<SEC-DOCUMENT>0001104659-13-069573.txt : 20130912
<SEC-HEADER>0001104659-13-069573.hdr.sgml : 20130912
<ACCEPTANCE-DATETIME>20130912172644
ACCESSION NUMBER:		0001104659-13-069573
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20130911
FILED AS OF DATE:		20130912
DATE AS OF CHANGE:		20130912

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			OvaScience, Inc.
		CENTRAL INDEX KEY:			0001544227
		STANDARD INDUSTRIAL CLASSIFICATION:	PHARMACEUTICAL PREPARATIONS [2834]
		IRS NUMBER:				451472564
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		215 FIRST STREET
		STREET 2:		SUITE 240
		CITY:			CAMBRIDGE
		STATE:			MA
		ZIP:			02142
		BUSINESS PHONE:		617-500-2802

	MAIL ADDRESS:	
		STREET 1:		215 FIRST STREET
		STREET 2:		SUITE 240
		CITY:			CAMBRIDGE
		STATE:			MA
		ZIP:			02142

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			BLECK CHRISTOPHER A
		CENTRAL INDEX KEY:			0001187407

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-35890
		FILM NUMBER:		131094824
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>a4.xml
<DESCRIPTION>4
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0306</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2013-09-11</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001544227</issuerCik>
        <issuerName>OvaScience, Inc.</issuerName>
        <issuerTradingSymbol>OVAS</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001187407</rptOwnerCik>
            <rptOwnerName>BLECK CHRISTOPHER A</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O OVASCIENCE, INC.,</rptOwnerStreet1>
            <rptOwnerStreet2>215 FIRST STREET, SUITE 240</rptOwnerStreet2>
            <rptOwnerCity>CAMBRIDGE</rptOwnerCity>
            <rptOwnerState>MA</rptOwnerState>
            <rptOwnerZipCode>02142</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>Chief Commercial Officer</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2013-09-11</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>P</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>2000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>11.15</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>2000</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>By Christopher Bleck Revocable Trust dated July 30, 2009</value>
                    <footnoteId id="F1"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">The trustees of the Christopher Bleck Revocable Trust dated July 30, 2009 are the reporting person and his spouse. They jointly exercise voting and investment power over the shares of record held by the trust.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>/s/ Christopher Bleck</signatureName>
        <signatureDate>2013-09-12</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
