FetalMembranesandPlacenta1.Fetalmembranes-chorion,amnion,yolksac,allantois,umbilicalcord(1)Chorion1)FormationSyncytiotrophoblast+Cytotrophoblast+Extra-embryonicMesoderm-Villus2)DevelopmentofVillus PrimaryVilliSecondaryVilliTertiaryVilli,FreeVillitoformOuterCytotrophoblastShell3)ClassificationChorionFrondosumadjacenttoDeciduaBasalis.Villi,suppliedwith bloodfromspiralarterybecomecompactandgrowwell,andfinallytoformfetalsideofplacenta. . ChorionLaeve adjacenttoDeciduaCapsularis.Villi, devoid of blood from spiral artery becomestretchedanddegenerate.4)AbnormalDevelopmentHydatidiformMoleVillishowgrape-shapedorblister-likestructures,finallyleadingembryotodeath.ChoriocarcinomaTrophoblastcellsbecomemalignanthyperplasia. 2.Amnion 1) Translucentthinmembrane=amnioticcells(inner)+extra-embryonicmesoderm(outer) 2)amnionamnioticcavityamnioticfluid,finallytocovertheumbilicalcordandfetalsideofplacenta 3)3)AmnioticFluidRecirculationAmnioticFluidFetus AmnionUrinationswallowSecretoryAbsorption4)ThefunctionofAmnioticFluidServesasaprotectivecushion.Allowsforfetalmovements.Preventsadherenceoftheembryototheamnion.Maintainsfetalbodystemperature.Dilatescervixandscoursbirthcanalduringparturition. .5)AbnormalityofAmnioticFluid hydramniosorpolyhydramnios:2L，anencephaly,hydrocephalus,esophagealatresia,maternaldiabeteshypamnionoroligohydramnios:500mL,renalagenesis,urethratresia,leadingtoadherence3.YolkSac1)Endoderm+Extra-embryonicmesoderm 2)FunctionEndodermcellsPrimitivegermcellsExtra-embryonicmesodermPrimitivebloodcell;Bloodisland 4.Allantois1)Formationlateralpartofyolksaccaudatopenetrateintotheblindendofconnectingstalk2)ResultsAllantoic arteryandveinUmbilicalarteryandvein5.UmbilicalCord1)Formationconnectingstalkconnectingwithembryoandplacenta,Length:55cm，Diameter:1.5cm(atbirth)2)InclusionsCoveredbyamnion.Mucinousconnectivetissue(inside),containingumbilicalarteries(2)andvein(1),andyolksacandallantoiswithatresia.UmbilicalCord,ChorionandHumanEmbryo11stweek6thweek 5thweek9thweek12ndweek18thweek19thweek7thmonth23rdweek3)UmbilicalCordAbnormalities Longcordfalseknots,umbilicalcordaroundneck Shortcordplacentalabruptionandbleeding“Mask”Boyamnioticbandsorumbilicalcordabnormalities?(2)Placenta1.CompositionFetalportionChorionFrondosum MaternalportionDeciduaBasalis2.PlacentaAtFullTerm1)discoid，d=1525cm,t=2.5cm,w=500g2)fetalsidesmooth，coveredbyamnion.Anumberoflargearteriesandveins,thechorionicvesselsconvergetowardtheumbilicalcord.3)maternalsiderough,1530cotyledons1)chorionicplatechorionicstemcytotrophoblastshell2)decidualplateplacentalseptum(decidualsepta)cotyleidons3)Freedvilli+intervillousspaces,bloodfromspiralartery(maternalblood)3.Structures spiralarteryumbilicalarteriesmaternalbloodintervjllousspace capillary fetus uterinevein umbilicalveins4.BloodCirculation1)theendothelialliningoffetalvessels(chorioniccapillary)anditsbasementmembrane,2)theconnectivetissueinthevilluscore,3)thecytotrophoblasticlayeranditsbasementmembrane,4)thesyncytium5.PlacentalMembraneOrThePlacentalBarrierEarlystageAfter4thmonth6.Function1)MaterialExchanges2)Protection（Blood-PlancetalBarrier）3)HormoneProduction(Endocrine) Humanchorionicgonadotropin(hCG)ProteomicHormoneHuman Placental Lactogen (hPL), or HumanChorionicSomatomammotropin(hCS) ProteomicHormoneProgesterone(Theforthmonths)and E EstrogenSteroidHormoneTwins,MultipleBirths&ConjoinedTwinsDizygoticTwins(FraternalTwins) The result from simultaneous shedding of twooocytesandfertilizationbydifferentspermatozoa.1.eachzygotsdevelopsitsownplacenta,amnionandchorionicsac.2.Occasionally,twoplacentascanbefusedeachother.DizygoticTwinsBlackandWhiteTwinsBecausethetwozygoteshavetotallydifferentgeneticconstitutions,thetwinshavenomoreresemblancethananyotherbrothersorsisters.DizygoticTwinsDizygoticTwinsTwinsDizygoticTwins-fromdifferentspermatozoa(USA,2015)MonozygoticTwins(IdenticalTwins)Theyresultfromsplittingofthezygoteatvariousstagesofdevelopment. CleavagetwoblastocystsEarlyblastocyststwoinnercellmasses BilaminargermdisctwoprimitivestreakThetwocanberecognizedaspartnersofamonozygoticpairbytheirstrongresemblanceinbloodgroups,fingerprints,sex,andexternalappearance,suchaseyeandhaircolor. MonozygoticTwinsTwinsCompetitionTheOldestTwinsMonozygoticTwinsMultipleBirths TripletsMultipleBirths Quadruplets MultipleBirths Quintuplets MultipleBirths SixPregnanciesMultipleBirthsSevenBirths MultipleBirths EightPregnanciesTeratologyConjoinedMalformation CephalopagusConjoinedMalformation ThoracopagusConjoinedMalformation Omphalopagus ConjoinedMalformation ConjoinedMalformation ConjoinedMalformation Dicephalus ConjoinedMalformation (AsymmetricalDuplicity)ConjoinedMalformationConjoinedMalformationinAnimalsCongenitalMalformation(Birthdefect,congenitalanomaly)Aresynonymoustermsusedtodescribestructural,behavioral,functionalandmetabolicdisorderspresentatbirth.1.Geneticfactors2.Environmentalfactors3.Bothoftwofactors1.GeneticFactors1)ChromosomalaberrationsDownssyndrome,Klinefelterssyndrome,Cri-du-chatsyndrome.2)GenemutationsPolycystickidney, microcephaly2.EnvironmentalFactors1)InfectiousAgentsRubella,cytomegalovirus,herpessimplexvirus,varicellavirus,humanimmunodeficiencyvirus(HIV)2)RadiationIonizingradiation3)ChemicalAgentsOrganicmercury,leadandotherheavymetals2.Environmentalfactors4)DrugsThalidomide,Antibiotics5)OthersAlcohol,TobaccofetalalcoholsyndromephocomeliaAirPollutantsandAbnormalityinMammalianReproductiveSystem徐菲菲、马大骅、丁之德徐菲菲、马大骅、丁之德 。空气污染物对哺乳动物生殖和胚胎发育的影响空气污染物对哺乳动物生殖和胚胎发育的影响；国际生殖健康国际生殖健康/ /计划生育杂志计划生育杂志2015; 34(3): 209-2142015; 34(3): 209-214作者单位作者单位 上海交大医学院上海交大医学院20122012级临床医学八年制级临床医学八年制基金资助基金资助 上海交通大学医学院第八期大学生创新项目（上海交通大学医学院第八期大学生创新项目（20140112014011） 第八期国家大学生科创项目第八期国家大学生科创项目SmokingandFetus3.BothEnvironmentalandGeneticReasonsRegionalityandSusceptibility Sensitiveperiodtoteratogenicagents The3rd8thWeek(EmbryonicPeriod)4.PreventionofBirthDefectsPrenataldiagnosisTheFormationofHumanLifeANewHealthyLifeWasBorn！Children,OurFutureIwascomefrommyMon!