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 May, 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
---------------------



                 SERONO RECEIVES FDA APPROVAL FOR GONAL-F(R) PEN
                              TO TREAT INFERTILITY

   FIRST AND ONLY PREFILLED DEVICE WITH NEW LIQUID FORMULATION DEVELOPED TO MAKE
                    INFERTILITY TREATMENT EASIER FOR PATIENTS



GENEVA,  SWITZERLAND  AND  ROCKLAND,  MA,  MAY  27,  2004 - Serono, Inc., the US
affiliate of Serono (virt-x: SEO and NYSE: SRA), announced today that the United
States  Food  and Drug Administration (FDA) has approved a prefilled device that
delivers  a  new  liquid  formulation of the most prescribed gonadotropin in the
world:  Gonal-f(R)  RFF  Pen  (follitropin  alfa  injection).

Gonal-f(R)  RFF  Pen is the first and only prefilled and ready-to-use multi-dose
FSH  (follicle  stimulating  hormone)  in the US.  It will be available in three
sizes  that  deliver  either  300  IU,  450  IU  or  900 IU of liquid Gonal-f(R)
filled-by-mass,  which can be administered in multiple doses.  Developed to make
infertility  treatment easier, it provides patients with a new way to administer
Gonal-f(R) by simply dialing the correct dose without the need to mix medication
or  load  cartridges.  It  was  designed  specifically  for  the  treatment  of
infertility  to  allow patients to easily and accurately deliver a precise daily
dose  of  medication.

"We are proud to be the first company to offer a prefilled and ready-to-use pen,
providing a new option for infertility patients that is easy and simple to use,"
said  Bharat Tewarie, MD, Executive Vice President, Reproductive Health, Serono,
Inc.  "Serono  is  the  world  leader  in  reproductive health, and we are again
demonstrating  our  commitment  to  continually  improve the patient experience.
Gonal-f(R)  RFF  Pen,  in  addition  to  our  multi-dose  and  single-dose  vial
presentations, gives us the most extensive and complete portfolio of infertility
products to allow for enhanced dosing flexibility and individualized treatment."
Serono  expects Gonal-f(R) RFF Pen to be available in the US in Q3 of this year.



RFF stands for revised formulation female, the new Gonal-f(R) presentations
approved by the FDA.



Gonal-f(R)  RFF  Pen  is  indicated  for induction of ovulation and pregnancy in
anovuluatory  infertile women in whom the cause of infertility is functional and
not due to primary ovarian failure.  It is also indicated for the development of
multiple  follicles in ovulatory women participating in an Assisted Reproductive
Technology  (ART)  program.

Gonal-f(R)  is  a  highly  consistent, filled-by-mass recombinant human follicle
stimulating  hormone  (r-hFSH)  prescribed  to  supplement  or replace naturally
occurring  FSH,  which  stimulates  the development of follicles in the ovaries.
The Gonal-f(R) prefilled pen was previously approved by the European Commission,
the  Swiss  and  the  Australian  Regulatory Authorities and launch is underway.

Infertility  is  defined as the inability to achieve pregnancy after one year of
regular,  unprotected  intercourse  (six  months  if  the woman is over 35).  It
affects  about  6.1  million  Americans,  which  represents  about 10 percent of
couples  in  their  childbearing  years.  About  70% of patients who are treated
succeed  in  having  children.


ADDITIONAL  INFORMATION
Side  effects  may occur with the use of infertility medications and, therefore,
they  should  only  be prescribed by physicians who are thoroughly familiar with
infertility  problems  and  their management.  Ovarian hyperstimulation syndrome
(OHSS)  with or without vascular and pulmonary complications, can occur with the
use  of infertility drugs.  Reports of multiple births have been associated with
gonadotropin  treatment.  Side  effects  in  women  using Gonal-f(R) RFF Pen for
infertility  treatment  may include headache, stomach pain, bloating, nausea and
injection  site  bruising.


ABOUT SERONO, INC. AND INFERTILITY
Serono,  Inc. is dedicated to providing patient-friendly, innovative products to
help  couples  build families.  It is the only company to offer a full portfolio
of  infertility  medications  for  every  stage  of  the  reproductive cycle and
recombinant versions of two hormones needed to treat infertility.



                                                                             2/3

ABOUT  SERONO
Serono,  Inc.,  located in Rockland, MA, is the US affiliate of Serono, a global
biotechnology  leader,  headquartered  in  Geneva, Switzerland. Serono has seven
recombinant  products,  Rebif(R)  (interferon  beta-1a), Gonal-f(R) (follitropin
alfa  for  injection),  Luveris(R)  (lutropin  alfa),  Ovidrel  PreFilled
Syringe(R)/Ovitrelle(R)  (choriogonadotropin  alfa  injection),  Serostim(R)
[somatropin  (rDNA  origin)  for injection], Saizen(R) [somatropin (rDNA origin)
for  injection]  and  Zorbtive(TM)  [somatropin  (rDNA  origin)  for injection].
(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. Serono's research programs are focused on growing these
businesses  and  on  establishing  new  therapeutic  areas. Currently, there are
approximately  30  ongoing  development  projects.

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 March 25, 2004.  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, INC., ROCKLAND, MA
MEDIA RELATIONS:                  INVESTOR RELATIONS:
Tel.  +1 781 681 2443             Tel.  +1 781 681 2552
Fax:  +1 781 681 2935             Fax:  +1 781 681 2912
http://www.seronousa.com
------------------------

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:  SEO.VX / SRA.N
---------------------             Bloomberg:  SEO VX / SRA US



------------------
*  Package  inserts  for  Serono's  US  marketed  products  are  available  at
www.seronousa.com  or  by  calling  1-888-275-7376.
-----------------



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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)



May 27, 2004                             By:   /s/ Francois Naef
                                               --------------------------
                                               Name:  Francois Naef
                                               Title: Secretary