羊水栓塞：
Amnionicfluidembolism
Amnionicfluidentersthecirculationasaresultofabreachinthephysiologicalbarrierthatnormallyexistsbetweenmaternalandfetalcompartments.Sucheventsappeartobecommon,ifnotuniversal,withbothsquamesofpresumedfetaloriginandtrophoblastsbeingcommonlyfoundinthematernalcirculation.Theremaybematernalexposuretovariousfetalelementsduringtrauma,ormorecommonlyduringlaborordeliveryassmalllacerationsdevelopintheloweruterinesegmentorcervix.Alternately,cesareansectionaffordsampleopportunityformixtureofmaternalbloodandfetaltissues.
子宫破裂：
uterinerupture
uterinerupturemaydevelopasaresultofpreexistinginjuryoranomaly,itmaybeassociatedwithtrauma,oritmaycomplicatelaborinapreviouslyunscarreduterus.
Ruptureoftheuterusmaycommunicatedirectlywiththeperitonealcavity（complete）ormaybeseparatedfromitbythevisceralperitoneumovertheuterusorthatofthebroadligament（incomplete）.
胎膜早破:
PretermRupturedMembranes.Anintenseinflammatoryreactionatthesiteofprematurelyrupturedmembraneswasnotedasearlyas1950,andthissuggestedinfection.McGregorandcolleagues（1987）demonstratedthatinvitroexposuretobacterialproteasesreducedtheburst-ingloadoffetalmembranes.Thus,microorganismsgivenaccesstofetalmembranesmaybecapableofcausingmembranerupture,pretermlabor,orboth.
BacterialVaginosis.Bacterialvaginosisisaconditioninwhichthenormal,lactobacillus-predominantvaginalfloraisreplacedwithanaerobicbacteria,Gardnerellavaginalis,andMycoplasmahominis（Hillierandcol-leagues,1995）.Diagnosticfeaturesinclude（1）vaginalpHgreaterthan4.5,（2）anamineodorwhenvaginalse-cretionsaremixedwithpotassiumhydroxide,（3）vagi-nalepithelialcellsheavilycoatedwithbacilli（"cluecells"）,and（4）fewwhitecellswithamixedflora（ascomparedwiththenormalpredominanceoflacto-bacilli）onGramstainingofvaginalsecretions.Bacterialvaginosishasbeenassociatedwithpretermbirth,pretermrupturedmembranes,infectionofthechorionandamnion,aswellasamnionicfluidinfection（Hillierandcolleagues,1995）.Platz-Christensenandcolleagues（1993）haveprovidedsomeevidencethatbacterialvagi-nosismayprecipitatepretermlaborbyamechanismsimilartothecytokinenetworkpathwayproposedforamnionicfluidbacteria（Pig.34-4）.Incontrast,Thorsenandassociates（1996）,inaprospectivestudyof3600Danishwomen,foundthatbacterialvaginosisdiagnosedbefore24weekswasnotrelatedtorupturedmembranesbefore37weeksortolowbirthweight.
