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                                                                      EXHIBIT 12
AETNA INC.

COMPUTATION OF RATIO OF EARNINGS TO FIXED CHARGES AND RATIO OF EARNINGS TO
COMBINED FIXED CHARGES AND PREFERRED STOCK DIVIDENDS

<TABLE>
<CAPTION>
                                          Three Months Ended                              Years Ended
                                               March 31,                                  December 31,
                                          -------------------   -------------------------------------------------------------
(Millions)                                         1998              1997         1996         1995         1994         1993
-----------------------------------------------------------------------------------------------------------------------------
<S>                                              <C>            <C>             <C>          <C>          <C>       <C>
Pretax income (loss) from                                                                              
 continuing operations                           $279.2          $1,511.2       $338.7       $726.2       $627.5    $(1,014.7)
                                                                                                       
Add back fixed charges                             85.0             321.9        245.1        187.0        170.8        154.7
Minority interest                                  (4.9)             14.7         16.4         16.1         11.4          7.0
-----------------------------------------------------------------------------------------------------------------------------
   Income (loss) as adjusted                     $359.3          $1,847.8       $600.2       $929.3       $809.7    $  (853.0)
=============================================================================================================================
Fixed charges:                                                                                         
  Interest on indebtedness (1)                   $ 56.9          $  235.8       $168.3       $115.9       $ 98.6         77.4
  Portion of rents representative                                                                      
   of interest factor                              28.1              86.1         76.8         71.1         72.2         77.3
-----------------------------------------------------------------------------------------------------------------------------
   Total fixed charges                           $ 85.0          $  321.9       $245.1       $187.0       $170.8    $   154.7
=============================================================================================================================
Preferred stock dividend                                                                               
 requirements                                      23.2              92.4         41.1           --           --           --
-----------------------------------------------------------------------------------------------------------------------------
Total combined fixed charges                                                                           
 and preferred stock dividend                                                                          
 requirements                                    $108.2          $  414.3       $286.2       $187.0       $170.8    $   154.7
=============================================================================================================================
Ratio of earnings to fixed                                                                             
 charges                                           4.23              5.74         2.45         4.97         4.74        (5.51)
=============================================================================================================================
Ratio of earnings to combined                                                                          
 fixed charges and preferred                                                                           
 stock dividends                                   3.32              4.46         2.10         4.97         4.74        (5.51)
=============================================================================================================================
</TABLE>

(1) For the three months ended March 31, 1998 and years ended December 31, 1997,
    1996, 1995 and 1994, interest on indebtedness includes the dividends paid to
    preferred shareholders of a subsidiary. (See Note 14 of Notes to Financial
    Statements in the Company's 1997 Annual Report.)


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                                                          Exhibit 12 (Continued)
AETNA SERVICES, INC. (1)

COMPUTATION OF RATIO OF EARNINGS TO FIXED CHARGES AND RATIO OF EARNINGS TO
COMBINED FIXED CHARGES AND PREFERRED STOCK DIVIDENDS


<TABLE>
<CAPTION>
                                                                   Three Months Ended              Years Ended
                                                                        March 31,                  December 31,
                                                                   ------------------      --------------------------
(Millions)                                                                   1998               1997             1996
---------------------------------------------------------------------------------------------------------------------
<S>                                                                        <C>              <C>                <C>
Pretax income from continuing
 operations                                                                $237.3           $1,505.2           $335.0

Add back fixed charges                                                       84.0              318.1            243.8
Minority interest                                                            (4.7)              15.7             16.4
---------------------------------------------------------------------------------------------------------------------
   Income as adjusted                                                      $316.6           $1,839.0           $595.2
=====================================================================================================================
Fixed charges:
  Interest on indebtedness (2)                                             $ 56.9           $  234.0           $168.3
  Portion of rents representative
   of interest factor                                                        27.1               84.1             75.5
---------------------------------------------------------------------------------------------------------------------
   Total fixed charges                                                     $ 84.0           $  318.1           $243.8
=====================================================================================================================
Preferred stock dividend
 requirements                                                                  --                 --               --
---------------------------------------------------------------------------------------------------------------------
Total combined fixed charges
 and preferred stock dividend
 requirements                                                              $ 84.0           $  318.1           $243.8
=====================================================================================================================
Ratio of earnings to fixed
 charges                                                                     3.77               5.78             2.44
=====================================================================================================================
Ratio of earnings to combined
 fixed charges and preferred
 stock dividends                                                             3.77               5.78             2.44
=====================================================================================================================
</TABLE>

(1) Aetna Inc. has fully and unconditionally guaranteed the payment of all
    principal, premium, if any, and interest on all outstanding debt securities
    of Aetna Services, Inc. (See Note 13 of Notes to Financial Statements in the
    Company's 1997 Annual Report.)

(2) Includes the dividends paid to preferred shareholders of a subsidiary.(See
    Note 14 of Notes to Financial Statements in the Company's 1997 Annual
    Report.)


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