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