扬州大学：《妇产科学》课程教学课件（PPT讲稿）20 前置胎盘 PLACENTA PREVIA

PLACENTA PREVIALinQiDe

PLACENTA PREVIA Lin Qi De

DefinitionPlacenta previa:Abnormallocation of the placenta over ,or inclose proximity to the internal os.Incidence: approximately 1 /250 pregnancynulliparas:1/1000~1/1500 pregnancy1/20grandmultiparas:

Definition Placenta previa: Abnormal location of the placenta over ,or in close proximity to the internal os. Incidence: approximately 1 /250 pregnancy nulliparas: 1/1000~1/1500 pregnancy grandmultiparas: 1/20

ClassificationComplete(total)placentaprevia:entirecervical os iscoveredPartial placentaprevia:the margin of theplacenta extends across but not all of the internal os.Marginal:edge of the placenta lies adjacentto the internal osLow lying placenta:placenta is located near butnot directly adjacent to the internal os

Classification Complete (total) placenta previa: entire cervical os is covered Partial placenta previa:the margin of the placenta extends across but not all of the internal os. Marginal:edge of the placenta lies adjacent to the internal os Low lying placenta:placenta is located near but not directly adjacent to the internal os

EtiologyMechanism:abnormal vascularizationPredisposingfactors:.Twinpregnancy·Increasing maternal ageIncreasingparity·Previouscesareansection

Etiology Mechanism: abnormal vascularization Predisposing factors: •Twin pregnancy •Increasing maternal age •Increasing parity •Previous cesarean section

diagnosisPainless vaginal bleed:first bleeding episode is 29~30 weeksUltrasonography:benefit in localizing the placenta anddiagnosis placenta previa

diagnosis Painless vaginal bleed: first bleeding episode is 29~30 weeks Ultrasonography: benefit in localizing the placenta and diagnosis placenta previa

CautionDouble setup vaginal examinationNo digital vaginal or rectal examination ispreformed in case of placenta previa . Onlyas a final and definitive event and only underconditions of double set up.This procedure involves careful evaluationof the cervix in the operation room with fullpreparations for rapid cesarean section

Caution Double setup vaginal examination No digital vaginal or rectal examination is preformed in case of placenta previa . Only as a final and definitive event and only under conditions of double set up. This procedure involves careful evaluation of the cervix in the operation room with full preparations for rapid cesarean section

ManagementBasicmanagement.Initial hospitalization with hemodynamicstabilizationEnforcedbedrestRestrictionsof activity

Management Basic management •Initial hospitalization with hemodynamic stabilization •Enforced bed rest •Restrictions of activity

Expectantmanagement(allow for further fetalgrowth and maturation)·Blood transfusion is given as necessaryAmniocentesisforfetal lung maturitytesting.Cesarean birth if fetus is thought to bemature

Expectant management (allow for further fetal growth and maturation) •Blood transfusion is given as necessary •Amniocentesis for fetal lung maturity testing •Cesarean birth if fetus is thought to be mature

Indication ofvaginal delivery·Delivery can be accomplished withminimal blood lossFetusisdead?Majorfetal malformation

Indication of vaginal delivery •Delivery can be accomplished with minimal blood loss •Fetus is dead •Major fetal malformation

Complication·Placentapreviaaccreta.Postpartumhemopphage·Increasing maternal mortality and perinatalmortality

Complication •Placenta previa accreta •Postpartum hemopphage •Increasing maternal mortality and perinatal mortality