POWER OF ATTORNEY

      Know  all  by  these presents, that the undersigned hereby constitutes and
appoints  David  Gaiero,  Controller  of  OvaScience,  Inc.  (the "Company") and
William  C.  Hicks,  Garrett  M.  Winslow,  Caroline G. Gammill, Anne Leland and
Brenda  Meyette,  each  of  Mintz, Levin, Cohn, Ferris, Glovsky and Popeo, P.C.,
signing  singly,  with  full  power  of substitution, the undersigned's true and
lawful attorney-in-fact to:

      (1)   execute   for   and   on   behalf  of  the  undersigned,  forms  and
            authentication documents for EDGAR Filing Access;

      (2)   do and perform any and all acts for and on behalf of the undersigned
            which may be necessary or desirable to complete and execute any such
            forms and authentication documents;

      (3)   execute  for  and on behalf of the undersigned, in the undersigned's
            capacity  as  an  officer,  director  and/or  10% shareholder of the
            Company,  Forms  3,  4 and 5 in accordance with Section 16(a) of the
            Securities Exchange Act of 1934 and the rules thereunder;

      (4)   do and perform any and all acts for and on behalf of the undersigned
            which may be necessary or desirable to complete and execute any such
            Form  3,  4  or  5  and timely file such form with the United States
            Securities and Exchange Commission and any stock exchange or similar
            authority; and

      (5)   take  any other action of any type whatsoever in connection with the
            foregoing  which, in the opinion of such attorney-in-fact, may be of
            benefit  to,  in  the  best interest of, or legally required by, the
            undersigned, it being understood that the documents executed by such
            attorney-in-fact,  on  behalf  of  the  undersigned pursuant to this
            Power  of  Attorney,  shall  be  in such form and shall contain such
            terms  and  conditions  as such attorney-in-fact may approve in such
            attorney-in-fact's discretion.

      The undersigned hereby grants to each such attorney-in-fact full power and
authority  to  do  and perform any and every act and thing whatsoever requisite,
necessary,  or proper to be done in the exercise of any of the rights and powers
herein granted, as fully to all intents and purposes as the undersigned might or
could  do  if personally present, with full power of substitution or revocation,
hereby  ratifying  and  confirming  all  that  such  attorney-in-fact,  or  such
attorney-in-fact's  substitute  or substitutes, shall lawfully do or cause to be
done  by  virtue  of  this  power  of  attorney and the rights and powers herein
granted.  The  undersigned acknowledges that the foregoing attorneys-in-fact, in
serving in such capacity at the request of the undersigned, is not assuming, nor
is  the  Company  assuming,  any of the undersigned's responsibilities to comply
with Section 16 of the Securities Exchange Act of 1934.

      This  Power  of  Attorney  shall remain in full force and effect until the
undersigned  is  no longer required to file Forms 3, 4 and 5 with respect to the
undersigned's  holdings of and transactions in securities issued by the Company,
unless  earlier  revoked by the undersigned in a signed writing delivered to the
foregoing attorneys-in-fact.

      IN  WITNESS  WHEREOF, the undersigned has caused this Power of Attorney to
be executed this 6 day of September, 2016.

                                                  /s/  Christophe Couturier
                                                  -------------------------
                                                  Christophe Couturier