1

ZuckerbergSanFranciscoGeneralHospital(ZSFG)LaborDurationand

ManagementGuidelineAnaDelgado,CNM,JyeshaWrenSerbin,CNM,andAnnaYenTran,CNM

BackgroundAthirdofallbabiesintheU.S.arebornbycesareandelivery,aratetwiceashighaswhattheWorldHealthOrganizationdeemsappropriateforhighlydevelopedcountries.1Whilecesareandelivery(CD)isalife-savingprocedureinsomesituations,itsoveruseintheUnitedStatesiscurrentlycontributingtounduemorbidityandmortalityformothersandbabies.CDareassociatedwithathree-foldincreaseinseverematernalmorbiditiessuchashemorrhagerequiringhysterectomyortransfusions,uterinerupture,anestheticcomplications,shock,cardiacarrest,acuterenalfailure,assistedventilation,venousthromboembolism,majorinfection,andin-hospitalwoundorhematoma.2Furthermore,subsequentcesareandeliveriesincreasetheriskofplacentalabnormalitiesinfuturepregnancies.Bythethirdcesareandelivery,awomanhasa3%chanceofplacentapreviaandthereisa40%chancethattheplacentapreviawillbecomplicatedbyplacentaaccreta.2Labordystociaisthetopindicationforprimarycesareandeliveries.1However,manyoftheinterventionsusedtotreatlabordystocia,suchasoxytocinaugmentationandartificialruptureofmembranes,putwomenatriskforothermorbiditiesandinsomecasesdecreasedpatientsatisfaction.Thisguidelineisintendedtoaidhealthcareprovidersinidentifyingthoseatriskforlabordystocia,andprovidethemwithatemplateforjudicious,safeandtimelymanagementoflabordystociaandarrest.

RelevantDataActivePhaseArrest

Inthesettingofactivephasearrest(APA),outcomesofvaginaldeliveryandcesareandeliverywerecompared.3Abnormalactivephasewasdiagnosedaftergreaterthanorequalto4cmcervicaldilationwithnoprogressforatleast2hoursinthepresenceofadequateuterinecontractions(≥200Montevideounitsper10-minuteperiod,asmeasuredbyanintrauterinepressurecatheter).Asampleof1,014women,355inthevaginaldeliverygroup,95intheoperativevaginaldeliverygroup,and584inthecesareandeliverygroupyieldedthefollowingresults:

NeonatalOutcomes:● Nodifferenceinratesofadverseneonataloutcomesbetweenthosewhodelivered

vaginallyandthosewhohadacesareandelivery

MaternalOutcomes:WomenwithAPAwhohadcesareanscomparedwithwomenwithAPAwhodeliveredvaginally,wereathigherriskof

● Chorioamnionitis (OR3.3795%CI2.21-5.15)● Endometritis (OR48.4,95%CI6.61-354)● Postpartumhemorrhage (OR5.18;95%CI3.42-7.85)● Severepostpartumhemorrhage (OR14.97,95%CI1.77-1.26)3

2

Theresearchersalsostudiedtheoutcomesof355womenwithvaginaldeliveriesinthesettingofAPAcomparedto12,566womenwithoutAPA.ThewomenwithAPAhad:

MaternalOutcomes● HigherrateofOperativevaginaldelivery(28%vs.17%,p<0.001)● Higherrateofchorioamnionitis(18%v.8%,p<0.001)● Higherrateof3rdand4thdegreelacerations(16%vs.9%,p<0.001)● HigherrateofPostpartumhemorrhage(26%vs.17%,p<0.001)

NeonatalOutcomes:● Higherrateofshoulderdystocia(4%vs.2%,p<0.01)● Higherrateof5minuteApgarscores<7(5%vs.2%,p<0.001)● Nodifferenceinsepsis,NICUadmission,clavicularfracture,Erb’spalsyoracidemia.3

Summary:Womenwhohadactivephasearresthadhigherrisksofmaternalandneonataloutcomescomparedtothosewhodidnothavethediagnosis.However,thosewhohadactivephasearrestandunderwentacesareandeliveryhadmuchhigherrisksthanthosewhodeliveredvaginally.Waitingforavaginaldeliveryratherthandoingacesareandecreasestheriskofadversematernaloutcomeswithoutcausinganyadditionalrisktothenewborn.Numberneededtotreat(NNT):threewomendeliveringvaginallyratherthanbycesareanwouldpreventonepostpartumhemorrhage;33womendeliveringvaginallywouldpreventonebloodtransfusion.

ProlongedSecondStage

Nulliparouswomen:Multipleinvestigatorshavefoundthatfornulliparouswomen,adverseneonataloutcomesarenot

associatedwithdurationofsecondstage.2Asecondaryanalysiscomparedneonatalandmaternaloutcomesof4,126nulliparouswomenwithsecondstagesoflaborlastinggreaterthan3hourswithwomenwhodeliveredinunder3hours.

Results:Therewerenoincreasesinneonataloutcomesofprolongedsecondstagefor:

● NICUadmission● 5minuteApgarscores<4● umbilicalcordpH<7● intubation● sepsis● smallincreaseinbrachialplexusinjury(OR1.78CI1.08-2.78)

○ smallabsoluterisk(3in1000)MaternaloutcomesLonger2ndstageassociatedwith:

● higherratechorioamnionitis(OR1.60,CI1.51-1.87)● 3rdor4thdegreelaceration(OR1.88,CI1.62-1.99)● uterineatony(OR1.29,CI1.51-1.45)4

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Multiparouswomen:Aretrospectivecohortstudyof5158womenfoundthatformultiparouswomenwith3hoursormoreinsecondstage,therewereincreasedrisksof:

MaternalOutcomes:● 3rdand4thdegreelaceration(OR2.56;95%CI[1.44-4.55]● postpartumhemorrhage(OR2.27;95%CI[1.66-3.11]● chorioamnionitis[OR6.02;95%CI[4.14-8.75]

NeonatalOutcomes:● 5-minuteApgarscoreoflessthan7(OR3.63;95%CI[1.77-7.43]● NICUadmission(OR2.08;95%CI[1.15-3.77]● Compositeofneonatalmorbidity(OR1.85;95%CI[1.23-2.77]● Longerneonatalstayinthehospital(OR1.67;95%CI[1.11-2.51]5

Apopulation-basedstudyincluding2,156multiparouswomenwithprolongedsecondstage(definedaslastingmorethan2hours)foundsimilarresultsbutnodifferencein:

● neonatalsepsis● trauma6

ChanceofNSVDbylengthsofsecondstage:

● at3hours: 59%● at4hours: 27%● at5hours: 9%4

Accordingtoa2014retrospectivecohortstudyof42,268womenwhodeliveredvaginallyandhadnormalneonataloutcomes,the95thpercentiledurationofsecondstagelaborwithepiduralanesthesiaismorethantwohoursgreaterforbothnullipsandmultips(asopposedtoonehour)whencomparedtowomeninsecondstagelaborwithoutepiduraluse.7Summary:Inprolongedsecondstagefornulliparouswomen,thereishigherriskofadversematernaloutcomesbutnoevidenceofadverseneonataloutcomes.Formultiparouswomenwithprolongedsecondstage,thereareincreasedrisksformaternalandneonataloutcomes.Assecondstageprogressespastthenormalrange,thereisadecreasingchanceofasuccessfulvaginaldelivery.

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NewInsightfromContemporaryDataonNormalLaborCurveTraditionally,normalrangesforthedurationofthestagesoflaborhavebeenbasedondatafromFriedman’sstudiesinthe1950’s.8ResearchfromZhanghasupdatedourunderstandingofwhatisnormalforcontemporarywomenintermsoflaborduration.9Likelythemostsignificantnewunderstandingisthat,formostwomen,activelabordoesn’tbeginuntilsixcentimetersofcervicaldilation,notthreecentimetersasthoughtbyFriedman.AccordingtoZhangetal,halfofwomenarenotyetactiveat4-5cmdilation.Thustheyrecommendusing6cmasthestartoftheactivephaseoflabor.Anotherkeytake-awayfromthiscontemporarydataisthatfornulliparouswomen,laboracceleratesatgreaterdilationsbutthereisnoclearinflectionpointaspreviouslythought.Inmultiparaslaborgenerallyacceleratesafter6cmdilation.Additionally,Zhangandcolleagueshighlightthatusingthe“average”astheparameterforguidinglabormanagementdecisionsisnotsuitableforthemanagementoftheindividualpatient.Rather,womenshouldbecomparedtothelongestnormaldurationthatisstillassociatedwithhealthybirthoutcomes(alsoknownas95thpercentilevalues)forthefirstandsecondstagesoflabor.SeeZhang’slaborcurvechartinAppendixAformedianand95thpercentiledurationsforcervicaldilation.

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LaborDurationDefinitions

FirstStageLatentLabor:Cervicaldilationof0-6cm9

Normal Difficulttodefineduetochallengeofdeterminingtheonsetoflabor.• Norangeexistsforthenewlatentlabordefinitionof0-6cmperZhang

o Nulliparas(dataexistsonlyfor3-6cm):Mediandurationof3.9hours;95thpercentile:17.7hours

o Multiparas(dataexistsonlyfor4-6cm)Mediandurationof2.2hours;95thpercentile:10.7hours9

• PerFriedman:<20hoursinthenullipara,and<14hoursinthemultiparafrom0-3cm8

Prolonged ● Norangeexistsforthenewlatentlabordefinitionof0-6cm○ Nulliparas:>18hoursfrom3-6cm○ Multiparas:>10.7hrsfrom4-6cm9

● PerFriedman:>20hoursinthenullipara,>14hoursinthemultiparafrom0-3cm8

FirstStageActiveLabor:Cervicaldilationof6-10cm9

Normal ● Nulliparas:Mediandurationof2.1hours;95thpercentile:7hours● Multiparas:Mediandurationof1.5hours;95thpercentile:5.1hours9

Prolonged/slowslope

● Slowprogressfrom6-10cm:Presenceoflaborprogress,butdurationoutsidethe95thpercentilerangeofnormal(>7hoursinanullipara,or>5hoursinamultipara)9

Arrest Absenceoflaborprogress/progressivecervicaldilationfor:● 4hoursORMOREofadequateUCs(MVUs>200)● 6hoursORMOREwithPitocinandrupturedmembranes(ifpossible)ifUCs

inadequate2

SecondStageLabor:Completedilationtobirthoftheneonate

Normal* ● Nulliparas:<3hoursWITHOUTepidural,<4hoursWITHepidural● Multiparas:<2hoursWITHOUTepidural,<3hoursWITHepidural1

*Newdatafrom2014suggeststhat95%ofnullipswithepiduralswilldeliversafelywithin5hoursand19minutesand95%ofmultipswilldeliversafelywithin5hours.7

Prolonged Presenceofdescent,butdurationoutsidenormalrange.• Nulliparas:>3hourswithoutepidural,>4hourswithepidural• Multiparas:>2hourwithoutepidural,>3hourswithepidural1

Arrest Nodescentaftergoodpushingeffortsfor:Nulliparas:>3hourswithoutepidural,>4hourswithepiduralMultiparas:>2hourwithoutepidural,>3hourswithepidural

GeneralConsiderations

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TeamConsiderations

Concernsregardinglaborprogressandneedforpotentialinterventionoroperativedeliveryduetolabordystociashouldbecommunicatedfrequentlyandopenlytoallteammembers.CareshouldbetakentoaddresstimingandresourceutilizationwithsituationalawarenessaboutotherpatientcareactivitiesattheBirthCenter.

RiskFactorsforDystociaBeforeandDuringLaborBasedonACOGPracticeBulletinNumber4910,exceptwhereitisnotedotherwise.

RiskFactorspriortolabor Riskfactorsduringlabor

NulliparityObesityPosttermpregnancyFetalweight>4kgAdvancedmaternalageDiabetesHypertensionInfertilitytreatmentPreviousperinataldeathAmnioticfluidabnormalitiesPrematureruptureofmembranesSleepdeprivation11Riskfactorsspecifictosecondstage:Shortmaternalheight(<5ft)

InductionoflaborEpiduralChorioamnionitisPersistentocciputposteriorpositionCephalopelvicdisproportionDehydration12Riskfactorsspecifictosecondstage:LongerfirststageoflaborHighstationatcompletecervicaldilatation(higherthan+2stationatcomplete)

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TheP’sofLaborProgressThe7P’sofLaborProgress:

RemembertoconsiderALLoftheseareaswhenevaluatinglabordystocia.● Powers:contractions,pushing● Passage:pelvicdimensions/shape● Passenger:position,attitude,size● Position&Movement(maternal)● Psyche:coping● Partner/support:supportivepartner,family,doula● Provider:yourownbeliefs,attitudes,practices,stateofmind

Etiologiesandriskfactorsfordysfunctionallabor

TableadaptedfromSimpkinandAncheta’sLaborProgressHandbook,ThirdEdition.13

Etiology Description Comments

Cervicaldystocia Posteriorunripecervixatlaboronset;scarred,fibrouscervixor“rigidos”;“tensecervix”orthickloweruterinesegment

Unripecervixmayprolonglatentphase.Surgicalscarring,damagefromdisease,orstructuralabnormalitymayincreasecervicalresistance

Emotionaldystocia Maternaldistressorfear,exhaustion,severepain

Increasedcatecholamineproductionmayinhibitcontractions

Fetaldystocia Malposition,asynclitism,largeordeflexedhead,lackofengagement

Pendulousabdomen,sizeandshapeofpelvisorfetalheadmaypredisposefetustomalposition

Iatrogenicdystocia Misdiagnosisoflabororsecondstage,electiveinduction(nulliparous),inappropriateoxytocinuse,maternalimmobility,drugs,dehydration,disturbance

Misdiagnosisorunneededinterventionsorrestrictionscansloworinterferewithlaborprogress

Pelvicdystocia Malformation,pelvicshapeotherthangynecoid,smalldimensions

Maternalmovementanduprightpositionsincreasepelvicdimensions

Uterinedystocia Inadequateorinefficientcontractions Maybesecondarytofear,fasting,dehydration,supineposition,cephalopelvicdisproportion,lacticacidosisinmyometrium,orstructuralabnormalities

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ManagementGuidelines

FirstStage:LatentLabor0-6cmDefinitionofLatentlabor:Thepointatwhichthewomanperceivesregularuterinecontractionsuptothebeginningofactivephase.

Difficulttodefineduetochallengeofdeterminingtheonsetoflabor.o Norangeexistsforthenewlatentlabordefinitionof0-6cmperZhang

o Nulliparas(dataexistsonlyfor3-6cm):Mediandurationof3.9hours;95thpercentile:17.7hours

o Multiparas(dataexistsonlyfor4-6cm)Mediandurationof2.2hours;95thpercentile:10.7hours9

o PerFriedman:<20hoursinthenullipara,and<14hoursinthemultiparafrom0-3cm8

Management:Managementisbasedonmaternalcoping,membranestatus,fetalstatus,parity,andinfectiousdiseaserisk.ForALLpatients:

● Involvepatientandfamilyincareplanandshareddecisionmaking.● Encouragecontinuouslaborsupport.Continuouslaborsupporthasbeenshowntoshortenlabor

andpromotephysiologicbirth.(SeeAppendixB:ContinuousLaborSupport)● Delayhospitaladmissionuntilactivephase:

○ Recommendedadmissioncriteria:admitat4-5cmIFexamshaverevealedcervicalchangeof>0.5cm/hrovertimeORat6cmregardlessofprecedingrateofcervicalchange.14

○ Ifsendinghome,counselre:earlylabormanagementathome,copingstrategies,dangersigns,andwhentoreturntothehospital.Womensenthomeinearlylaborreportedthattheywouldhavefeltmorereassurediftheyhadreceiveddetailedspecificwritteninstructionsandafollowupphonecall.15

● Rest● Encouragenutrition/hydration● Encourageuprightpositions(standing,walking,kneeling,sitting)(SeeAppendixC:Upright

PositioningDuringLabor)● Waterimmersion:Onehourofimmersioninwaterwasassociatedwithshorterlaborsevenwhen

initiatedinlatentlabor.(SeeAppendixD:WaterImmersion)● Avoidamniotomy(SeeAppendixE:Amniotomy)

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LatentLabor-Prolonged:● Norangeexistsforthenewlatentlabordefinitionof0-6cm

○ Nulliparas:>18hoursfrom3-6cm○ Multiparas:>10.7hrsfrom4-6cm9

● PerFriedman:>20hoursinthenullipara,>14hoursinthemultiparafrom0-3cm8

Management:Forpatientswithriskfactorsortrendingtowardsdystocia:

1. MembraneSweeping(SeeAppendixF:MembraneSweeping)2. Breast/nipplestimulation(SeeSFGHBirthCenterPolicy2.24)3. Encourageuprightpositions(standing,walking,kneeling,sitting)(SeeAppendixC:

UprightPositioningDuringLabor)Threeoptionsforprolongedlatentlabor:

1.ExpectantManagement:Observe,ambulate,orsendhome.2.Sedation:Considertherapeuticrest(seetriageordersetfordosingrecommendations)3.Stimulationoflabor:Stimulationisreasonabletoconsiderinwomenwitharipecervixorin

womenwhohavefailedtherapeuticrestandhavepresentedformultipletriagevisits:considervariousmethodsofinduction/augmentation.Formoreinformationonoxytocin,seeSFGHoxytocinpolicy.

a. Mostwomenwithprolongedlatentphasewillenteractivephasewithexpectantmanagementalone.Thosethatdon’twillofteneither1)stopcontracting,or2)reachactivephasewithamniotomyoroxytocinorboth.Thusprolongedlatentphaseisnotanindicationforcesareandelivery.2

b. Ifpatientisbeinginduced,considerfailedinductionifunabletogenerateUC’sq3minutesafteratleast24hoursofpitocinwithrupturedmembranes,iffeasible.1

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FirstStage:ActiveLabor6-10cm

Definition:Pointatwhichthelaborcurvebecomessteep,withsteadyandrapidcervicalchange.Exactpointinlaborvariesconsiderablyfrompersontoperson.

NormalActiveLabor:○ Nulliparas:Mediandurationof2.1hours;95thpercentile:7hours○ Multiparas:Mediandurationof1.5hours;95thpercentile:5.1hours9

Management:ForALLpatients● Involvepatientandfamilyincareplanandshareddecisionmaking.● Encouragecontinuouslaborsupport.Continuouslaborsupporthasbeenshownto

shortenlaborandpromotephysiologicbirth.(SeeAppendixB:ContinuousLaborSupport)

● Supportivecare:○ Hydration:EncouragePOfluids(notexclusivelywater)andofferIVfluidsifPOfluidintakeislow.BewareofoveruseofIVhydration,considermaintainingtotalIVfluidintakebelow125anhourunlessclinicallyindicated.

○ Nourishment:Offersmallportionsoffoodthatsoundappealingtothelaboringmother.Eg:fruit,yogurt,crackers,cheese,popsicles,sandwich.Anaverageof81calorieskcal/hrpreventsthedevelopmentofketosisduringlabor.16

● Encouragemovementandfrequentpositionchanges.Encourageuprightpositions(standing,walking,kneeling,sitting)(SeeAppendixB:UprightPositioningDuringLabor)

● ProvidepsychologicalsupportOptionalInterventions:

● AcupressureofSP6and/orL14point(SeeAppendixG:Acupressure)

ActiveLabor-Prolonged/SlowSlope● Slowprogressafter6cmdilation:Presenceoflaborprogress,butdurationoutsidethe95thpercentile

rangeofnormal(>7hoursinanullip,or>5hoursinamultipara).9

● Considerallpossibleetiologieswhentroubleshooting● Involvethepatientandfamilyinthecareplanandshareddecisionmaking.

Emotionaldystocia:Assessmom’slevelofcoping.Isshedistressed,afraid,exhausted,inseverepain?

● Assessmother’semotional/psychologicalwellbeingthroughopen-endedquestionsandactivelistening,andprovideappropriatereassuranceandeducation.Betweencontractionsaskquestionslike:

○ Whatwasgoingthroughyourmindduringthatlastcontraction?○ Howareyoufeelingrightnow?○ Doyouhaveanyideawhyyourlaborhassloweddown?○ Isthereanythingthatyoufeelneedstohappenbeforeyouhaveyourbaby?

● Refocusandcomfortpatient:shower/bath,massage/soothingtouch,aromatherapy● Painrelief:Ideallystartingwithnon-pharmmethodsandescalatingasneeded.● Encouragecontinuouslaborsupport.Continuouslaborsupporthasbeenshowntoshorten

laborandpromotephysiologicbirth.(SeeAppendixB:ContinuousLaborSupport)

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Cervicaldystocia:Persistentanteriorcervicallip,swollencervix,orrigidos?● Withfreedomofmovementmomwilloftenassumepositionsthathelptoreducecervical

lipandswollencervix.○ Gravityneutraloranti-gravitypositionslikehandsandkneesandopenkneechestwillhelptoliftthefetalheadawayandreducepressureonthecervix.○ Tohelpredistributethepressureonthecervixandpromotemoreevendilation,trythefollowing:side-lying,semi-prone,standing.

● Waterimmersionreducesgravitationalforceandcanhelprelievepressureonthecervix.● Ifpatience,positionchange,andwaterimmersionfail,trymanualreductionofapersistentcervicallip.13

Uterinedystocia:Assessforinadequateorinefficientcontractions

● ConsiderIVfluidsifnotalreadyrunning.IVhydrationisshowntoshortenactivelaborby1hr.and2ndstageby15min.Alsodecreasesneedforoxytocinaugmentation(50%w/POfluidsvs.20%w/IVF)12

● Breast/nipplestimulation(SeeSFGHBirthCenterPolicy2.24)● Ensureadequateforces

○ Ensureadequateforces:MVUof200isthoughttobeadequate(ACOG)or,ifnoIUPC,UCsevery2-3minx80-90secthatpalpatestrong○ ConsiderIUPCplacement○ Consideroxytocinaugmentation

■ Considermembranesweepinginconjunctionwithoxytocinaugmentation(SeeAppendixE:MembraneSweeping)

Fetaldystocia:Assessformalposition,CPD,andmacrosomia

● Repositionfetus:Uprightandforwardleaningpositions,walk/movement,pelvicrock,lunge,handsandknees.Suggestfrequentpositionchange(q30min.)13(SeeAppendixC:UprightPositioningDuringLabor)

● Iftheprecedingmeasuresdonotimprovefetalpositionand/ordilation:Assessfetalpositionbyultrasound,ifOPand>7cmdilated,considermanualrotation.(SeeAppendixF:OcciputPosteriorPosition,SeeAppendixG:ManualRotation)

Iatrogenicdystocia:

● Hasactivelaborbeendiagnosedtooearly?Pelvicdystocia:Thisisadiagnosisofexclusionandshouldnotbemadepriortoinvestigatingallothercauses.Note:Operativedeliveryisnotindicatedforprolongedlaboraslongasmaternal/fetalstatusisreassuring.Whenevaluatinglaborprogressconsidereffacement,station,androtationinadditiontocervicaldilation.

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ActivePhaseArrest● Absenceoflaborprogress/progressivecervicaldilationfor:

○ 4hoursORMOREofadequateUCs(MVUs>200)○ 6hoursORMOREifUCsinadequate1

IfActivePhaseArrest:● Involvepatientandfamilyincareplanandshareddecisionmaking.● Managementoptionsinclude:

1. Augmentation:a. Consideroxytocinaugmentationand“tinctureoftime”.b. Canconsideramniotomyasanalternativeoradjuncttooxytocinc. IUPCmaybeusefulindiagnosingadequateforcesbutisnotnecessarytotitrate

Pitocin.d. Incasesofactivephasearrest,waitingforavaginaldeliveryratherthandoinga

cesareandecreasestheriskofadversematernaloutcomeswithoutcausinganyadditionalrisktothenewborn.3

2. Cesarean:Considerifpt.meetsarrestcriteriaandruptureofmembraneshasalreadyoccurred.

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SecondStageLaborDefinition:Timeofcompletecervicaldilatationtobirthoftheneonate.

NormalSecondStage*● Nulliparas:<3hoursWITHOUTepidural,<4hoursWITHepidural● Multiparas:<2hoursWITHOUTepidural,<3hoursWITHepidural1

*Newdatasuggeststhat95%ofnullipswithepiduralswilldeliversafelywithin5hoursand19minutesand95%ofmultipswilldeliversafelywithin5hours.7

Generalmanagement:● Ensureadequatehydration● Encourageuprightandcomfortablepositioning● Allowforthephysiologicrestingphaseandpassivedescent.● Delayedpushing:allowmothertorestuntilstrongurgetopushisnoted—usually1-2hours

○ Especiallybeneficialfor:epiduralw/nourgetopush,fetalheadabove+2stationatonsetof2ndstage,womenw/limitedstrengthormotivationtopush.

○ Delayedpushingdecreasedpushingtimeby20minswhileincreasingdurationof2ndstageby54mins.Nodifferenceinoperativevaginaldeliveryrate.17

● Evaluateprogressearlyandfrequently:expectsomeprogresseachhourofactivepushing.

ProlongedSecondStage:Presenceofdescent,butdurationoutsidenormalrange.• Nulliparas:>3hoursWITHOUTepidural,>4hoursWITHepidural• Multiparas:>2hoursWITHOUTepidural,>3hoursWITHepidural1

Itmaybeprudenttobeginassessingandaddressingpotentialcausesofslowprogressoncesecondstagehasextendedpastthehalf-waypointoftheupperlimitofnormal:

● Nulliparas:>1.5hoursWITHOUTepidural,>2hoursWITHepidural● Multiparas:>1hourWITHOUTepidural,>1.5hoursWITHepidural

Ingeneral,considerallofthesamefactorslistedforprolongedactivefirststagelabor,withthefollowingexceptionsandspecifications:Uterinedystocia:

● Encouragewalkingorpositionchanges● Consideraugmentationwithbreast/nipplestimulationoroxytocin● IUPClikelynotusefulinpushingphase,butmayconsiderduringpassivedescentifconcernedabout

uterinehypocontractility.Fetaldystocia:Assessformalposition,CPD,andmacrosomia

● Encourageupright,forwardleaning,pelvic-openingpositions.(SeeAppendixB:UprightPositioningDuringLabor)

● Checkfetalpositionwithultrasound,andconsidermanualrotationoftheocciputposteriorfetus.(SeeAppendixH:OcciputPosteriorPosition,SeeAppendixI:ManualRotation)

IneffectivePushing:

● Considerdecreasingmaternalanesthesia,althoughevidencere:effectivenessofthisisinconclusive.● Ifpainisinterfering,considerincreasinganalgesiaatleasttemporarilytorefocus

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Arrestofdescent:Nodescentaftergoodpushingeffortsfor:Nulliparas:>3hourswithoutepidural,>4hourswithepiduralMultiparas:>2hourwithoutepidural,>3hourswithepidural

Ifarrestofsecondstage:● Considerallthesamefactorsaswerenotedintheabovesectiononprolongedsecondstage● Consideroperativedelivery.Beawareofriskfactorsforshoulderdystocia.

Aspecificabsolutemaximumlengthoftimespentinthesecondstageoflaborbeyondwhichallwomenshouldundergooperativedeliveryhasnotbeenidentifiedaslongasfetalheartratepatternarenormalandsomedegreeofprogressismade.---ACOG,2003,2014(Strongrecommendation,low-qualityevidence)2ItisimportanttoassessfetalpositioninthesettingofabnormalfetaldescentandmanualrotationoftheOPfetusisareasonableoptiontoconsiderbeforemovingontooperativedeliveryorcesareandelivery.---ACOG,2014(Strongrecommendation,moderatequalityevidence)2

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AppendixA:NormalLaborCurveDurationofLaborinHoursbyParityinSpontaneousOnsetofLabor:

ContemporaryPatternsofSpontaneousLaborwithNormalNeonatalOutcomes9

CervicalDilation(cm) Parity0 Parity1 Parity2+

3-4 1.8(8.1)

4-5 1.3(6.4) 1.4(7.3) 1.4(7.0)

5-6 0.8(3.2) 0.8(3.4) 0.8(3.4)

6-7 0.6(2.2) 0.5(1.9) 0.5(1.8)

7-8 0.5(1.6) 0.4(1.3) 0.4(1.2)

8-9 0.5(1.4) 0.3(1.0) 0.3(0.9)

9-10 0.5(1.8) 0.3(0.9) 0.3(0.8)

2ndstagewithepidural 1.1(3.6) 0.4(2.0) 0.3(1.6)

2ndstagewithoutepidural

0.6(2.8) 0.2(1.3) 0.1(1.1)

Key:Dataaremedian(95thpercentile)Source:Zhang,20109

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AverageLaborCurve

Source:Zhang,20109

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AppendixB:ContinuousLaborSupport

Continuouslaborsupportisanevidence-basedinterventionshowntoshortenlabor,alongwithotherbenefits.In2013TheCochraneCollaborationconductedareviewoftheliteratureoncontinuoussupportforlaboringwomen.18Thereviewincludedtwenty-twotrialsinvolving15,288women.Thissystematicreviewfoundthatcontinuouslaborsupportisassociatedwiththefollowingbenefits:

• Greaterincidenceofspontaneousvaginalbirth(RR1.08,95%confidenceinterval(CI)1.04to1.12).• Lowerratesofintrapartumanalgesia(RR0.90,95%CI0.84to0.96).• Greatermaternalsatisfaction(RR0.69,95%CI0.59to0.79).• Shorterlabor(MD-0.58hours,95%CI-0.85to-0.31).• Lowerratesofcesarean(RR0.78,95%CI0.67to0.91).• Lowerratesofinstrumentalvaginalbirth(fixed-effect,RR0.90,95%CI0.85to0.96).• Lowerratesofregionalanalgesia(RR0.93,95%CI0.88to0.99).• Fewercasesoflowfive-minuteApgarscores(fixed-effect,RR0.69,95%CI0.50to0.95).

Laborsupportdidn'tappeartoaffectanyotherintrapartuminterventions,maternalorneonatalcomplications,orbreastfeeding.Thereviewfoundthatcontinuoussupporthadthegreatestpositiveeffectwhenprovidedbyapersonoutsideofthelaboringwoman'sfamilyorsocialgroup,andnotamemberofthehospitalstaff.18

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AppendixC:UprightPositioningduringLaborItiscommonforwomentolaborinbed,yetthereisnoevidenceindicatingthatthisisbeneficialfor

womenorneonates.Incountriesnotinfluencedbywesternsociety,womenaremorelikelytoprogressthroughthefirststageoflaborinuprightpositionsandmorefreetochangepositionswithoutevidenceofharmtothemselvesortotheirbaby.Positionchangesanduprightposturingarewaysinwhichwomencopewithlaborpain.Giventhefreedomandpermission,manypregnantwomenwillchangepositionssincenopositioniscomfortableforalongtime.Inmanyhealthfacilities,manyprotocolsandproceduresposebarrierstopregnantwomenbeingmobile.TheWorldHealthOrganizationstatesthatawomanshouldhavetheopportunitytoassumeanypositionshewishes,inoroutofbed,duringthecourseoflabor.Sheshouldnotberestrictedtobed,andcertainlynottothesupineposition,butshouldhavethefreedomtoadoptuprightposturessuchassitting,standing,orwalking,withoutinterferencebycaregivers,especiallyduringthefirststageoflabor.19FirstStageofLabor:Inasystematicreviewofrandomizedandquasirandomizedtrialscomparingwomenrandomizedtouprightposition(walking,sitting,standing,kneeling)andrecumbentposition(supine,semi-recumbentandlateral)duringthefirststageoflabor,uprightpositionwasassociatedwith:

● Areductioninthefirststageoflabordurationbyapproximatelyonehourand22minutes(MD-1.36,95%CI-2.22to-0.51;15studies,2503women)

● Reductionincesareandelivery(RR0.71,95%CI0.54to0.94;14studies,2682women)● Lessuseofepidural(RR0.81,95%CI0.66to0.99,ninestudies,2107women)● Onetrialreportedthatbabiesofmotherswhowereuprightwerelesslikelytobeadmittedtotheneonatalintensivecareunit,(RR0.20,95%CI0.04to0.89,200women)20

Inastudyof58womenwhoalternatelyassumedthesittingandsupinepositionsfor15minutesduringcervicaldilatationfrom6to8centimeters,womenexperiencedsignificantlyreducedlowerbackpaininthesittingposition.Thisappliestocontinuouspainaswellaspainwithcontractions.(p<.001)21SecondStageofLabor:

Inasystematicreviewofrandomizedandquasirandomizedcontrolledtrialscomparinguprightorlateralpositionandsupineandlithotomypositionduringthesecondstageoflaborforwomenwithoutepiduralanesthesia,theuprightgroupexperienced:

● areductioninassisteddeliveries[riskratio(RR)0.78;95%CI0.68to0.90;19trials,6024women]

● areductioninepisiotomies[averageRR0.79,95%CI0.70to0.90,12trials,4541women]● fewerabnormalfetalheartratepatterns[RR0.46;95%CI0.22to0.93;twotrials,617

women]● nodifferenceincesareandelivery[RR0.97;95%CI0.59to1.59;13trials,4824women]● non-significantreductioninthedurationofthesecondstage[(MD)-3.71minutes;95%

confidenceinterval(CI)-8.78to1.37minutes;10trials,3485women]● increasedseconddegreeperinealtears[RR1.35;95%CI1.20to1.51,14trials,5367

women]● increasedestimatedbloodlossgreaterthan500ml[RR1.65;95%CI1.32to2.60;13trials,

5158women]22

19

Inwomenwithepiduralanesthesiainthesecondstageoflabor,theuprightgroupexperienced:● Nosignificantdifferenceinoperativebirth(RR0.97;95%CI0.76to1.29;fivetrials,874women)

● Nosignificantdifferenceindurationofthesecondstageoflabor(meandifference-22.98minutes;95%CI-99.09to53.13;twotrials,322women)23

20

AppendixD:Waterimmersion

Anxietyandpainmaytriggerastressresponseleadingtoreduceduterineactivityandlabordystocia.Shoulder-deepwarmwaterimmersionisfoundtoimprovematernalsenseofcontrolandprivacy,lowerratesoflaboraugmentation,epiduralanesthesia,andpossiblyareductioninthefirststageoflabor.Awomanwhofeelsincontrolofherchildbirthexperiencesgreateremotionalwellbeingpostpartum.

Whencomparedtowomenwithimmediateaugmentation(oxytocinandamniotomy),womenwithslowlaborrandomizedtowaterimmersion(≤4hours)experienced:

o greatersatisfactionwithfreedomofmovement(91%v63%)o greaterfeelingofprivacy(96%v81%)o lowerratesofaugmentation(RR0.74,95%CI0.59to0.88,NNT4)o lowerratesofepiduralanesthesia(RR0.71,95%CI0.49to1.01,NNT5)24

(n=99)*Sixneonatesborntowomeninthewaterlaborgroupwereadmittedtotheneonatalunitcomparedwithnoneintheaugmentationgroup(P=0.013).Withtheexceptionofaninfantwithcardiacdefects,alltheseneonates,werereunitedwiththeirmotherswithin48hoursandexperiencednosubsequentproblems.24Reviewof8randomizedcontrolledtrialscomparingwaterimmersionduringfirststageoflaborwithnowaterimmersion:Waterimmersionisassociatedwith:

o ashorterfirststageoflabor(meandifference–32.4minutes;95%CI,from–58.7to–6.13,7trials,n=1461)

o lowerratesofepidural/spinal/paracervicalanesthesia/analgesia(RR0.90;95%CI0.82to0.99,sixtrials,n=2499)

o lowerratesofanyanalgesiause(RR0.72,95%CI0.46to1.12,5trials,n=653)25Therewasnosignificantdifferencein:

o assistedvaginaldeliveries(RR0.86;95%CI0.71to1.05,seventrials,n=2628)o cesareandeliveries(RR1.21;95%CI0.87to1.68,eighttrials,n=2712)o useofoxytocininfusion(RR0.64;95%CI0.32to1.28,fivetrials,n=1125)o perinealtrauma(RR1.16;95%CI0.99to1.35,fivetrials,n=1337)o maternalinfection(RR0.99;95%CI0.50to1.96,fivetrials,n=647),o Apgarscorelessthansevenatfiveminutes(RR1.58;95%CI0.63to3.93,fivetrials,n=1834)o neonatalunitadmissions(RR1.06;95%CI0.71to1.57,threetrials,n=1260)o neonatalinfectionrates(RR2.00;95%CI0.50to7.94,fivetrials,n=1295,6infectionsinimmersion

groups,3infectionsinnon-immersiongroups)25Onelimitationofresearchonwaterimmersionduringlaborthusfaristhelackofstandardizationoflengthoftimeforwaterimmersion.25

21

AppendixE:Amniotomy

Effectsofearlyamniotomyondurationoflaborandratesofcesareandeliveryremainunclear.Accordingtoa2013Cochranereviewof14trialswith8033women,preventativeuseofamniotomyandoxytocinmayormaynotbeassociatedwithareducedrateofcesareandelivery.26ResultsareunclearbecausealthoughtheRRwas0.87,theconfidenceintervalincludedthenulleffect(95%CI0.79to1.01).

Routineearlyamniotomyusedincombinationwithearlyoxytocinwasshowntoshortenthedurationoflabor[averagemeandifference(MD)-1.28hours;95%CI-1.97to-0.59;eighttrials;4816women].Whenusingamniotomytotreatlabordystocia,reviewersstatethat,“theseverityofdelaywhichwassufficienttojustifyinterventionsremainstobedefined”.Reviewerssawnoeffectsonotherindicatorsmeasuredregardingmaternalandneonatalmorbidity.26

22

AppendixF:MembranesSweepingMembranesweepingisthoughttoincreaselocalprostaglandinreleasetostimulatelabor.Itis

performedbyinsertingafingerpasttheinternalosandrotatingittodetachfetalmembranesfromtheloweruterinesegment.

Contraindicationstomembranesweeping:o lowlyingplacentaorplacentapreviao cervicitiso pretermstatus,unlessthepatientisbeinginducedforamedicalindication

Evidence:

Membranesweepinginconjunctionwithinduction:Arandomizedtrialcompared274womenscheduledforinductionattermtomembranesweepingornomembranesweepingattheinitiationofinduction.27Theaimwastodeterminewhethermembranesweepingincreasesthelikelihoodofspontaneousvaginaldelivery.

Results:

Membranesweepingwasassociatedwith:! Higherspontaneousvaginaldeliveryrate(69%vs56%,P=.041)! Shorterinduction-to-deliveryinterval(mean14vs19hours,P=.003)! Fewerrequirementsforoxytocin(46%vs59%,P=.037)! Shorterdurationofoxytocininfusion(mean2.6vs4.3hours,P=.001)27

Preventionofpost-termpregnancies:Asystematicreviewinvolving22trialsand2797women

showedthatthereisreducedfrequencyofpregnancycontinuingbeyond41weeks(RR0.59,95%CI0.46to0.74)and42weeks(RR0.28,95%CI0.15to0.50)whenmembranesaresweptforwomenatterm.Toavoidoneformalinductionoflabor,sweepingofmembranesmustbeperformedineightwomen(NNT=8).Therewasnoevidenceofadifferenceintheriskofmaternalorneonatalinfection.Rateofcesareandeliveryissimilarbetweenthemembranesweepinggroupandthegroupwithoutmembranesweeping(RR0.90,95%CI0.70-1.15).28

23

AppendixG:AcupressureAcupressureisalow-riskinterventionwithmultipledemonstratedbenefitsforlaboringwomen,

includingpainrelief,reducedanxiety,shorterlabors,anddecreasedriskofcesareandelivery.AcupressureisaTraditionalChineseMedicine(TCM)treatmentmodalitythatisthoughttoexertitseffectsby:promotingthecirculationofblood,energyandqi,balancingyinandyang,andpromotingthesecretionofneurotransmitters.29,30

In2011TheCochraneCollaborationconductedareviewofrandomizedclinicaltrialsontheuseofacupunctureandacupressureinlaboringwomen.Thereviewfoundthatwhencomparedtoplacebo,acupressurereducedpainintensity(SMD-0.55,95%CI-0.92to-0.19,onetrial,120women,withacombinedcontrol;SMD-0.42,95%CI-0.65to-0.18,twotrials,322women).29

Seethefollowingdiscussionforevidenceontheeffectsofspecificacupressurepoints,aswellasinstructionsforhowtousethemwithlaboringwomen.San-Yin-Jiao/“SP6”Resultsoftworandomizedclinicaltrialscomparingtheeffectsof30min.ofSP6acupressurecomparedwithSP6touch:

● Reducedpain○ “Thereweresignificantdifferencesbetweenthegroupsinsubjectivelaborpainscoresatall

timepointsfollowingtheintervention:immediatelyaftertheintervention(F=6.646,p0.012);30minutesaftertheintervention(F=5.657,p0.021);and60minutesaftertheintervention(F=6.783,p0.012).”

● Shortenedlabor○ Shortertotallengthoflaborfrom3cmtocompletedilation(n=75,t=-2.864,p=0.006)

● Reducedriskofcesareandelivery(CD)o CDrateforacupressuregroupwas12.8%,SP6touchgroup29.8%,andcontrolgroupwas

22.4%(p=0.049).o CDratesweresignificantlydifferentbetweentheSP6acupressureandnon-SP6

acupressuregroup(p=0.035).31

24

HowToUseSP6:SP6islocated4fingerbreadths(usingpatient’sfingers)abovethetipoftheinnermalleous,justposteriortotheborderofthetibia(seeimagebelow).Duringcontractionsapplybilateraland

simultaneousfirmpressuretoSP6for30min.

LargeIntestine4(LI4)andBladder67(BL67)Resultsofarandomizedclinicaltrial,n=100,withwomenat3-4cmofcervicaldilationandregularuterinecontractionscomparingLI4acupressurewithLI4touch:

● Reducedpainforupto2hours:o Thereweresignificantdifferencesbetweenthegroupsinsubjectivelaborpainscores

immediatelyand20,60,and120minutesafterintervention(P≤.001),usinga10pointpainscale(0meaningnopain,10meaningunbearablepain).

o 20minutespostintervention:acupressuregroup:6.5vscontrolgroup:8.26(pvalue0.001)o 60minutespostintervention:acupressuregroup:7.12vscontrolgroup:8.92(pvalue0.001)o 120minutespostintervention:acupressuregroup:8.57vscontrolgroup:9.83(pvalue

0.001)❧ Shorterfirstandsecondstagelaborduration

o Firststage:acupressuregroup:mean2.44hours,controlgroup:mean3.09hourso SecondStage:acupressuregroup:mean20.51mins,controlgroup:mean28.5mins

• Significantdifferenceinperceptionoflaborpainassessed24hafterbirthusinga10pointpainscale(0meaningnopain,10meaningunbearablepain):

o acupressuregroup:mean6.3,controlgroup:mean8.3,pvalue=0.0001● Greatermaternalsatisfaction

o acupressuregroup:5.76vscontrolgroup:5.3632Resultsofaclinicaltrialrandomizinglaboringwomentooneofthreegroups:LI4andBL67acupressure,lightskinstroking,ornotreatment/conversationonly(n=127):

25

● Decreasedpainduringactivephaseoflabor:Therewasasignificantdifferenceindecreasedlaborpainbetweentheacupressureandcontrolgroups(W=5.607,p=.017).WistheWilcoxonranksumstatistic.

● Noeffectonuterinecontractions30HowToUseLI4:LI4islocatedinthesoftfleshywebbetweenthethumbandforefinger.ApplyfirmpressuretoLI4forthedurationofeachcontraction,over20minutesattheonsetofactivelabor.

26

AppendixH:OcciputPosteriorPositionAtonsetoflabor15-30%offetusesareocciputposterior(OP)inrelationtothematernalpelvis,and

1/3areOPsometimeduringlabor.MostOPfetusesrotateontheirown,leavingonly3-8%beingOPatbirth.Onthewhole,OPpositionisunderdiagnosed.IdentifyingpersistentlyOPfetusesisimportantbecausethepositionisassociatedwith:

○ Increaseinprolongedpregnancy(12%v7%p<.001)oxytocininduction(31%v16%p<.001)andoxytocinaugmentation(52%v32%p<.001)

○ Prolongedlaborlastingmorethan12hours(12%v1.7%p<.001)○ Increaseinoperativevaginalbirth(84%v40%p<.001)33

OPpositionisalsofoundtobeassociatedwithincreasedpostpartumhemorrhageandincreased3rdand4thdegreeperineallacerations.34

NeonataloutcomesassociatedwithOPpositionvsOAposition:

o 5-minuteApgarscorelessthan7(OR1.50,95%CI1.17-1.91)o acidemicumbilicalcordgases(OR2.05,95%CI1.52-2.77)o meconium-stainedamnioticfluid(OR1.29,95%CI1.17-1.42)o birthtrauma(OR1.77,95%CI1.22-2.57)o admissiontotheintensivecarenursery(OR1.57,95%CI1.28-1.92)o longerneonatalstayinthehospital(OR2.69,95%CI2.22-3.25)35

Clinicalsignsofafetusinocciputposteriorpositioninclude:prematureurgetopush,prolonged

labor,andcontractioncoupling.Lowbackpainhasbeenlongthoughttobeassociatedwiththeocciputposteriorposition,butthisfeaturemayormaynotbepresentandisnotbeareliableindicatorofOP.

UltrasoundisthemostaccuratemethodfordiagnosingOPposition.Transabdominalultrasoundis

reasonablyaccuratewithanerrorrateof6-8%,butcanbedifficultifthefetalheadisdeeplyengaged.Transperinealultrasoundlikelyhashighestaccuracy,butismoreintrusive.Thismethodinvolvesplacingthetransducertransverseonthevulvamidwaybetweentheperineumandclitoris.36

27

AppendixI:ManualRotationManualrotationisasafeandeffectiveoptionforcorrectingpersistentocciputposteriorposition

(OP).73%ofattemptsresultinasuccessfulrotation.34AnRCTof731womenwhohadmanualrotation(MR)comparedto3000whodidnotundergoMRshowedMRtobeassociatedwiththefollowingoutcomes.

● Comparedtoexpectantmanagement,womenwithmanualrotationwerelesslikelytohave:○ cesareandelivery[(aOR)0.12;95%CI(0.09-0.16)],○ severeperineallaceration[aOR0.64;95%CI(0.47-0.88)],○ postpartumhemorrhage[aOR0.75;95%CI(0.62-0.98)],○ chorioamnionitis[aOR0.68;(0.50-0.92)].○ ThenumberofrotationsattemptedtoavertoneCDwas4.34

Risks:Womenwhohadatrialofrotationhadanincreasedriskofcervicallaceration[aOR2.46;(1.1-5.4)].

*aOR:adjustedoddsratio

Tipsformanualrotation:● Thereisnodatatoguidehowtodoit,orwhentodoit.● Ifvertexis+3stationitisverydifficult.0to+1stationisbetter● Cervicaldilationof7cmormoreisthoughttobeideal● Membranesmustberuptured● UseultrasoundtoconfirmOPpositionandtolocatethefetalspinetoguidethedirectionofyour

rotationofthefetalhead.● Needforanesthesiaisveryindividual.Manywomentolerateitwellwithoutanesthesia

*Documentinformedverbalconsentandincludethefollowing:● Risksoftheprocedure:cervicallacerationandcordprolapse(ifdonevigorouslyorifthereisalarge

de-stationofthefetalhead).Procedureisnotassociatedwithfetaldistress.● Theproceduremaybeuncomfortable,andanesthesiaisoptional.● Procedureishighlysuccessful(73%),butfailureisapossibility.

Twoproposedmethodsformanualrotation

1.Spreadfingersoverposteriorparietalbone,cradleheadwithfingers(maybethumbontopsideofhead),slightlylifttheheadupward(“de-stationthehead”)androtatetheheadjustbeforeacontraction.Holditthereduringacontractionwhilemompushestofixitintothenewposition.Bestusedifcervixisgreaterthan7-8cmdilated.2.Twofingersonsagittalsuture,“likefingertippull-upinrockclimbing”.Thisisbestforwhenthecervixisnotcompletelydilated,orthereisaconcernaboutcervicallaceration.

28

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