining Designated Series C Director, if
any, or (ii) by a majority of the then outstanding shares of Series C Preferred
Stock and/or Series D Preferred Stock.  Subject to Paragraph 6(f)(i) hereof, at
all other times, a vacancy in any directorship held or permitted to be held by
a Designated Series C Director shall be filled only by vote or written consent
of the holders of the Series C Preferred Stock and Series D Preferred Stock.
Designated Series C Directors may be removed only by vote or written consent of
the holders of the Series C Preferred Stock and Series D Preferred Stock.

         7.      Notices.





                                     - 41 -
<PAGE>   42

                 Any notice required by these provisions to be given to the
holders of shares of Series Preferred Stock shall be deemed given if sent by
U.S. certified mail, return receipt requested and postage prepaid, and
addressed to each holder of record at his address appearing on the books of the
Corporation. The date of any such notice shall be deemed to be the date on
which it is sent.

         FIFTH.  The Board of Directors is authorized, subject to limitations
prescribed by law and provisions of Article FOURTH, to provide for the issuance
of additional shares of Preferred Stock in series, and by filing a certificate
pursuant to the applicable law of the State of Delaware, to establish from time
to time the number of shares to be included in each such series and to fix the
designation, powers, preferences and rights of the shares of each such series
and the qualifications, limitations or restrictions thereof.

                 The authority of the Board with respect to each series shall
include but not be limited to, determination of the following:

                 (a)      The number of shares constituting that series and the
distinctive designation of that series;

                 (b)      The dividend rate on the shares of that series,
whether dividends shall be cumulative, and, if so, from which date or dates,
and the relative rights of priority, if any, of payment of dividend on shares
of that series;

                 (c)      Whether that series shall have voting rights, in
addition to the voting rights provided by law, and, if so, the terms of such
voting rights;





                                     - 42 -
<PAGE>   43

                 (d)      Whether that series shall have conversion privileges,
and, if so, the terms and conditions of such conversion, including provision
for adjustment of the conversion rate in such events as the Board of Directors
shall determine;

                 (e)      Whether or not the shares of that series shall be
redeemable, and, if so, the terms and conditions of such redemption, including
the date or date upon or after which they shall be redeemable, which amount may
vary under different conditions and at different redemption dates;

                 (f)      Whether that series shall have a sinking fund for the
redemption or purchase shares of that series, and, if so the terms and amount
of such sinking fund;

                 (g)      The rights of the shares of that series in the event
of voluntary or involuntary liquidation, dissolution or winding up of the
corporation, and the relative rights of priority, if any, of payment of shares
of that series; and

                 (h)      Any other relative rights, preferences and
limitations of that series.


             SIXTH.       Election of directors need not be by written ballot.

             SEVENTH.     The Board of Directors is authorized to adopt, amend,
or repeal By-Laws of the Corporation.





                                     - 43 -
<PAGE>   44

             EIGHTH.      Any person who was or is a party or is threatened to 
be made a party to any threatened, pending, or completed action, suit, or 
proceeding, whether civil, criminal, administrative, or investigative (whether 
or not by or in the right of the Corporation) by reason of the fact that he is 
or was a director, officer, incorporator, employee or agent of the Corporation,
or is or was serving at the request of the Corporation as a director, officer,
incorporator, employee, partner, trustee, or agent of another corporation,
partnership, joint venture, trust, or other enterprise (including an employee
benefit plan), shall be entitled to be indemnified by the Corporation to the
full extent then permitted by law against expenses (including counsel fees and
disbursements), judgments, fines (including excise taxes assessed on a person
with respect to an employee benefit plan), and amounts paid in settlement
incurred by him in connection with such action, suit, or proceeding.  Such
right of indemnification shall inure whether or not the claim asserted is based
on matters which antedate the adoption of this Article EIGHTH. Such right of
indemnification shall continue as to a person who has ceased to be a director,
officer, incorporator, employee, partner, trustee, or agent and shall inure to
the benefit of the heirs and personal representatives of such a person. The
indemnification provided by this Article EIGHTH shall not be deemed exclusive
of any other rights which may be provided now or in the future under any
provision currently in effect or hereafter adopted of the By-Laws by any





                                     - 44 -
<PAGE>   45

agreement, by vote of stockholders, by resolution of disinterested directors,
by provision of law, or otherwise.

             NINTH.       No director of the Corporation shall be liable to the
Corporation or any of its stockholders for monetary damages for breach of
fiduciary duty as a director, provided that this provision does not eliminate
the liability of the director (i) for any breach of the director's duty of
loyalty to the Corporation or its stockholders, (ii) for acts or omissions not
in good faith or which involve intentional misconduct or a knowing violation of
law, (iii) under Section 174 of the DGCL, or (iv) for any transaction from
which the director derived an improper personal benefit.  For purposes the
prior sentence, the term "damages shall, to the extent permitted by law,
include without limitation, any judgment, fine, amount paid in settlement,
penalty, punitive damages, excise or other tax assessed with respect to an
employee benefit plan, or expense of any nature (including, without limitation,
counsel fees and disbursements).  Each person who serves as a director of the
Corporation while this Article NINTH is in effect shall be deemed to be doing
so in reliance on the provisions of this Article NINTH, and neither the
amendment or repeal of this Article NINTH, nor the adoption of any provision of
this Certificate of Incorporation inconsistent with this Article NINTH, shall
apply to or have any effect on the liability or alleged liability of any
director or the Corporation for, arising out of, based upon, or in connection
with any acts or omissions of such director occurring prior to such amendment,





                                     - 45 -
<PAGE>   46

repeal, or adoption of an inconsistent provision.  The provisions of this
Article NINTH are cumulative and shall be in addition to and independent of any
and all other limitations on or eliminations of the liabilities of directors of
the Corporation, as such, whether such limitations or eliminations arise under
or are created by any law, rule, regulation, by-law, agreement, vote of
shareholders or disinterested directors, or otherwise.

             TENTH.       Whenever a compromise or arrangement is proposed 
between this Corporation and its creditors or any class of them and/or between 
this Corporation and its stockholders or any class of them, any court of 
equitable jurisdiction within the State of Delaware may, on the application in 
a summary way of this Corporation or of any creditor or stockholder thereof or 
on the application of any receiver or receivers appointed for this Corporation 
under the provisions of Section 291 of the DGCL or on the application of 
trustees in dissolution or of any receiver or receivers appointed for this 
Corporation under the provisions of Section 279 of the DGCL, order a meeting 
of the creditors or class of creditors, and/or of the stockholders or class of
stockholders of this Corporation, as the case may be, to be summoned in such
manner as the said court directs.  If a majority in number representing
three-fourths in value of the creditors or class of creditors, and/or of the
stockholders or class of stockholders of this Corporation, as the case may be,
agree to any compromise or arrangement and to any reorganization of this
Corporation as a consequence of such compromise or arrangement, the said
compromise or arrangement and the





                                     - 46 -
<PAGE>   47

said reorganization shall, if sanctioned by the court to which the said
application has been made, be binding on all the creditors or class of
creditors, and/or on all the stockholders or class of stockholders, of this
Corporation, as the case may be, and also on this Corporation.





                                     - 47 -
<PAGE>   48



         IN WITNESS WHEREOF, I have made, signed, and sealed this Fourth
Amended and Restated Certificate of Incorporation this 3rd day of March, 1995.




ATTEST:                                     BIOFIELD CORP.

By: /s/ Michael R. Gavenchak                By: /s/ D. Carl Long
    ------------------------                   -----------------------
    Michael Gavenchak                          D. Carl Long
    Secretary                                  Chief Executive Officer






                                     - 48 -
<PAGE>   49



                          CERTIFICATE OF AMENDMENT

                                     OF

                         FOURTH AMENDED AND RESTATED

                        CERTIFICATE OF INCORPORATION

                                     OF

                               BIOFIELD CORP.


     Biofield Corp., a Delaware corporation (the "Corporation") does hereby
certify that, in accordance with the provisions of Section 242 of the General
Corporation Law of the State of Delaware, the following amendments to the Fourth
Amended and Restated Certificate of Incorporation of the Corporation were duly
adopted and approved by all of the directors of the Corporation by duly executed
unanimous written consent dated as of April 24, 1995, and by the holders of a
majority of each class of stock of the Corporation entitled to vote thereon by a
majority written consent dated as of April 24, 1995:

          (a) The FOURTH article of the Fourth Amended and Restated Certificate
     of Incorporation shall be amended to read as follows:

     FOURTH. The aggregate number of shares which the Corporation shall have the
authority to issue is thirty-seven million three hundred thousand (37,300,000)
shares, par value of $.001 per share, consisting of twenty-five million
($25,000,000) shares of Common Stock, par value $.001 per share; and twelve
million three hundred thousand (12,300,000) shares of Preferred Stock, par
value, $.001 per share. Such Preferred Stock shall consist of two million three
hundred fifty thousand (2,350,000) shares of Series A Convertible Preferred
Stock, par value $.001 per share (the "Series A Preferred Stock"); five hundred
thousand (500,000) shares of Series B Convertible


<PAGE>   50


Preferred Stock, par value $.001 per share (the "Series B Preferred Stock");
four million four hundred fifty thousand (4,450,000) shares of Series C
Convertible Preferred Stock, par value $.001 per share (the "Series C Preferred
Stock"); three million (3,000,000) shares of Series D Convertible Preferred
Stock, par value $.001 per share (the "Series D Preferred Stock"); and two
million (2,000,000) shares of such Preferred Stock, par value $.001 per share,
as may be established by the Board of Directors pursuant to Article FIFTH
hereof, subject to the protective provisions of Paragraph 5 of Article FOURTH
hereof. (The Series A Preferred Stock, the Series B Preferred Stock, the Series
C Preferred Stock and the Series D Preferred Stock are hereinafter collectively
referred to as the "Series Preferred Stock"); and

          (b) paragraph 3(b)(iii)(i)A of the Fourth Amended and Restated
     Certificate of Incorporation shall be amended to read as follows:

     (A) those warrants (including up to 172,226 shares of Common Stock issuable
upon exercise of such warrants) issued or issuable to Musket Research
Associates, Inc., or other selected dealers, in connection with the sale of the
Series C Securities (as defined below).

                                              BIOFIELD CORP.




                                              By: /s/ D. Carl Long
                                                 ----------------------------
                                                 D. Carl Long
                                                 Chief Executive Officer





<PAGE>   51

                          CERTIFICATE OF AMENDMENT

                                     OF

                         FOURTH AMENDED AND RESTATED

                        CERTIFICATE OF INCORPORATION

                                     OF

                               BIOFIELD CORP.

         Biofield Corp., a Delaware corporation (the "Corporation") does hereby
certify that, in accordance with the provisions of Section 242 of the General
Corporation Law of the State of Delaware, the following amendments to the Fourth
Amended and Restated Certificate of Incorporation of the Corporation were duly
adopted and approved by all of the directors of the Corporation by duly executed
unanimous written consent dated as of December 1, 1995, and by the holders of a
majority of each class of stock of the Corporation entitled to vote thereon by
a majority written consent dated as of December 1, 1995:


<PAGE>   52


     (a) the definition of "Employee Shares" set forth in paragraph 3(b)(iii) of
the Fourth Amended and Restated Certificate of Incorporation shall be amended to
read as follows:

     As used in this Subsection, "Employee Shares" shall mean up to 3,500,000
shares of Common Stock issued or issuable to employees, officers, directors and
consultants of the Corporation pursuant to stock purchase or stock option plans
or arrangements, or both, approved by the Board of Directors;

                                         BIOFIELD CORP.

                                         



                                         By: /s/ Kenneth W. Anstey
                                            ----------------------------
                                            Kenneth W. Anstey
                                            Chief Executive Officer and
                                            President
<PAGE>   53
                           CERTIFICATE OF AMENDMENT
                                      
                                      OF
                                      
                         FOURTH AMENDED AND RESTATED
                                      
                         CERTIFICATE OF INCORPORATION
                                      
                                      OF
                                      
                                BIOFIELD CORP.


         Biofield Corp., a Delaware corporation (the "Corporation") does hereby
certify that, in accordance with the provisions of Section 242 of the General
Corporation Law of the State of Delaware, the following amendments to the
Fourth Amended and Restated Certificate of Incorporation of the Corporation
were duly adopted and approved by all of the directors of the Corporation
at a duly convened meeting held on January 29, 1996 and by the holders of a
majority of each class of stock of the Corporation entitled to vote thereon by
a majority written consent dated as of February 16, 1996:

         Article FOURTH of the Fourth Amended and Restated Certificate of
Incorporation is amended by adding the following new sentence to the end of
Article FOURTH:

         Upon the filing in the office of the Secretary of State of 
<PAGE>   54
Delaware of this Certificate of Amendment to the Fourth Amended and Restated
Certificate of Incorporation of the Corporation, each 2.04 shares of Common
Stock of the Corporation issued and outstanding as of the date of this
amendment shall thereby and thereupon be combined into one share of validly
issued, fully paid, and nonassessable share of Common Stock of the Corporation. 
No scrip or fractional shares will be issued by reason of this amendment.

                                        BIOFIELD CORP.


                                        By: /s/ Kenneth W. Anstey
                                           -------------------------------------
                                             Kenneth W. Anstey
                                             President & CEO