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1、FetalMembranesandPlacenta1.Fetalmembranes-chorion,amnion,yolksac,allantois,umbilicalcord(1)Chorion1)FormationSyncytiotrophoblast+Cytotrophoblast+Extra-embryonicMesoderm-Villus2)DevelopmentofVillus PrimaryVilliSecondaryVilliTertiaryVilli,FreeVillitoformOuterCytotrophoblastShell3)ClassificationChorion
2、FrondosumadjacenttoDeciduaBasalis.Villi,suppliedwith bloodfromspiralarterybecomecompactandgrowwell,andfinallytoformfetalsideofplacenta. . ChorionLaeve adjacenttoDeciduaCapsularis.Villi, devoid of blood from spiral artery becomestretchedanddegenerate.4)AbnormalDevelopmentHydatidiformMoleVillishowgrap
3、e-shapedorblister-likestructures,finallyleadingembryotodeath.ChoriocarcinomaTrophoblastcellsbecomemalignanthyperplasia. 2.Amnion 1) Translucentthinmembrane=amnioticcells(inner)+extra-embryonicmesoderm(outer) 2)amnionamnioticcavityamnioticfluid,finallytocovertheumbilicalcordandfetalsideofplacenta 3)3
4、)AmnioticFluidRecirculationAmnioticFluidFetus AmnionUrinationswallowSecretoryAbsorption4)ThefunctionofAmnioticFluidServesasaprotectivecushion.Allowsforfetalmovements.Preventsadherenceoftheembryototheamnion.Maintainsfetalbodystemperature.Dilatescervixandscoursbirthcanalduringparturition. .5)Abnormali
5、tyofAmnioticFluid hydramniosorpolyhydramnios:2L，anencephaly,hydrocephalus,esophagealatresia,maternaldiabeteshypamnionoroligohydramnios:500mL,renalagenesis,urethratresia,leadingtoadherence3.YolkSac1)Endoderm+Extra-embryonicmesoderm 2)FunctionEndodermcellsPrimitivegermcellsExtra-embryonicmesodermPrimi
6、tivebloodcell;Bloodisland 4.Allantois1)Formationlateralpartofyolksaccaudatopenetrateintotheblindendofconnectingstalk2)ResultsAllantoic arteryandveinUmbilicalarteryandvein5.UmbilicalCord1)Formationconnectingstalkconnectingwithembryoandplacenta,Length:55cm，Diameter:1.5cm(atbirth)2)InclusionsCoveredbya
7、mnion.Mucinousconnectivetissue(inside),containingumbilicalarteries(2)andvein(1),andyolksacandallantoiswithatresia.UmbilicalCord,ChorionandHumanEmbryo11stweek6thweek 5thweek9thweek12ndweek18thweek19thweek7thmonth23rdweek3)UmbilicalCordAbnormalities Longcordfalseknots,umbilicalcordaroundneck Shortcord
8、placentalabruptionandbleeding“Mask”Boyamnioticbandsorumbilicalcordabnormalities?(2)Placenta1.CompositionFetalportionChorionFrondosum MaternalportionDeciduaBasalis2.PlacentaAtFullTerm1)discoid，d=1525cm,t=2.5cm,w=500g2)fetalsidesmooth，coveredbyamnion.Anumberoflargearteriesandveins,thechorionicvesselsc
9、onvergetowardtheumbilicalcord.3)maternalsiderough,1530cotyledons1)chorionicplatechorionicstemcytotrophoblastshell2)decidualplateplacentalseptum(decidualsepta)cotyleidons3)Freedvilli+intervillousspaces,bloodfromspiralartery(maternalblood)3.Structures spiralarteryumbilicalarteriesmaternalbloodintervjl
10、lousspace capillary fetus uterinevein umbilicalveins4.BloodCirculation1)theendothelialliningoffetalvessels(chorioniccapillary)anditsbasementmembrane,2)theconnectivetissueinthevilluscore,3)thecytotrophoblasticlayeranditsbasementmembrane,4)thesyncytium5.PlacentalMembraneOrThePlacentalBarrierEarlystage
11、After4thmonth6.Function1)MaterialExchanges2)Protection（Blood-PlancetalBarrier）3)HormoneProduction(Endocrine) Humanchorionicgonadotropin(hCG)ProteomicHormoneHuman Placental Lactogen (hPL), or HumanChorionicSomatomammotropin(hCS) ProteomicHormoneProgesterone(Theforthmonths)and E EstrogenSteroidHormone
12、Twins,MultipleBirths&ConjoinedTwinsDizygoticTwins(FraternalTwins) The result from simultaneous shedding of twooocytesandfertilizationbydifferentspermatozoa.1.eachzygotsdevelopsitsownplacenta,amnionandchorionicsac.2.Occasionally,twoplacentascanbefusedeachother.DizygoticTwinsBlackandWhiteTwinsBecauset
13、hetwozygoteshavetotallydifferentgeneticconstitutions,thetwinshavenomoreresemblancethananyotherbrothersorsisters.DizygoticTwinsDizygoticTwinsTwinsDizygoticTwins-fromdifferentspermatozoa(USA,2015)MonozygoticTwins(IdenticalTwins)Theyresultfromsplittingofthezygoteatvariousstagesofdevelopment. Cleavagetw
14、oblastocystsEarlyblastocyststwoinnercellmasses BilaminargermdisctwoprimitivestreakThetwocanberecognizedaspartnersofamonozygoticpairbytheirstrongresemblanceinbloodgroups,fingerprints,sex,andexternalappearance,suchaseyeandhaircolor. MonozygoticTwinsTwinsCompetitionTheOldestTwinsMonozygoticTwinsMultipl
15、eBirths TripletsMultipleBirths Quadruplets MultipleBirths Quintuplets MultipleBirths SixPregnanciesMultipleBirthsSevenBirths MultipleBirths EightPregnanciesTeratologyConjoinedMalformation CephalopagusConjoinedMalformation ThoracopagusConjoinedMalformation Omphalopagus ConjoinedMalformation Conjoined
16、Malformation ConjoinedMalformation Dicephalus ConjoinedMalformation (AsymmetricalDuplicity)ConjoinedMalformationConjoinedMalformationinAnimalsCongenitalMalformation(Birthdefect,congenitalanomaly)Aresynonymoustermsusedtodescribestructural,behavioral,functionalandmetabolicdisorderspresentatbirth.1.Gen
17、eticfactors2.Environmentalfactors3.Bothoftwofactors1.GeneticFactors1)ChromosomalaberrationsDownssyndrome,Klinefelterssyndrome,Cri-du-chatsyndrome.2)GenemutationsPolycystickidney, microcephaly2.EnvironmentalFactors1)InfectiousAgentsRubella,cytomegalovirus,herpessimplexvirus,varicellavirus,humanimmuno
18、deficiencyvirus(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
19、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!
