﻿<?xml version="1.0" encoding="utf-8"?>
<Return xmlns="http://www.irs.gov/efile" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.irs.gov/efile" returnVersion="2009v1.7">
  <ReturnHeader binaryAttachmentCount="0">
    <Timestamp>2011-01-26T12:14:49-06:00</Timestamp>
    <TaxPeriodEndDate>2010-09-30</TaxPeriodEndDate>
    <PreparerFirm>
      <PreparerFirmBusinessName>
        <BusinessNameLine1>Needel Welch &amp; Stone PC</BusinessNameLine1>
      </PreparerFirmBusinessName>
      <PreparerFirmUSAddress>
        <AddressLine1>1001 Hingham Street</AddressLine1>
        <City>Rockland</City>
        <State>MA</State>
        <ZIPCode>02370</ZIPCode>
      </PreparerFirmUSAddress>
    </PreparerFirm>
    <ReturnType>990EZ</ReturnType>
    <TaxPeriodBeginDate>2009-10-01</TaxPeriodBeginDate>
    <Filer>
      <EIN>043469680</EIN>
      <Name>
        <BusinessNameLine1>OBSTETRICAL SOCIETY OF BOSTON INC</BusinessNameLine1>
        <BusinessNameLine2>co Dr Elizabeth Buechler</BusinessNameLine2>
      </Name>
      <NameControl>OBST</NameControl>
      <Phone>7813065304</Phone>
      <USAddress>
        <AddressLine1>26 City Hall Mall</AddressLine1>
        <City>Medford</City>
        <State>MA</State>
        <ZIPCode>02155</ZIPCode>
      </USAddress>
    </Filer>
    <Officer>
      <Name>Elizabeth Buechler</Name>
      <Title>Treasurer</Title>
      <Phone>7813065304</Phone>
      <DateSigned>2010-12-31</DateSigned>
      <AuthorizeThirdParty>1</AuthorizeThirdParty>
    </Officer>
    <Preparer>
      <Name>Timothy Barry</Name>
      <Phone>7819821001</Phone>
      <DatePrepared>2010-12-30</DatePrepared>
    </Preparer>
    <TaxYear>2009</TaxYear>
    <BuildTS>2016-02-24 21:20:13Z</BuildTS>
  </ReturnHeader>
  <ReturnData documentCount="3">
    <IRS990EZ documentId="RetDoc1234200001" referenceDocumentId="RetDoc10045800000">
      <AddressChange>X</AddressChange>
      <MethodOfAccountingCash>X</MethodOfAccountingCash>
      <ScheduleBNotRequired>X</ScheduleBNotRequired>
      <WebSite>n/a</WebSite>
      <Organization501c typeOf501cOrganization="3" referenceDocumentId="RetDoc1039100001">X</Organization501c>
      <GrossReceipts>37603</GrossReceipts>
      <MembershipDues>37575</MembershipDues>
      <InvestmentIncome>28</InvestmentIncome>
      <TotalRevenue>37603</TotalRevenue>
      <SalariesOtherCompEmplBenefits>500</SalariesOtherCompEmplBenefits>
      <OtherExpensesTotal referenceDocumentId="RetDoc2020500001">52530</OtherExpensesTotal>
      <TotalExpenses>53030</TotalExpenses>
      <ExcessOrDeficitForYear>-15427</ExcessOrDeficitForYear>
      <NetAssetsOrFundBalancesBOY>65812</NetAssetsOrFundBalancesBOY>
      <NetAssetsOrFundBalancesEOY>50385</NetAssetsOrFundBalancesEOY>
      <CashSavingsAndInvestments>
        <BOY>65812</BOY>
        <EOY>50385</EOY>
      </CashSavingsAndInvestments>
      <TotalAssets>
        <BOY>65812</BOY>
        <EOY>50385</EOY>
      </TotalAssets>
      <SumOfTotalLiabilities>
        <BOY>0</BOY>
        <EOY>0</EOY>
      </SumOfTotalLiabilities>
      <NetAssetsOrFundBalances>
        <BOY>65812</BOY>
        <EOY>50385</EOY>
      </NetAssetsOrFundBalances>
      <PrimaryExemptPurpose>TO CULTIVATE AND DISSEMINATE SCIENTIFIC KNOWLEDGE IN THE AREAS OF OBSTETRICS, GYNECOLOGY, AND RELATED FIELDS.</PrimaryExemptPurpose>
      <ProgramServiceAccomplishment>
        <DescriptionProgramServiceAccom>Conducted meetings of medical professionals within the fields of gynecology and obstetrics to foster discussions to enhance knowledge and patient treatment.</DescriptionProgramServiceAccom>
        <GrantsAndAllocations>0</GrantsAndAllocations>
        <ProgramServiceExpenses>53030</ProgramServiceExpenses>
      </ProgramServiceAccomplishment>
      <TotalProgramServiceExpenses>53030</TotalProgramServiceExpenses>
      <OfficerDirectorTrusteeKeyEmpl>
        <PersonName>SabRINA CRAIGO MD</PersonName>
        <AddressUS>
          <AddressLine1>750 WASHINGTON ST</AddressLine1>
          <City>BOSTON</City>
          <State>MA</State>
          <ZIPCode>02111</ZIPCode>
        </AddressUS>
        <Title>Past President</Title>
        <AvgHoursPerWkDevotedToPosition>1.00</AvgHoursPerWkDevotedToPosition>
        <Compensation>0</Compensation>
        <ContriToEmplBenefitPlansEtc>0</ContriToEmplBenefitPlansEtc>
        <ExpenseAccountOtherAllowances>0</ExpenseAccountOtherAllowances>
      </OfficerDirectorTrusteeKeyEmpl>
      <OfficerDirectorTrusteeKeyEmpl>
        <PersonName>Laura Bookman MD</PersonName>
        <AddressUS>
          <AddressLine1>330 Brookline Ave</AddressLine1>
          <City>Boston</City>
          <State>MA</State>
          <ZIPCode>02215</ZIPCode>
        </AddressUS>
        <Title>DIRECTOR</Title>
        <AvgHoursPerWkDevotedToPosition>1.00</AvgHoursPerWkDevotedToPosition>
        <Compensation>0</Compensation>
        <ContriToEmplBenefitPlansEtc>0</ContriToEmplBenefitPlansEtc>
        <ExpenseAccountOtherAllowances>0</ExpenseAccountOtherAllowances>
      </OfficerDirectorTrusteeKeyEmpl>
      <OfficerDirectorTrusteeKeyEmpl>
        <PersonName>Ronald Iverson MD</PersonName>
        <AddressUS>
          <AddressLine1>85 East Concord Street</AddressLine1>
          <City>Boston</City>
          <State>MA</State>
          <ZIPCode>02118</ZIPCode>
        </AddressUS>
        <Title>Secretary</Title>
        <AvgHoursPerWkDevotedToPosition>1.00</AvgHoursPerWkDevotedToPosition>
        <Compensation>500</Compensation>
        <ContriToEmplBenefitPlansEtc>0</ContriToEmplBenefitPlansEtc>
        <ExpenseAccountOtherAllowances>0</ExpenseAccountOtherAllowances>
      </OfficerDirectorTrusteeKeyEmpl>
      <OfficerDirectorTrusteeKeyEmpl>
        <PersonName>Susan Haas MD</PersonName>
        <AddressUS>
          <AddressLine1>133 Brookline Ave</AddressLine1>
          <City>Boston</City>
          <State>MA</State>
          <ZIPCode>02215</ZIPCode>
        </AddressUS>
        <Title>President</Title>
        <AvgHoursPerWkDevotedToPosition>2.00</AvgHoursPerWkDevotedToPosition>
        <Compensation>0</Compensation>
        <ContriToEmplBenefitPlansEtc>0</ContriToEmplBenefitPlansEtc>
        <ExpenseAccountOtherAllowances>0</ExpenseAccountOtherAllowances>
      </OfficerDirectorTrusteeKeyEmpl>
      <OfficerDirectorTrusteeKeyEmpl>
        <PersonName>Jeffrey Ecker MD</PersonName>
        <AddressUS>
          <AddressLine1>55 Fruit Street</AddressLine1>
          <City>Boston</City>
          <State>MA</State>
          <ZIPCode>02114</ZIPCode>
        </AddressUS>
        <Title>1st VP</Title>
        <AvgHoursPerWkDevotedToPosition>1.00</AvgHoursPerWkDevotedToPosition>
        <Compensation>0</Compensation>
        <ContriToEmplBenefitPlansEtc>0</ContriToEmplBenefitPlansEtc>
        <ExpenseAccountOtherAllowances>0</ExpenseAccountOtherAllowances>
      </OfficerDirectorTrusteeKeyEmpl>
      <OfficerDirectorTrusteeKeyEmpl>
        <PersonName>Elizabeth Buechler MD</PersonName>
        <AddressUS>
          <AddressLine1>26 City Hall Mall</AddressLine1>
          <City>Medford</City>
          <State>MA</State>
          <ZIPCode>02155</ZIPCode>
        </AddressUS>
        <Title>Treasurer</Title>
        <AvgHoursPerWkDevotedToPosition>3.00</AvgHoursPerWkDevotedToPosition>
        <Compensation>0</Compensation>
        <ContriToEmplBenefitPlansEtc>0</ContriToEmplBenefitPlansEtc>
        <ExpenseAccountOtherAllowances>0</ExpenseAccountOtherAllowances>
      </OfficerDirectorTrusteeKeyEmpl>
      <OfficerDirectorTrusteeKeyEmpl>
        <PersonName>Aviva Lee-Parritz MD</PersonName>
        <AddressUS>
          <AddressLine1>85 East Concord Street</AddressLine1>
          <City>BostON</City>
          <State>MA</State>
          <ZIPCode>02118</ZIPCode>
        </AddressUS>
        <Title>2nd VP</Title>
        <AvgHoursPerWkDevotedToPosition>1.00</AvgHoursPerWkDevotedToPosition>
        <Compensation>0</Compensation>
        <ContriToEmplBenefitPlansEtc>0</ContriToEmplBenefitPlansEtc>
        <ExpenseAccountOtherAllowances>0</ExpenseAccountOtherAllowances>
      </OfficerDirectorTrusteeKeyEmpl>
      <OfficerDirectorTrusteeKeyEmpl>
        <PersonName>Annie Liau MD</PersonName>
        <AddressUS>
          <AddressLine1>77 Massachusetts Ave</AddressLine1>
          <City>Cambridge</City>
          <State>MA</State>
          <ZIPCode>02139</ZIPCode>
        </AddressUS>
        <Title>DIRECTOR</Title>
        <AvgHoursPerWkDevotedToPosition>1.00</AvgHoursPerWkDevotedToPosition>
        <Compensation>0</Compensation>
        <ContriToEmplBenefitPlansEtc>0</ContriToEmplBenefitPlansEtc>
        <ExpenseAccountOtherAllowances>0</ExpenseAccountOtherAllowances>
      </OfficerDirectorTrusteeKeyEmpl>
      <OfficerDirectorTrusteeKeyEmpl>
        <PersonName>Charles Kawada MD</PersonName>
        <AddressUS>
          <AddressLine1>330 Mount Auburn St</AddressLine1>
          <City>Cambridge</City>
          <State>MA</State>
          <ZIPCode>02138</ZIPCode>
        </AddressUS>
        <Title>Immediate Past Pres</Title>
        <AvgHoursPerWkDevotedToPosition>1.00</AvgHoursPerWkDevotedToPosition>
        <Compensation>0</Compensation>
        <ContriToEmplBenefitPlansEtc>0</ContriToEmplBenefitPlansEtc>
        <ExpenseAccountOtherAllowances>0</ExpenseAccountOtherAllowances>
      </OfficerDirectorTrusteeKeyEmpl>
      <ActivitiesNotPreviouslyRpt>0</ActivitiesNotPreviouslyRpt>
      <MadeChangesToOrgnzngEtcDoc>0</MadeChangesToOrgnzngEtcDoc>
      <OrganizationHadUBI>0</OrganizationHadUBI>
      <OrganizationDissolvedEtc>0</OrganizationDissolvedEtc>
      <DirectIndirectPoliticalExpend>0</DirectIndirectPoliticalExpend>
      <MadeLoansToFromOfficers>0</MadeLoansToFromOfficers>
      <TaxImposedUnderIRC4911>0</TaxImposedUnderIRC4911>
      <TaxImposedUnderIRC4912>0</TaxImposedUnderIRC4912>
      <TaxImposedUnderIRC4955>0</TaxImposedUnderIRC4955>
      <EngagedInExcessBenefitTrans>0</EngagedInExcessBenefitTrans>
      <AmountOfTaxImposedOnOrgMgr>0</AmountOfTaxImposedOnOrgMgr>
      <AmountOfTaxReimbursedByOrg>0</AmountOfTaxReimbursedByOrg>
      <ProhibitedTaxShelterTrans>0</ProhibitedTaxShelterTrans>
      <StatesWhereCopyOfReturnIsFiled>MA</StatesWhereCopyOfReturnIsFiled>
      <TheBooksAreInCareOf>
        <NamePerson>ELIZABETH BUECHLER MD</NamePerson>
        <AddressUS>
          <AddressLine1>26 City Hall Mall</AddressLine1>
          <City>Medford</City>
          <State>MA</State>
          <ZIPCode>02155</ZIPCode>
        </AddressUS>
        <TelephoneNumber>7813065304</TelephoneNumber>
      </TheBooksAreInCareOf>
      <ForeignFinancialAccount>0</ForeignFinancialAccount>
      <ForeignOffice>0</ForeignOffice>
      <MaintainAnyDonorAdvisedFunds>0</MaintainAnyDonorAdvisedFunds>
      <RelatedOrgControlledEntity>0</RelatedOrgControlledEntity>
      <EngagePoliticalCmpgnActivities>0</EngagePoliticalCmpgnActivities>
      <EngageInLobbyingActivities>0</EngageInLobbyingActivities>
      <OperatingSchool>0</OperatingSchool>
      <TrnsfrsExemptNonCharRelatedOrg>0</TrnsfrsExemptNonCharRelatedOrg>
      <PartVIOfCompOfHighestPaidEmpl>NONE</PartVIOfCompOfHighestPaidEmpl>
      <PartVIAHghstPaidCntrctProfSer>NONE</PartVIAHghstPaidCntrctProfSer>
    </IRS990EZ>
    <IRS990ScheduleA documentId="RetDoc1039100001">
      <PubliclySupportedOrg509a2>X</PubliclySupportedOrg509a2>
      <GiftsGrantsContribReceived509>
        <CurrentTaxYearMinus4Years>47210</CurrentTaxYearMinus4Years>
        <CurrentTaxYearMinus3Years>40810</CurrentTaxYearMinus3Years>
        <CurrentTaxYearMinus2Years>42554</CurrentTaxYearMinus2Years>
        <CurrentTaxYearMinus1Year>34450</CurrentTaxYearMinus1Year>
        <CurrentTaxYear>37575</CurrentTaxYear>
        <Total>202599</Total>
      </GiftsGrantsContribReceived509>
      <Total509>
        <CurrentTaxYearMinus4Years>47210</CurrentTaxYearMinus4Years>
        <CurrentTaxYearMinus3Years>40810</CurrentTaxYearMinus3Years>
        <CurrentTaxYearMinus2Years>42554</CurrentTaxYearMinus2Years>
        <CurrentTaxYearMinus1Year>34450</CurrentTaxYearMinus1Year>
        <CurrentTaxYear>37575</CurrentTaxYear>
        <Total>202599</Total>
      </Total509>
      <AmtsRecdFromDisqualPersons>
        <Total>0</Total>
      </AmtsRecdFromDisqualPersons>
      <AmtsFromSubstContributors>
        <Total>0</Total>
      </AmtsFromSubstContributors>
      <SupportFromDQPsEtc>
        <Total>0</Total>
      </SupportFromDQPsEtc>
      <PublicSupportTotal509>202599</PublicSupportTotal509>
      <GrossInvestmentIncome509>
        <CurrentTaxYearMinus4Years>250</CurrentTaxYearMinus4Years>
        <CurrentTaxYearMinus3Years>238</CurrentTaxYearMinus3Years>
        <CurrentTaxYearMinus2Years>180</CurrentTaxYearMinus2Years>
        <CurrentTaxYearMinus1Year>122</CurrentTaxYearMinus1Year>
        <CurrentTaxYear>28</CurrentTaxYear>
        <Total>818</Total>
      </GrossInvestmentIncome509>
      <InvestmentIncomeAndUBTI>
        <CurrentTaxYearMinus4Years>250</CurrentTaxYearMinus4Years>
        <CurrentTaxYearMinus3Years>238</CurrentTaxYearMinus3Years>
        <CurrentTaxYearMinus2Years>180</CurrentTaxYearMinus2Years>
        <CurrentTaxYearMinus1Year>122</CurrentTaxYearMinus1Year>
        <CurrentTaxYear>28</CurrentTaxYear>
        <Total>818</Total>
      </InvestmentIncomeAndUBTI>
      <TotalSupportTotal>
        <CurrentTaxYearMinus4Years>47460</CurrentTaxYearMinus4Years>
        <CurrentTaxYearMinus3Years>41048</CurrentTaxYearMinus3Years>
        <CurrentTaxYearMinus2Years>42734</CurrentTaxYearMinus2Years>
        <CurrentTaxYearMinus1Year>34572</CurrentTaxYearMinus1Year>
        <CurrentTaxYear>37603</CurrentTaxYear>
        <Total>203417</Total>
      </TotalSupportTotal>
      <PublicSupportPercentage509>0.99600</PublicSupportPercentage509>
      <PriorYearSupportPercentage>0.99540</PriorYearSupportPercentage>
      <InvestmentIncomePercentage>0.00400</InvestmentIncomePercentage>
      <PriorYrInvestIncomePercentage>0.00460</PriorYrInvestIncomePercentage>
      <ThirtyThreePercntTestsCY509>X</ThirtyThreePercntTestsCY509>
    </IRS990ScheduleA>
    <TransferPrsnlBnftContractsDecl documentId="RetDoc10045800000">
      <Declaration>The organization did not, during the year, receive any funds, directly,or indirectly, to pay premiums on a personal benefit contract.The organization, did not, during the year, pay any premiums, directly,or indirectly, on a personal benefit contract.</Declaration>
    </TransferPrsnlBnftContractsDecl>
  </ReturnData>
</Return>