SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549
                                    ________

                                    FORM 6-K

                        REPORT OF FOREIGN PRIVATE ISSUER
                      PURSUANT TO RULE 13a-16 OR 15d-16 OF
                       THE SECURITIES EXCHANGE ACT OF 1934

                         For the month of February, 2004

                                  Serono S.A.
                      -----------------------------------
                              (Registrant's Name)

                            15 bis, Chemin des Mines
                                Case Postale 54
                                CH-1211 Geneva 20
                                  Switzerland
                          -------------------------------
                    (Address of Principal Executive Offices)

                                    1-15096
                      -----------------------------------
                              (Commission File No.)

     (Indicate  by  check  mark whether the registrant files or will file annual
reports under cover of Form 20-F or Form 40-F.)

     Form  20-F  X Form  40-F
                ---           ---

     (Indicate  by  check  mark  if the registrant is submitting the Form 6-K in
paper as permitted by Regulation S-T Rule 101 (b)(1).) ______

     (Indicate  by  check  mark  if the registrant is submitting the Form 6-K in
paper as permitted by Regulation S-T Rule 101 (b)(7).) ______

     (Indicate  by  check  mark  whether  the  registrant  by  furnishing  the
information contained in this form is also thereby furnishing the information to
the  Commission  pursuant to Rule 12g3-2(b) under the Securities Exchange Act of
1934.)

     Yes     No  X
         ---    ---

     (If  "Yes"  is  marked,  indicate  below  the  file  number assigned to the
registrant in connection with Rule 12g3-2(b): 82-______)



                                                                          SERONO


Media Release


FOR  IMMEDIATE  RELEASE
-----------------------


             EUROPEAN COMMISSION APPROVES GONAL-F(R) FILLED-BY-MASS
                                  PREFILLED PEN

           THE MOST CONSISTENT FSH IS NOW AVAILABLE IN AN ACCURATE AND
                           EASY-TO-USE PRE-FILLED PEN

GENEVA,  SWITZERLAND  -  FEBRUARY 25, 2004 - Serono  (virt-x: SEO and NYSE: SRA)
announced  today  that  the  European  Commission  has approved  its  GONAL-f(R)
Filled-by-Mass  solution  for  injection in a pre-filled pen, which delivers the
company's  market-leading  recombinant  human  follicle-stimulating  hormone.

"As  the  worldwide  leader  in  infertility  treatment,  Serono is committed to
developing  innovative  products,"  said  Ernesto  Bertarelli,  Chief  Executive
Officer  of  Serono.  "The  GONAL-f(R)(FbM)  Prefilled  Pen  delivers  the  most
consistent FSH in the only ready-to-use pre-filled pen available on the market."

To  make  infertility  treatment  easier and more accurate for patients, the new
GONAL-f(R)  (FbM)  Prefilled  Pen  is  specifically  designed  for  infertility
treatment  and will be available in 3 multidose presentations; 300 IU/0.5 ml (22
mcg/0.5 ml), 450 IU/0.75 ml (33 mcg/0.75 ml) and 900 IU/1.5 ml (66 mcg/1.5 ml).

"This  is  the first ready-to-use pen that enables us to combine the efficacy of
the  most  consistent  FSH  with  the flexibility to individualize the dosing in
ovulation induction and Assisted Reproductive Techniques for each patient," said
Professor Christoph Keck, M.D., from the Department of Obstetrics and Gynecology
of  the  University  of  Freiburg,  Germany.  "Having  GONAL-f(R)  (FbM)  in  a
pre-filled,  ready-to-use  pen  will  make  the  administration  easier  for the
patients,  and  help  them  to  ensure  that they have injected the right dose."


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The  GONAL-f(R)  (FbM) Prefilled Pen will continue to carry the same indications
as  the  currently  marketed  product  for a) anovulation in women who have been
unresponsive  to  treatment  with  clomiphene  citrate,  b)  stimulation  of
multifollicular  development  in patients undergoing superovulation for assisted
reproductive  technologies,  c)  in  association with a luteinising hormone (LH)
preparation  for  the stimulation of follicular development in women with severe
LH  and FSH deficiency and d) for stimulation of spermatogenesis in men who have
congenital  or  acquired  hypogonadotrophic  hypogonadism.

Serono  expects  the  GONAL-f(R)(FbM)  Prefilled  Pen to be introduced in Europe
during  the  first  half  of  this  year.


ADDITIONAL PRODUCT INFORMATION
------------------------------

GONAL-f(R)  Filled-by-Mass  (follitropin  alpha)  is  a  recombinant  human
follicle-stimulating  hormone,  which  is  equivalent  in  its  structure to the
naturally  occurring  human FSH in the body. GONAL-f(R)(FbM) is used in clinical
practice  to  treat  infertile  women  and  men  with  low  or lacking naturally
occurring  FSH.  It  is  the  world's  leading  treatment  for  male  and female
infertility  and  is  registered  in  more  than  80 countries around the world.
Infertility  is  defined as the inability of a couple to achieve pregnancy after
one  year  of  regular, unprotected intercourse (six months if the woman is over
35).  It  affects  about  10 million Europeans, representing about 10 percent of
couples in their childbearing years. Infertility is just as likely to be related
to  male  factors  as  female  factors,  which each account for about a third of
infertility  problems.  The remaining third are either a combination of male and
female  factors  or  are  unexplained.

SERONO AND INFERTILITY TREATMENT
--------------------------------

Serono,  the  world  leader  in  reproductive  health, is dedicated to providing
patient-friendly,  innovative products to help couples build families. Serono is
the only company to offer a full portfolio of fertility drugs for every stage of
the  reproductive cycle and recombinant versions of the three hormones needed to
treat  infertility:  GONAL-f(R) FbM (follitropin alfa), to stimulate the ovaries
and  produce  eggs;  Luveris(R)  (lutropin  alfa),  to  stimulate  follicular
development  in  women who are profoundly LH deficient; Cetrotide(R) (cetrorelix
acetate)  to  prevent  a  premature  ovulation; Ovitrelle(R) (choriogonadotropin
alfa),  to  help follicles mature and release eggs; and Crinone(R) (progesterone
gel),  to  help  establish  and  maintain  a  pregnancy.

For  more  information  on  infertility visit www.fertility.com and for Serono's
                                              -----------------
marketed  fertility  products  visit  www.serono.com (1).
                                      --------------




________________________
(1)  These  websites  are  not  intended  for  US residents. US residents should
consult  the  Serono  Inc.  fertility  website  at  www.seronofertility.com  or
                                                    -----------------------
www.seronousa.com.
-----------------


                                                                             2/3

ABOUT SERONO

Serono  is  a  global  biotechnology  leader.  The Company has seven recombinant
products,  Rebif(R),  Gonal-f(R),  Luveris(R),  Ovidrel(R)/Ovitrelle(R),
Serostim(R),  Saizen(R) and Zorbtive (Luveris(R) is not approved in the USA). In
addition  to  being  the  world leader in reproductive health, Serono has strong
market  positions  in  neurology,  metabolism and growth. The Company's research
programs  are  focused  on  growing  these  businesses  and  on establishing new
therapeutic areas. Currently, there are over 30 projects in development.

In  2003,  Serono  achieved worldwide revenues of US$ 2,018.6 million, and a net
income  of  US$390.0 million, making it the third largest biotech company in the
world. Its products are sold in over 90 countries. Bearer shares of Serono S.A.,
the  holding company, are traded on the virt-x (SEO) and its American Depositary
Shares  are  traded  on  the  New  York  Stock  Exchange  (SRA).



                                       ###

Some  of  the  statements  in  this  press  release  are  forward  looking. Such
statements  are inherently subject to known and unknown risks, uncertainties and
other  factors  that  may  cause  actual results, performance or achievements of
Serono  S.A.  and  affiliates  to be materially different from those expected or
anticipated  in  the  forward-looking statements. Forward-looking statements are
based on Serono's current expectations and assumptions, which may be affected by
a  number  of  factors, including those discussed in this press release and more
fully  described  in  Serono's  Annual  Report  on Form 20-F filed with the U.S.
Securities and Exchange Commission on April 17, 2003.  These factors include any
failure  or  delay  in  Serono's ability to develop new products, any failure to
receive  anticipated  regulatory  approvals,  any  problems  in  commercializing
current  products  as  a  result of competition or other factors, our ability to
obtain  reimbursement  coverage  for  our  products,  and government regulations
limiting  our  ability  to  sell  our  products. Serono has no responsibility to
update the forward-looking statements contained in this press release to reflect
events or circumstances occurring after the date of this press release.

                                       ###



FOR MORE INFORMATION, PLEASE CONTACT:

SERONO IN GENEVA, SWITZERLAND:
MEDIA  RELATIONS:                 INVESTOR  RELATIONS:
Tel:  +41-22-739 36 00            Tel:  +41-22-739 36 01
Fax:  +41-22-739 30 85            Fax:  +41-22-739 30 22
http://www.serono.com             Reuters:  SEOZ.VX / SRA.N
---------------------             Bloomberg:  SEO VX / SRA US

SERONO, INC., ROCKLAND, MA,
USA:
                                  INVESTOR  RELATIONS:
                                  Tel.  +1 781 681 2552
                                  Fax:  +1 781 681 2912


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                                   SIGNATURES

     Pursuant  to  the  requirements of the Securities Exchange Act of 1934, the
registrant  has  duly  caused  this  report  to  be  signed on its behalf by the
undersigned,  thereunto  duly  authorized.



                                         SERONO S.A.
                                         a Swiss corporation
                                         (Registrant)



February 25, 2004                        By:   /s/ Allan Shaw
                                               ---------------------------
                                         Name:   Allan Shaw
                                         Title:  Chief Financial Officer