《妇产科学》前置胎盘 Placenta Previa 英文-教学课件（非AI生成）.ppt

前置胎盘PlacentaPreviaAcommonvaginalbleedinginthirdtrimester

RequirementsMasterthedefinition,types,clinicalmanifestations,diagnosisandtreatmentprinciples.

Befamiliarwiththepathogenesis,pathophysiology,differentialdiagnosis,andmaternalfetaloutcomes.

Understandtheetiologyandprevention.

CaseA34yr-oldpregnancywomanat31weeksisadmittedtotheobstetricward.Shewokeupinthemiddleofthenightinapoolofblood.Nopainoruterinecontractions.Inspectionoftheuterusshowsthefetusappearstransverselie.Fetalhearttonesareregularat145/min.Oninspectionherperineumisgrosslybloody.Diagnosis?Treatment?

GeneralConsiderationDefinitionAfter28weeksgestation,anypartoftheplacentaisimplantedintheloweruterinesegment,evenpartiallyortotallycoveredtheinternalcervicalos.Consequentlytheplacentaisinadvanceofthepresentingpart.

GeneralConsideration

Incidence0.24%~1.57%(ourcountry)0.5%~0.90%(othercountries)Nulliparas:1/1000~1/1500pregnancyGrandmultiparas:1/20pregnancyItisthemajorreasonofhemorrhageinthethirdtrimesterpregnancyGeneralConsideration

Placentapreviastate（胎盘前置状态）28weeks.Asgestationagegoeson,thepositionofplacentawillmovetowardsuterinecavity.GeneralConsideration

EtiologyUncertainHighriskfactors:1.maternalage:35years2.multiparity3.priorcesareandelivery:5times4.smoking

Causes1.Endometrialabnormality1)Scaredorpoorlyvascularizedendometriuminthecorpus.2)Curettage,Delivery,CSandinfectionofendometrium2.Placentalabnormality1)Largeplacenta(multiplepregnancy)2)succenturiatelobe（副胎盘）3.DelayeddevelopmentoftrophoblastcellEtiology

EtiologySuccenturiateplacenta

ClassificationCompleteplacentapreviaPartialplacentapreviaMarginalplacentapreviaCompletePPPartialPPMarginal