SecProbe.io

Mail Stop 4720

March 8, 2016

Michelle Dipp , M.D., PH.D.
Chief Executive Officer and Executive Chairman
OvaScience, Inc.
9 Fourth Avenue
Waltham, M A 02451

Re: OvaScience, Inc.
  Registration Statement on Form S-3
Filed  February 26, 2016
  File No.  333-209778

Dear Dr. Dipp :

We have limited our review of your registration statement to those issues w e have
addressed in our comment .  In some of our comments, we may ask you to provide us with
information so we may better understand your disclosure.

Please respond to this letter by amending your registration statement and providing the
requested information .  If you do not believe our com ment appl ies to your facts and
circumstances or do not believe an amendment is appropriate, please tell us why in your
response.

After reviewing any amendment to your registration statement and the information you
provide in response to the comment , we may have  additional comments.

General

1. We note that you incorporate by reference your Annual Report on Form 10 -K for the year
ended December 31, 2015.  However, the Form 10 -K incorporates by reference
information from your definitive proxy statement that has not been filed  yet.  Please note
that we will not be in a position to take your filing effective until you have amended the
Form 10 -K to include Part III information or filed the definitive proxy statement.  Please
refer to Compliance and Disclosu re Interpretations, Securities Act Forms, Question
123.01 and Regulation S -K, Question 117.05 for guidance.

We urge all persons who are responsible for the accuracy and adequacy of the disclosure
in the filing to be certain that the filing includes the information the Securities Act of 193 3 and
all applicable Securities  Act rules require.   Since the company and its management are in

Dr. Michelle  Dipp
OvaScience, Inc.
March 8, 2016
Page 2

 possession of all facts relating to a company’s disclosure, they are responsible for the accuracy
and adequacy of the disclos ures they have made.

Notwithstanding our comment , in the event you request acceleration of the effective date
of the pending registration statement , please provide a written statement from the company
acknowledging that:

 should the Commission or the staff, acting pursuant to delegated authority, declare the
filing effective, it does not foreclose the Commission from taking any action with respect
to the filing;

 the action of the Commission or the staff, acting pursuant t o delegated authority, in
declaring the filing effective, does not relieve the company from its full responsibility for
the adequacy and accuracy of the disclosure in the filing; and

 the company may not assert staff comments and the declaration of effect iveness as a
defense in any proceeding initiated by the Commission or any person under the federal
securities laws of the United States.

Please refer to Rules 460 and 461 regarding requests for  acceleration .  We will consider a
written request for acceler ation of the effective date of the registration statement as confirmation
of the fact that those requesting acceleration are aware of their respective responsibilities under
the Securities Act of 1933 and the Securities Exchange Act of 1934 as they relate to the proposed
public offering of the securities specified in the above registration statement.  Please allow
adequate time  for us to review any amendment prior to the requested effective date of the
registration statement.

Please contact  Dorrie Yal e at 202-551-8776  or Joseph McCann at 202 -551-6262 with any
questions.

Sincerely,

 /s/ Joseph McCann for

 Suzanne Hayes
Assistant Director
Office of Healthcare and Insurance

cc: William C. Hicks , Esq.
      Mintz, Levin, Cohn, Ferris, Glovsky and Popeo, P.C.