guidelines for maternity providers offering … guidelines for maternity providers offering...

Guidelines for maternity providers offering antenatal screening for Down syndrome and other conditions in New Zealand

November 2009

2 Guidelines for maternity providers offering antenatal screening for Down syndrome and other conditions in New Zealand

Antenatal and newborn screening The National Screening Unit (NSU) of the Ministry of Health is responsible for the development, implementation and management of three antenatal and newborn screening programmes: • UniversalOfferAntenatalHIVScreeningProgramme • NewbornMetabolicScreeningProgramme • UniversalNewbornHearingScreeningandEarlyInterventionProgramme.

The NSU is also responsible for the introduction of quality improvements to antenatal screeningforDownsyndromeandotherconditions. Screening for various conditions is a significant aspect of contemporary antenatal care and many of the procedures carried out during routine antenatal appointments are used asscreeningtools.Takingawoman’sbloodpressureandreviewingaurinalysisareusedtoscreenforpre-eclampsia,diabetes,orurinaryinfection.Abdominalpalpationisused to screen for babies who are small for their gestational age, and pregnancies with polyhydramnios.BloodistestedtoscreenforhepatitisB,HIV,andrhesusantibodies.

The quality improvements to antenatal screening for Down syndrome and other conditions have been introduced to bring screening in New Zealand into line with international best practice, and to provide pregnant women and their families/whānau with information with whichtomakechoicesaboutthecareandmanagementoftheirpregnancy.

AcknowledgementsTheseGuidelineshavebeenproducedinconsultationwithaTechnicalWorkingGroup. TheNationalScreeningUnitwouldliketothankthemanyindividualsandgroupswhocontributedtothedevelopmentofthefinalversionofthisdocument.


PublishedinNovember2009bytheNationalScreeningUnit POBox5013,Wellington,NewZealand

ISBN:978-0-478-33931-4 (print) ISBN:978-0-478-33932-1 (online)

HP4965

ThisdocumentisavailableontheNationalScreeningUnitwebsite:www.nsu.govt.nz

3Guidelines for maternity providers offering antenatal screening for Down syndrome and other conditions in New Zealand

CONTENTSAntenatalandnewbornscreening 2

Acknowledgements 2

List of acronyms 4

Definitions 4

1 INTRODUCTION 5

2 BACKGROUNDINFORMATION 62.1 QualityimprovementstoantenatalscreeningforDownsyndromeand other conditions 62.2 ImprovingequityofaccesstoantenatalscreeningforDownsyndrome and other conditions 72.3 ConditionsscreenedforbyantenatalscreeningforDownsyndrome and other conditions 82.4 Downsyndrome 8 2.4.1 CommonhealthissuesassociatedwithDownsyndrome 9

2.5 Potentialbenefitsandharmsofantenatalscreeningfor Down syndrome and other conditions 9

3 THEPRACTICALITIES 113.1 Thescreeningpathways 113.2 Timingofscreeningtests 133.3 Informedconsent 143.4 Documentation 153.5 Communication 163.6 Provisionofinformation 163.7 Initialdiscussion 183.8 Offerofscreening 20 3.8.1 Firsttrimestercombinedscreening 21 3.8.2 Secondtrimestermaternalserumscreening 21 3.8.3 Referringwomenforscreening 22

3.9 Laboratoryprocesses 23 3.9.1 Laboratoryresponsibilities 24 3.9.2 Exceptions 25

3.10 Results 26 3.10.1 Increasedriskresults 28

3.11 Geneticcounsellingandotherreferrals 293.12 Fundingofdiagnostictesting 303.13 Datacollection,monitoringandreporting 30

APPENDIXONE:GLOSSARYOFTERMS 31

APPENDIXTWO:RESOURCESANDCONTACTS 33

APPENDIXTHREE:BIBLIOGRAPHY 35


List of acronymsAFP Alpha-fetoprotein(abiochemicalmarker)ßhCG Beta-humanchorionicgonadatrophin(abiochemicalmarker)BPD BiparietaldiameterCRL Crown–rumplengthCVS ChorionicvillussamplingDHB DistrictHealthBoardEDD EstimatedDateofDeliveryIVF InvitrofertilisationLMC LeadMaternityCarerLMP LastMenstrualPeriodNSU National Screening Unit of the Ministry of HealthMoM Multiple of the MedianNT Nuchaltranslucency(anultrasoundmarker)PAPP-A Pregnancy-associatedplasmaproteinA(abiochemicalmarker)µE3 Unconjugatedoestriol(abiochemicalmarker)

DefinitionsIntheseGuidelines‘maternityprovider’and‘primarymaternityservices’havethesamemeaningasinthePrimaryMaternityServicesNotice2007.

Maternity provider means an organisation or an individual that provides primary maternity services.

Primarymaternityservicesmeans: • leadmaternitycare • maternitynon-LMCservices • specialistmedicalmaternityservices.


1 INTRODUCTIONThe purpose of these Guidelines is to identify best practice for maternity providers offering antenatalscreeningforDownsyndromeandotherconditionsinNewZealand.TheGuidelinesare intended as a resource to inform practice and support maternity providers to improve the qualityofscreening.

The Guidelines promote women-centred care, and involve the co-ordination of activities of a rangeofmaternityproviders.AcentralconceptofantenatalscreeningforDownsyndromeandother conditions is unconditional acceptance of and support for choices made by women about screening.

MaternityprovidershaveacontractualobligationunderthePrimaryMaternityServicesNotice2007,issuedpursuanttosection88oftheNewZealandPublicHealthandDisabilityAct2000,to provide services within screening initiatives endorsed by the Ministry of Health, including antenatalscreeningforDownsyndromeandotherconditions.

Maternity providers are responsible for: (a) providing information and education about screening (b) offering referrals for screening tests (c) communicating screening results (d) offering specialist referrals (e) ensuring compliance with the: • PrivacyAct1993andHealthInformationPrivacyCode1994 • NewZealandPublicHealthandDisabilityAct2000 • CodeofHealthandDisabilityServicesConsumers’Rights1996 • HealthAct1956 • HealthPractitionersCompetenceAssuranceAct2003 • PublicRecordsAct2005.

TheseGuidelinesshouldbereadinconjunctionwithlocalDistrictHealthBoard(DHB)policiesandguidelines.


2 BACKGROUND INFORMATION AntenatalscreeningforDownsyndromeandotherconditionshasbeenavailabletopregnantwomeninNewZealandsince1968.InrecentyearsconcernhasbeenexpressedaboutthequalityandsafetyofpracticeforantenatalscreeningforDownsyndromeandotherconditions.Mountingevidencehassupportedsaferandhigher-qualitypractice.In2006,ProfessorPeterStone identified that current practice for antenatal screening for Down syndrome and other conditions was “ad hoc, based mostly on ultrasound scanning or maternal age alone, and did notreflectinternationalbestpractice”.1

Somemembersofthe2007AntenatalDownSyndromeScreeningAdvisoryGroupdebatedwhetheritwasappropriatetoscreenforDownsyndromeandotherconditionsatall.However,there was agreement that the status quo could not be continued when New Zealand practice wasinconsistentwithinternationalunderstanding,technologyandpractice.InOctober2007CabinetagreedtoqualityimprovementstoantenatalscreeningforDownsyndromeandotherconditions.

The quality improvements to antenatal screening for Down syndrome and other conditions are to improve the quality and safety of screening services for pregnant women in New Zealand who choosetohavescreening.Theseserviceswillbeconsistentwithinternationalpractice.

2.1 Quality improvements to antenatal screening for Down syndrome and other conditionsAntenatalscreeningforDownsyndromeandotherconditionsisawayofassessingthelikelihoodthatafetushasDownsyndromeoranotherspecificcondition.Screeningisnotdiagnostic,anddoesnotdetectwithcertaintyifaconditionispresent.Screeningdivideswomenintotwogroups:apositiveresultmeansthereisanincreasedriskofaparticularconditionbeingpresent,whileanegativeresultmeansthereisalowrisk.2Womenwithanincreasedriskresultmayormaynotchoosetogoontodiagnostictesting.

Screening for Down syndrome and other conditions involves a sequence of events referred to asthe‘screeningpathway’.Theaimistoofferwomeninformationandchoiceinthecareandmanagementoftheirpregnancy.

QualityimprovementmeasuresforantenatalscreeningforDownsyndromeandotherconditionsinclude: (a) First trimester combined screening, which combines the results of a first trimester maternal serum test with a nuchal translucency (NT) scan result3 and other parameters suchascrown–rumplength,maternalageandweight,andgestationtogiveasingle firsttrimesterriskresult.Thiscombinedresultprovidesasignificantlybetterrisk assessmentthanNTscanninginisolation.

1StoneP,AustinD.2006.Report to the National Screening Unit: Assessment of prenatal screening for Down syndrome in New Zealand.Auckland:UniServicesLimited.2NSU.2007.Antenatal Down syndrome Screening Advisory Group Report, January 2007. Wellington:MinistryofHealth.3Althoughthefirsttrimestermaternalserumscreeningispubliclyfunded,thewomanisoftenrequiredtomakeaco-paymentfortheNTscancomponentoffirsttrimestercombinedscreening.


(b) Second trimester maternal serum screening, which involves the addition of a fourth markertotheexistingsecondtrimestermaternalserumscreening(‘tripletest’).The results of the serum tests are incorporated with other parameters such as maternal age and weight,andgestation,togiveasinglesecondtrimesterriskresult.(c) Recommendations for practice, including the discontinuation of the use of maternal age andNTscanningasscreeningtoolsinisolation.(d) Consumer resources.(e) Education and trainingforproviders.

The goals of the implementation of quality improvements to antenatal screening for Down syndrome and other conditions are to: • improveequityofaccesstoscreening • supportwomentomakeaninformedchoiceaboutwhetherornottoparticipate in screening • improvethesensitivityandspecificityratesofavailablescreeningoptions • ensurematernityprovidersareappropriatelyeducatedaboutantenatalscreeningfor Downsyndromeandotherconditions.

Desired outcomes of the quality improvements include: • improveddetectionratesandreducedfalsepositiveratesinscreeningforDown syndrome and other conditions • voluntaryparticipationateachstepofthescreeningpathway • unconditionalsupportforthechoicesmadebywomenthroughouttheirpregnancy • theprovisionofaccurateandnon-directionalinformation(bothmedicalandnon-medical) tosupportwomenintheirdecision-making • theactiveinvolvementandsupportoffamily/whānau(ifthewomanwishes).

2.2 Improving equity of access to antenatal screening for Down syndrome and other conditionsImprovingequityofaccessisakeygoalofthequalityimprovementsforantenatalscreeningforDownsyndromeandotherconditions.DataindicatethatMāoriandPacificwomenarelesslikelytoaccessearlyantenatalcarethannon-Māori,andthatbarrierstoaccessingaspectsofantenatal care may be faced by new migrants and women from rural and lower socioeconomic environments.4

Lackofknowledge,transport,traveltimeandchildcarehaveallbeenidentifiedaspotentialbarriers to accessing screening, and women in rural areas may have difficulty accessing ultrasoundandamniocentesisservices.5

The quality improvements for antenatal screening for Down syndrome and other conditions aim to improve equity by providing two access points to screening, one in the first and one in the

4MinistryofHealth.2007.Report on Maternity: Maternal and Newborn Information 2004.Wellington:MinistryofHealth.5ToiteTaiao:theBioethicsCouncil.2008.Who Gets Born? A report on the cultural, ethical and spiritual aspects of pre-birth testing by Toi te Taiao: the Bioethics Council.URL:http://www.bioethics.org.nzPublicationNumber:BC19.


secondtrimester.Theoptionofscreeningduringthesecondtrimestermeansscreeningcanbeofferedtowomenwhodonotaccessmaternitycareearlyintheirpregnancy.

The maternal serum screening component of first trimester combined screening is publicly funded.Womenareusuallyrequiredtomakeaco-paymentfortheNTscan.Secondtrimestermaternalserumscreeningisfullypubliclyfunded.

Womenmayonlyaccessonepubliclyfundedscreeningoption.However,secondtrimestermaternal serum screening is funded for women who accepted but did not complete first trimestercombinedscreening.

2.3 Conditions screened for by antenatal screening for Down syndrome and other conditionsAntenatalscreeningforDownsyndromeandotherconditionsmayindicateanincreasedriskforDownsyndrome(Trisomy21),Trisomy18(Edwardssyndrome),Trisomy13(Patausyndrome),neuraltubedefects(eg,spinabifida)andotherraremetabolicorgeneticdisorders.

Inaddition,ultrasoundscansundertakenaspartofscreeningmaydetectsomemajorfetalstructuralanomalies,suchasskeletalanomalies,brainandneuraltubedefects,congenitalheartdefects,andabnormalitiesoftherenaltract,gastrointestinalsystem,andabdominalwall.

2.4 Down syndromeDownsyndromeoccursinapproximately1in700births(approximately90babieseachyearinNewZealand).Two-thirdsofbabieswithDownsyndromeareborntowomenundertheageof35,duetothehigherbirthrateinthisagegroup.6

Downsyndromeiscausedbyanextracopyofchromosome21insideeachofthebody’scells.The chromosomes are located in the nucleus of each cell, and contain the genetic material that, incombinationwithenvironmentalinfluences,determinesaperson’sindividualcharacteristics.InDownsyndrome,insteadofapairtherearethreecopiesofchromosome21.TheextrageneticmaterialfromtheextrachromosomegivesthecharacteristicsofDownsyndrome.

TheNewZealandDownSyndromeAssociationadvisesthat:People with Down syndrome are all unique individuals and vary in their abilities and achievements. They do have features in common, but they also closely resemble their parents and family. Many characteristics are associated with Down syndrome, but any one person will only have some of them. Thus each person is an individual, with a unique appearance, personality and set of abilities. The extent to which a child shows the physical characteristics of the syndrome is no indication of his or her abilities and achievements.7

PeoplewithDownsyndromehavevaryingdegreesofdisability.TheNewZealandDisabilityStrategy states that:

Disability has a lot to do with discrimination, and has a lot in common with other attitudes and behaviours such as racism and sexism that are not acceptable in our society. Disability is also closely linked to ideas about the human rights of people with impairments. Without human rights we cannot live as full human beings.8

6RosenT,D’AltonME.2005.DownSyndromescreeninginthefirstandsecondtrimesters:whatdothedatashow?Seminars in Perinatology29:367–75.7NZDSA:www.nzdsa.org.nz,retrieved09September20098MinisterforDisabilityIssues.2001.New Zealand Disability Strategy. Wellington:MinistryofHealth.


TheaveragelifeexpectancyofpeoplewithDownsyndromehasincreasedwithimprovedhealthcare, better education, greater opportunities and a shift in societal attitudes during the past20to30years.StudiesindicatethataveragelifeexpectancyintheUKwasestimatedtobe9yearsofagein1929and12yearsin1949.Subsequentreportshaveshownamarkedincreaseinlifeexpectancythatbeganinthe1950s.Bytheyear2000themedianlifeexpectancyforpeoplewithDownsyndromeinAustraliawas60years.9,10

2.4.1 Common health issues associated with Down syndrome PeoplewithDownsyndromeexperiencevaryingdegreesofdelayintheirlearninganddevelopment,andmayhaveadditionalhealthneeds.SomeofthehealthissuesassociatedwithDown syndrome include: • hearinglossinupto50percentofpeoplewithDownsyndrome • congenitalheartdiseaseinupto50percent • thyroiddisorders,mostcommonlyhypothyroidism,inupto40percent • gastrointestinaltractcongenitalmalformations,suchasduodenalatresiaand Hirschsprung’sdisease • cataractsandvisualrefractiveerrors • childhoodleukaemiainabout2percent • earlyonsetAlzheimer’sdisease.

2.5 Potential benefits and harms of antenatal screening for Down syndrome and other conditionsScreening poses different ethical considerations from those that arise when a person presents formedicalcarebecausetheyareunwell.Maternityprovidershaveaspecialdutyofcarewhenreferringhealthyasymptomaticwomenforscreening.Allpregnantwomenmustbegivenfullinformation regarding antenatal screening for Down syndrome and other conditions, including therisks,benefitsandharmsofscreening,sothattheymaymakeinformedchoices.

AntenatalscreeningforDownsyndromeandotherconditionshascomplexethicalandsocialimplications,aswellastechnicalconsiderations.Technicalconsiderationsinvolveatrade-off between the sensitivity (detection rate) and the specificity (false positive rate) of thescreeningtests.Avalid,reliableandsafescreeningtestisatthecoreofanyorganisedpopulation-basedscreeninginitiative.InthecontextofantenatalscreeningforDownsyndromeand other conditions, it has been identified that combining ultrasound and maternal serum markersincreasesdetectionrates(improvessensitivity)and/orreducesthenumberofwomenconsideredtobeatincreasedrisk(improvesspecificity).

The potential benefits of antenatal screening for Down syndrome and other conditions include: • accesstoinformationthatmayprovidemorechoiceinthecareandmanagementof a pregnancy • alowriskresultmeansababyisunlikelytohaveDownsyndromeoranother conditionscreenedfor.

9YangQ,RasmussenSA,FriedmanJM.2002.MortalityassociatedwithDown'ssyndromeintheUSAfrom1983to1997:apopulation-basedstudy.Lancet359:1019–2510BittlesAH,GlassonEJ.2004.Clinical,social,andethicalimplicationsofchanginglifeexpectancyinDownsyndrome.Dev.Med.Ch.Neurol.


The potential harms of antenatal screening for Down syndrome and other conditions include that: • anincreasedriskresultmayturnouttobeafalsepositiveresult • alowriskresultmayleadawomantobelieveherbabywillnothaveDown syndrome or another condition screened for, when the baby does have a condition • anincreasedriskresultmayleadtoadecisiontohaveadiagnostictestthathasan inherentriskofiatrogenicmiscarriage.

While the purpose of these quality improvements is to offer women information and choice, there may be a perception that they will lead to more terminations of pregnancy and, ultimately,fewerpeoplewithDownsyndromeinsociety.Thisisnottheintentionofthequalityimprovements for antenatal screening for Down syndrome and other conditions, which aim to improvecurrentscreeningpractice.


3 THE PRACTICALITIES

3.1 The screening pathways

SECOND TRIMESTER MATERNAL SERUM SCREENING

Provision of information about screening

Section 3.6

FIRST TRIMESTER COMBINED SCREENING

InitialdiscussionSection 3.7

First trimester combined screening

(2 maternal serum markers)

Section 3.8.1

Offer of screening Section 3.8

End of screening process

Screeningdeclined

First trimester com

bined screening 9 weeks to 13 w

eeks 6 daysSecond trim

ester maternal serum

screening 14 weeks to 20 w

eeks

Increased riskSection 3.10.1

Results to maternity provider

Section 3.10

Offer of screening Section 3.8

End of screening process

Screeningdeclined

Increased riskSection 3.10.1

Results to maternity provider

Section 3.10

Screeningaccepted

Low riskSection 3.10

Second trimester maternal serum

screening

(4 maternal serum markers)

Section 3.8.2

OR

Offer of specialist referralSection 3.10.1

Offer of specialist referralSection 3.10.1

Screeningaccepted

Low riskSection 3.10

InitialdiscussionSection 3.7

Provision of information about screening

Section 3.6


The Ministry of Health recommends that all pregnant women are offered antenatal screening forDownsyndromeandotherconditionsineitherthefirstorsecondtrimesterofpregnancy.Theexceptioniswomenwhohavepreviouslybeenpregnantwithorhavehadachildwithasignificantphysicalorlearningdisability,orhaveafamilyhistoryofageneticcondition.Thesewomenhaveadifferentriskstatus.Screeningmaystillbeagoodoptionforthem,butbefore screening is offered they should be offered a referral for a discussion with a specialist obstetricianorgeneticisttoclarifytheiroptionsandtheappropriatenessofscreening.

Screeningisnotcompulsory,soallpregnantwomenneedtodecideiftheywanttoparticipate.Womenwhodecidenottoparticipateinscreeningmaydosoformanyreasons.Forexample,theymayperceivethattheyareatlittleorlowrisk,orbeuncomfortablewiththeconceptofscreening.Theirreasonsaretheirownandtheirdecisionmustberespected.

First trimester combined screening to be offered to all

women who present early in pregnancy

OR

Second trimester maternal serum screening to be

offered to all women who present later in

pregnancy

AND

Recommendations for practice

• Bloodtestthat measures two maternal serum markers(PAPP-A andßhCG)combined with NT scan results

• Availabletoall women who present in the first trimester

• Thebloodtest is fully funded

• Womenareusually requiredtomakea co-payment for the NT scan

• Bloodtestthat measures four maternal serummarkers (ßhCG,AFP,µE3 andinhibinA)

• Availabletowomen who present after the first trimester or who do not access first trimester combined screening

• Thebloodtestis fully funded

• Thediscontinuation of the use of maternal age and nuchal translucency as screening tools in isolation

Provision of accurate and non-directive information (both medical and non-medical)

Unconditional support for decisions made by women throughout pregnancy, including the decision as to whether or not to participate in screening

Support if women want family/whanau to be actively involved-


3.2 Timing of screening testsThe following diagram shows when the different antenatal screening tests for Down syndrome andotherconditionsmaybeundertaken.Thetimingofscreeningrelativetothewoman’sgestationmaybeimportantinrelationtothechoicesavailabletoher.

First trimester combined screening 9 weeks to 13 weeks 6 days

Second trimester maternal serum screening 14 weeks to 20 weeks

9W 10W 11W 12W 13W 6D

NT 11W to 13W 6D

Blood collected 9W to 13W 6D

Optimal timing NT11½ - 13½ weeks

14W 15W 16W 17W 18W 19W 20W

Blood collected 14W to 20W

Optimal timing fourmaternal serum markers

(ßhCG, AFP, µE3 and inhibin A) 14 - 18 weeksOptimal timing two

maternal serum markers

(PAPP-A and ßhCG) 10 - 12 weeks


Guidelines InformationPARTICIPATION IN SCREENINGMaternity providers must establish whether the womanwishestoparticipateinscreeningornot.

While screening is to be routinely offered, participation in screening is not to be regarded as routine.Allwomenshouldbeofferedthechoiceto participate in screening, fully informed of the decisionsandoptionsthatareinvolved.

The right to decline screening must be made clear and any such decision, including withdrawal of consent,mustberespected.

PRINCIPLES OF INFORMED CONSENTMaternity providers must apply the principles of informedconsent.

The woman must have a clear understanding of the decisionsshemayneedtomakeateachstepinthescreeningpathway.

Informedconsentmayincludetheuseofinterpreters and culturally appropriate counselling andsupportservices.

3.3 Informed consentAnappropriateinformedconsentprocessiskeytoofferingscreeninginawaythatissociallyandethicallyresponsible.Informedconsentmustbeintegratedthroughoutthescreeningpathway and include consent that anonymised information can be used for monitoring and reporting.

TheCodeofHealthandDisabilityServicesConsumers’RightsprovidesthatNewZealandhealthcare consumers have a legal right to appropriate information to enable them to give informed consent.InformationabouttheCodecanbeviewedonthewebsiteoftheHealthandDisabilityCommissioner(www.hdc.org.nz).

There is anecdotal evidence that some pregnant women have had antenatal screening for Down syndrome and other conditions without understanding the nature and implications of the screening.ThequalityimprovementsforantenatalscreeningforDownsyndromeandotherconditions will reduce the potential for screening to occur without women having given informed consent,byincreasingknowledgeandunderstandingamongmaternityproviders,andbyprovidingappropriateconsumerinformationforwomen.

Maternity providers should be cognisant of the important implications for pregnant women and theirfamilies/whānauwheneveranyaspectofscreeningisdiscussed.


3.4 Documentation Written consent for antenatal screening for Down syndrome and other conditions is not required bytheCodeofHealthandDisabilityServicesConsumers’Rights,iftheprocessandconsentdecisionsareclearlydocumentedinthewoman’snotes.

Guidelines InformationDOCUMENTATION OF PROCESS AND DECISIONSMaternity providers must document information abouttheprocessandthewoman’sdecisionsateachstepofthescreeningpathway,inthewoman’snotes.

Maternity providers should document information about: • theinitialdiscussion/s • whenandhowtheopportunitytoask questions was provided • whetheranyfurtherinformationwas requested and/or issues raised, and the information provided and/or how the issues were addressed • whetherinterpretersorotherserviceswere used • whetherthewomanconsentedtoor declined screening • ifthewomanconsentedtoscreening, then that she consented to have her anonymised information included in monitoringandreporting.

DOCUMENTATION OF ALL RESULTSMaternity providers must document all results receivedfromthelaboratoryinthewoman’snotes.

Maternity providers must document that results havebeengiventothewoman.

Ifawomanhasindicatedthatsheonlywantsto receive some of the results, this must be documented and the results that were given must beclearlyidentified.

Maternity providers may also document details of when, where, and how results were given to the woman(andherfamily/whānau).

DOCUMENTATION OF INCREASED RISK RESULTSMaternityprovidersmustdocumentthewoman’sdecisionsfollowinganincreasedriskresultinhernotes.

Maternity providers must document the consent processwhenofferingspecialistobstetricreferral.

Maternity providers must document decisions that weretakeninrelationtoresultsandanyfollow-upactions.

Whereascreeningresultis‘increasedrisk’,thewoman’snotesshoulddocumentthataninformedconsent process was followed for the offer of referraltoaspecialistobstetrician.Thismayinclude: • thatinformationaboutreferraltoa specialist obstetrician was given • whethertheofferwasacceptedordeclined • ifaccepted,thedatethespecialistobstetric referral was made, and the outcome of the referral • ifdeclined,anydetailsaboutthedecline • othersupport,resourcesandinformation thatweremadeavailable.


3.5 CommunicationThematernityproviderreferringthewomanforscreeningisresponsibleforexplainingthepurpose of antenatal screening for Down syndrome and other conditions, including the potential benefitsandharms,andforreceivingandfollowinguptheresults.Maternityprovidersshouldnotallowscreeningtounderminetheconceptofpregnancyasapositiveexperience.

Womenneedtoknowwhatconditionsscreeningmightindicateaswellastheimplicationsoflowriskandincreasedriskresults.

3.6 Provision of information Provisionofinformationthroughoutthescreeningprocessisintegraltoinformedconsent.Informationshouldbetailoredtosuittheneedsofeachwomanthroughoutthescreeningprocess.

Guidelines InformationAPPROPRIATE PROVISION OF INFORMATION Maternity providers must provide accurate and non-directional information about antenatal screening for Down syndrome and other conditions toallpregnantwomen.

Maternity providers must provide each pregnant woman with information about screening in a manner that enables her to understand the nature andimplicationsofscreening.

Womenshouldhavesufficienttimetoaskquestions, consult others and fully consider their choicesateachstepinthescreeningpathway.

Ministry of Health consumer resources have been developedtofacilitatediscussionsaboutscreening.Theseresourcesshouldbeofferedtoallwomen.

Onlineeducationmodulesandotherresources are available for maternity providers via www.nsu.govt.nz.


WAYS OF PROVIDING INFORMATIONMaternity providers should provide information about antenatal screening for Down syndrome and otherconditionsinavarietyofways.

Informationshouldbeprovidedindifferentways,including: • discussionsaboutantenatalscreeningfor Down syndrome and other conditions • writtenresources • referraltoothersourcesofinformation, such as specialist organisations and their websites • withtheassistanceofaninterpreterif necessary • withfamily/whānaupresent(ifthewoman wishes).

Informationshouldbecommunicatedwithregardto the different levels of understanding and backgroundknowledgethatwomenbringtotheprocess.

FAMILY HISTORYMaternity providers must offer to refer women who have previously been pregnant with or have had a child with a significant physical or learning disability, or a family history of a genetic disorder, for a discussion with a specialist obstetrician or geneticistbeforeofferingscreening.

Maternityprovidersshouldexerciseparticularsensitivity and be aware that these women may have already given careful thought to having or not havingscreening.

TAILORING COMMUNICATION TO THE INDIVIDUALMaternityprovidersshouldtakeintoaccountthatthewoman’ssocioculturalenvironmentmayimpactonthewaythemessageiscommunicated.

Maternity providers should consider and discuss thewoman’sindividualcircumstancestoenableandsupportinformeddecision-making.Thismayinvolvemorethanonediscussion.


3.7 Initial discussionAdiscussionintroducingantenatalscreeningforDownsyndromeandotherconditions should be initiated by the maternity provider as early as possible in the pregnancy,toallowwomentheopportunitytoconsiderparticipationinscreening,askquestions,andseekfurtherinformation.

The discussion should include:(a) That the purpose of screening is to provide pregnant women and their families/whānauwithinformationwithwhichtomakechoices.

(b) The screening options available are first trimester combined screening or secondtrimestermaternalserumscreening.

(c) The nature of screening, and the importance of timing: Firsttrimestercombinedscreening: • Combinesafirsttrimesterbloodtestresultwithanuchaltranslucency scan measurement, and incorporates age, weight, gestation, and other information (as requested on the referral form) to give one result • Bloodtestcanbetakenbetween9weeksand13weeks6days,andthe optimaltimingis10to12weeks • NTscancanbeundertakenbetween11weeksand13weeks6days • Aco-paymentfortheNTscanisusuallyrequired.

OR

Second trimester maternal serum screening: • Incorporatesasecondtrimesterbloodtestresultwithage,weight, gestation, and other information to give one result • Bloodtestcanbetakenbetween14weeksand20weeks, andtheoptimaltimingis14to18weeks.

(d) The conditions screened for: • Downsyndrome(Trisomy21) • Trisomy18(Edwardssyndrome) • Trisomy13(Patausyndrome) • Neuraltubedefects • Someraremetabolicandgeneticdisorders.

Inaddition,ultrasoundscanscanshowmajorfetalstructuralanomalies, suchasskeletalanomalies,brainandneuraltubedefects,congenital heart defects, and abnormalities of the renal tract, gastrointestinal system andabdominalwall.

(e) That screening is voluntary and the woman has the right to change her mindatanytime.


(f) The choices available to women: • Whetherornottoparticipateinscreening • Involvingfamily/whānaumembersinthedecision-makingprocess • Receivingselectedscreeningresultsonly.

(g) The limitations of screening: • Screeningisnotdiagnosticanddoesnotidentifyallbabieswhohavea condition • Screeningdoesnotcovereverydisorder • Screeningcangivefalsepositiveandfalsenegativeresults.

(h) What screening results might mean: • Thereisalowriskthatthebabyhasoneoftheconditionsscreenedfor • Thereisanincreasedriskthatthebabyhasoneoftheconditions screened for • Thatthewomanmayneedtodecidewhethertoproceedtodiagnostic testing.

(i) What the woman might do if screening indicates her baby has an increased riskofDownsyndromeoranothercondition: • Acceptareferraltoaspecialistobstetriciantodiscussheroptions • Decidenottoacceptareferraltoaspecialistobstetrician.

(j) The diagnostic testing options available to the woman in the region, and the risksinherentinthese.

(k) Thepotentialbenefitsofscreening: • Accesstoinformationthatmayprovidemorechoiceinthecareand management of a pregnancy • AlowriskresultmeansababyisunlikelytohaveDownsyndromeor anotherconditionscreenedfor.

(l) The potential harms of screening: • Anincreasedriskresultmayturnouttobeafalsepositiveresult • Alowriskresultmayleadawomantobelieveherbabydoesnot have Down syndrome or another condition screened for when the baby does have a condition • Anincreasedriskresultmayleadtoadecisiontohaveadiagnostictest whichhasaninherentriskofiatrogenicmiscarriage.

(m) Where further information, resources, and support are available, including contact details and availability of support groups, counsellors andculturaladvisors.

(n) Informationaboutdatacollection,monitoring,andreporting,including thatthewoman’sanonymisedinformationwillbeusedformonitoring andreporting.


3.8 Offer of screening When offering antenatal screening for Down syndrome and other conditions, maternity providers must ensure that women have been given information that allows them to be aware of the limitationsanduncertaintiesofscreening,andinparticulartheriskoffalsepositiveandfalsenegativeresults.

Guidelines InformationOFFERING ACCESS TO SCREENINGMaternity providers must offer women access to first trimester combined screening or second trimestermaternalserumscreening.

Maternity providers must ensure that women are not made to feel that they must accept screening aspartoftheirantenatalcare.

Allpregnantwomenshouldbeofferedaccessto first trimester combined screening, unless some components of first trimester combined screening are not available in their area, or they have presented later in pregnancy, in which case they should be offered second trimester maternal serumscreening.

Women should understand that only one screening optionwillbepubliclyfundedineachpregnancy.

ENSURING INFORMATION HAS BEEN PROVIDED AND DISCUSSEDMaternityprovidersmustnotmakeanofferofscreening without first providing women with information and engaging in a discussion about screening.

Provisionofinformationaboutscreening↓Initialdiscussion↓Offerofscreening

The offer should not be made until women have been given all the information listed under the ‘Provisionofinformation’and‘Initialdiscussion’sectionsintheseGuidelines.

Some women may wish to discuss their options withfamily/whānau.

The overriding principle is the maintenance of the conceptofpregnancyasapositiveexperience.Women are free to decline screening and must be given ongoing unconditional support, regardless of thechoicestheymakeduringtheirpregnancy.

OTHER CONDITIONS SCREENED FOR Maternity providers must discuss the other conditions that may be indicated as a result of participation in antenatal screening for Down syndromeandotherconditions.

The woman may decide that there are some results thatshedoesnotwanttobetold.Forexample,a woman may decide that she wants results that showanincreasedriskofTrisomy13and18(whichmay be incompatible with life), but not results thatshowanincreasedriskforDownsyndrome.However, women should also be advised that it may not be possible to give individual results for specific conditions, as results may indicate an increasedriskformorethanonecondition.


Guidelines InformationFIRST TRIMESTER COMBINED SCREENING COMPONENTS AND TIMEFRAMESMaternity providers must advise women where they can go for their blood test and NT scan and when theymusthaveeachofthesetests.

Forfirsttrimestercombinedscreening,maternityprovidersmustensurethewomanknowstherearetwo components, blood test and NT, and she needs tohaveeachwithincertaintimeframes.

Firsttrimestermaternalserumscreeningtimingis9weeksto13weeks6days,andtheoptimalsensitivityis10–12weeks.

TheNTscancanbeundertakenbetween11weeksand13weeks6days,andthewomanisusuallyrequiredtomakeaco-paymentfortheNTscan.

COMBINED RESULTMaternity providers must advise women that they shouldexpecttoreceiveasingle(combined)resultfromthebloodtestandtheNT.

The results of the two screening tests are combined to provide a single assessment of the likelihoodthatthebabyhasDownsyndromeoranothercondition.

The laboratory will advise the result to the maternity provider who referred the woman for screening, and the maternity provider must communicatetheresulttothewoman.

Maternity providers should ensure that the woman knowsthatshecanexpectthecombinedresultswithinaweekto10daysofherlasttest.

3.8.1 First trimester combined screening

Guidelines InformationSECOND TRIMESTER MATERNAL SERUM SCREENING TIMEFRAMESMaternity providers must advise women where they can go for their blood test and when they must havethistest.

Forsecondtrimestermaternalserumscreening,maternity providers should ensure the woman knowsthatthisdoesnotincludeNT(althoughdatingscaninformationmaybeusedifavailable).

Secondtrimesterserumtimingis14–20weeksandtheoptimalsensitivityis14-18weeks.

Maternity providers should ensure that the woman knowsshecanexpecttheresultswithinaweekto10daysofthebloodtest.

3.8.2 Second trimester maternal serum screening


Guidelines InformationCOMPLETING THE LABORATORY REFERRAL FORMMaternity providers must fill in all sections of the laboratory referral form for the laboratory to be abletomakeanaccurateassessment.

Contactdetailsofthematernityproviderreferringthe woman for screening must be legible and correct.

Maternity providers must state on the referral form if the woman has seen genetic, specialist, or specialist obstetric services, due to a: • previouspregnancywithorchildwitha significant physical or learning disability • familyhistoryofageneticcondition.

Tomakeanaccurateassessment,thelaboratoryrequires: • LMPfromcertaindates • EDD • gestationalageaccordingtoscan,if available • maternalweightanddatethiswastaken • maternalage • maternalsmokingstatus • presenceofinsulindependentdiabetes mellitus • Whetherthisisamultiplepregnancy(ifso, how many) • whetherthisisanIVFpregnancyand,ifso, theeggdonor’sormother’sageattimeof donation or egg retrieval • historyofthreatenedmiscarriageinthis pregnancy • anyhistoryofapreviouspregnancywith Down syndrome or another condition screened for • copiesofanyscans(forbothtrimesters) anddetailsaboutthosescans.

3.8.3 Referring women for screening Referralsforbloodtestsshouldbemadeontheapprovedreferral(laboratory)form.ReferralsforNTultrasoundshouldbemadeinaccordancewiththePrimaryMaternityServicesNotice2007,sectionDC4,codeNT.


3.9 Laboratory processesThe laboratory will provide a report to the maternity provider who referred the woman for screening.

Guidelines InformationLABORATORY SERVICES: REPORTING INFORMATION TO THE MATERNITY PROVIDERThe laboratory is responsible for providing a first trimester combined screening or second trimester maternal serum screening result to the maternity provider who referred the woman for screening, by electronicmeansand/orhardcopyreporting.

The laboratory report will include: • screeningresult(‘increasedrisk’or‘lowrisk’) • multiplesofthemedian(MoMs)ofeach analyte (not raw numbers) • individualriskassessmentsfor: › Downsyndrome(Trisomy21) › Trisomy18(Edwardssyndrome) › Trisomy13(Patausyndrome) › Neural tube defects (for second trimester,butnotforfirsttrimester).

Theriskresultwillbecalculatedforthepregnancyat term, rather than for the gestation at the time of screening,andreportedasaproportion.

The laboratory report may include other information,forexamplethatspecialistobstetricreferral is recommended or that a rare genetic disorderisindicated.

Thescreeningcut-offpointis1:300.Thisisthethresholdthatdividesbetweenlowriskandincreasedriskresults.Forexample,aresultof1:896islowriskandaresultof1:234isincreasedrisk.

LABORATORY SERVICES: PROVISION OF SPECIALIST LABORATORY ADVICEThe laboratory is responsible for providing specialist laboratory advice to the maternity provider.

Ifspecialistlaboratoryadviceisindicated,thelaboratorywillcontactthematernityprovider.

LABORATORY SERVICES: REPORTING INFORMATION TO THE NATIONAL SCREENING UNITThe laboratory is responsible for providing reportinginformationtotheNSU.

ReportinginformationrequiredbytheNSUfromthe laboratory includes: • separatedataforfirstandsecondtrimester screening • numberofwomenscreened • ethnicityofwomenscreened • geographicallocationofwomenscreened • referrer • numberofbusinessdaysbetweenreceiptof sampleandprovisionofriskcalculation • numberofincreasedriskresults • numberoflowriskresults.



Responsibilities First Trimester Second TrimesterCollectionandtransportationofallbloodsamplesforthepurpose of antenatal screening for Down syndrome and other conditions

√ √

Supply and distribution of laboratory referral forms to maternity providers for the collection of blood specimens, pregnancy dating information and other required pregnancy and personal data

√ √

(Where available) the receipt of scan information from radiology providers of fetal measurements including NT, crown-rumplength(CRL)orbiparietaldiameter(BPD)(ifscanningisafter12weeks)

√ √

Analysisoftheappropriateanalytes(biochemicalmarkers)inmaternalseruminthefirsttrimester:Pregnancy-associatedplasmaprotein-A(PAPP-A)andfreebeta-humanchorionicgonadatrophin(ßhCG)

√

Analysisoftheappropriateanalytes(biochemicalmarkers)in maternal serum in the second trimester: alpha-fetoprotein(AFP),ßhCG,unconjugatedeostriol(µE3) and inhibinA

√

ApplicationofanalgorithmusingtheappropriatebiochemicalandultrasoundmarkerstocalculateanassessmentofriskthatapregnancymaybeaffectedbyDown syndrome or another condition screened for

√ √

Provisionoffirsttrimestercombinedscreeningandsecond trimester maternal serum screening results and information to maternity providers who have referred women for screening by telephone (in the case of increased riskresults)andbyelectronicmeansand/orhardcopy

√ √

Provisionofspecialistadvicetoandavailabilityforconsultation with maternity providers who have referred women for screening

√ √

ProvisionofreportinginformationtotheNSU √ √

3.9.1 Laboratory responsibilities


25Guidelines for maternity providers offering antenatal screening for Down syndrome and other conditions in New Zealand 25Guidelines for maternity providers offering antenatal screening for Down syndrome and other conditions in New Zealand

3.9.2 ExceptionsThe laboratory will contact the maternity provider who referred the woman for screening in the followingcircumstances.

LABORATORY SERVICES: EXCEPTIONS

Scenario ActionThe laboratory receives a blood sample for first trimestercombinedscreening,butnoNT.

The laboratory will advise the maternity provider to contact the woman about the need to have her NTperformedbefore13weeks6daysforafirsttrimestercombinedscreeningriskassessmenttobepossible.

IftheNTscanhasnotbeenperformedby13weeks6days,thelaboratorywill: • issueareporttothematernityproviderthat provides the values of the analytes • advisethatfirsttrimestercombined screening cannot be completed because the scan data was not available • recommendthatthewomanisoffered secondtrimestermaternalserumscreening.

The maternity provider should advise the woman that first trimester combined screening has not been completed and invite her to participate in secondtrimestermaternalserumscreening.

However,iftheNTscanhasbeendonebefore13weeks6days,itcanstillbesenttothelaboratoryfor first trimester combined screening to be completed.

The laboratory receives a scan result indicating the pregnancyismoreadvancedthan13weeks6days.

The laboratory will advise the maternity provider thatthewoman’sLMPsuggestssheiswithin13weeks6daysbutthescanmeasurementsindicate a more advanced pregnancy, and that first trimester combined screening will not be completed.

The maternity provider should advise the woman that first trimester combined screening has not been completed and invite her to participate in secondtrimestermaternalserumscreening.

The laboratory receives a blood sample for second trimester maternal serum screening for a woman who has already completed first trimester combinedscreening.

The laboratory will advise the maternity provider that first trimester combined screening has already been accessed by the woman for this pregnancy.

The maternity provider should advise the woman that second trimester maternal serum screening willnotbepubliclyfunded.

The laboratory receives a blood sample for second trimester maternal serum screening with an NT scanresult.

ThelaboratorywillprovideariskresultcalculationthatdoesnotincorporatetheNT.Thereportwill state that NT measurement has not been incorporatedintotheassessment.


3.10 ResultsThe maternity provider who referred the woman for screening is responsible for communicating thescreeningresultstothewoman.

Guidelines InformationRECEIVING SCREENING RESULTSThe maternity provider who referred the woman for screening is responsible for receiving screening results and ensuring that they are communicated tothewoman.

The laboratory must ensure that maternity providers have all the information required to informwomenoftheirscreeningresults.

Screening results will be completed by the laboratory within three business days after the receiptofthebloodsampleandscaninformation.Sample transit times to the laboratory may vary between regions, but should generally be within twotothreedays.

Ifthescreeningresultislowriskthelaboratorywill dispatch the results to the maternity provider bymailorelectronicmeanswithin24hoursoftheresultsbeingavailable.

Ifthescreeningresultisincreasedriskthelaboratory will contact the maternity provider by telephonewithin24hoursoftheresultsbeingavailable.Resultswillalsobedispatchedtothematernityproviderbymailorelectronically.

Maternityprovidersmustcheckthewoman’snotesto confirm if there are any results the woman did not want to be told, before communicating the results.

Iftheradiologistfindsasignificantanomalyduringthe NT scan, they may inform the woman directly and/or advise the maternity provider that urgent referralisrequired.


COMMUNICATING SCREENING RESULTSMaternity providers must understand what screening results mean and be able to present them in a clear and concise way to support womenintheirdecision-making.Thisincludesunderstandingstatisticalriskinformation.

Allresults,whetherlowriskorincreasedrisk,shouldbegiveninperson.

Anappropriateprivateandcomfortableenvironmentshouldbeprovidedforgivingresults.

Giving results may include: • discussingthelimitationsofscreening • discussingthatalowriskresultmeans thatthebabyisunlikelytobebornwithone of the conditions screened for, but it does not mean they will definitely not be born with one of these or another condition not indicated by screening • providinganopportunityforthewoman(and herfamily/whānau)toaskquestions • providinginformationaboutotherservices, including community support agencies the woman (and her family/whānau) can contact iftheyhavespecificconcerns.

Ifawomanwithalowriskresultwantsareferralto a specialist obstetrician, the maternity provider shouldmakeareferral.

ADDITIONAL SUPPORTMaternity providers must offer additional support to women who may have difficulty understanding information because of language difficulties (eg, Englishasasecondlanguage),hearingimpairmentorintellectualdisability.

Using family members or friends as interpreters is notrecommendedpractice.UseLanguageLine,aDHBinterpreter,oraNewZealandsignlanguage(NZSL)interpreter.

The woman may wish to have family/whānau memberspresent.

Women with diminished competence may wish to have an independent advocate present, to supporttheirdecision-making.Somewomenwith diminished competence may have a welfare guardian, who should be present to assist their decision-making.


Guidelines InformationCOMMUNICATING INCREASED RISK RESULTSMaternity providers must inform women of all screeningresultsindicatinganincreasedriskofDownsyndromeoranothercondition,exceptwherea woman has indicated that she does not want to betoldcertainresults.

Maternity providers must provide accurate and balancedinformationtoallwomen.

Maternityprovidersmustdiscussincreasedriskresultswithwomenassoonaspossible.

The Ministry of Health increased chance result consumer resource has been developed to facilitatethediscussionofresults.

Considerationshouldbegiventothetimingofgiving results, and whether access to support services or further information is available (eg, on publicholidays).

OFFER OF SPECIALIST OBSTETRIC REFERRALMaternity providers should offer all women with increasedriskresultsaspecialistobstetricreferral.

Womenwithincreasedriskresultsshouldbeoffered a referral to discuss their results and optionswithaspecialistobstetrician.

Acceptanceofreferraldoesnotmeanacceptanceofdiagnostictesting.

The maternity provider should discuss what an appointment with a specialist obstetrician might involveandwhatthewoman’soptionsmightbe.

PROVISION OF INFORMATION ABOUT OPTIONS FOR SPECIALIST REFERRALMaternity providers must provide information about the options available for specialist obstetric referralanddiagnostictesting.

The woman should be given information about diagnostic testing including: • Chorionicvillussampling(CVS)canbe performedfrom11–14weeksofpregnancy butistypicallyperformedbetween10and 13weeks.CVSispresentlyrestrictedto afewsites.CVSresultsmaytakeoneto threeweeks. • Amniocentesiscanbeperformedfrom14 weeksofpregnancyandistypically performedbetween15and20weeks. Amniocentesisresultsmaytakeoneto threeweeks. • Therearerisksassociatedwithboth CVSandamniocentesis.Bothprocedures carryamiscarriageriskofapproximately1 percent above the spontaneous miscarriage rate.Becauseofthisrisk,somewomen may decide not to have these tests (or choosenottoparticipateinscreening).

Adecisionaboutdiagnostictestinginvolvesaseparate informed consent process after specialist obstetricconsultation.

Informedconsentfordiagnostictestingistheresponsibility of the specialist who performs the procedure.

3.10.1 Increased risk results


3.11 Genetic counselling and other referralsMaternity providers should be able to provide women with information about other relevant supportservicesintheirareaandhowtoaccessthem,ifrequested.

Guidelines InformationGENETIC COUNSELLING SERVICESMaternity providers should advise women with increasedriskresultsabouttheavailabilityofgeneticcounsellingservices.

Womenwithincreasedriskresultswillusuallyhave an appointment with a specialist obstetrician asthefirststepaboutmakinganinformeddecisionaboutwhattodonext.However,somewomenmayalsochoosetotalktoGeneticServices.

Genetic Services are physically located in Auckland,Wellington,andChristchurch.Telephone counselling is available to women who cannotaccessthesecentres.

OTHER REFERRALSMaternity providers must provide information about medical and non-medical services the woman mayaccesstohelphermakedecisionsaboutthemanagementofherpregnancy.

Maternity providers should find out about services intheirareaandhowtoaccessthem.Servicesinclude: • obstetricians • paediatricians • GeneticServices • counsellors • interpreters • disabilitysupportservices • culturallyappropriatevoluntaryagencies • consumersupportproviders/associations • ultrasoundproviders.

Maternity providers should advise what options are available and the timeframes of these, and find waystoprovidepracticalsupportandassistance.


3.12 Funding of diagnostic testingDiagnostic testing is publicly funded for women who have: • anincreasedriskresult • anabnormalultrasoundscan(structuralabnormalities) • previouslyhadababywithacongenitalanomaly • afamilyhistoryofDownsyndromeand/orotherconditions,ifrecommendedbyGenetic Services • aknowncarrierstatus,orapartnerwithaknowncarrierstatus,ifrecommendedby GeneticServices.

Insomeareas,diagnostictestingisalsofundedforwomenwhoareagedover35years.However, international best practice does not support direct referral to diagnostic testing based onage.

3.13 Data collection, monitoring and reportingThe data reported by the laboratory to the NSU includes the: • numberofwomenscreened • ethnicityofwomenscreened • geographicallocationofwomenscreened • referrer • numberofbusinessdaysbetweenreceiptofsampleandprovisionofriskcalculation • numberofincreasedriskresults • numberoflowriskresults • numberofrepeatsamplerequests.

Dataisprovidedseparatelyforfirstandsecondtrimesterscreening.

While complete data on maternity services and pregnancy outcomes are not readily collated in NewZealand,thiswillimproveovertime.Monitoringandevaluationwillfollowthescreeningpathway and assess process and outcomes, with the aim of assisting the ongoing development of the quality improvements for antenatal screening for Down syndrome and other conditions andimprovingequityofaccesstoscreening.

Where feasible and appropriate, indicators will be calculated and reported by: • DHB • ethnicity • deprivationstatus • firstandsecondtrimesterscreening.


APPENDIX ONE: GLOSSARY OF TERMSAmniocentesis is a procedure involving the withdrawal of a small amount of amnioticfluidwhichcontainsfetalcells.Thesampleisusedtoobtainfetalchromosomesforkaryotypeanalysis.

Alpha-fetoprotein(AFP)isabiochemicalmarkerusedinsecondtrimestermaternalserumscreeningforneuraltubedefectsandDownsyndromeandotherconditions.

Beta-humanchorionicgonadotropin(ßhCG)isabiochemicalmarkerusedinfirsttrimestercombined and second trimester maternal serum screening for Down syndrome and other conditions.

BiparietalDiameter(BPD) is the distance between the parietal bones at their widest point as measuredduringafetalultrasound.

Chorionicvillussampling(CVS) is a procedure involving the withdrawal of a smallamountofchorionicvilli.Thesampleisusedtoobtainchromosomesforkaryotypeanalysistoidentifysomegeneticdisorders.

Crown-rumplength(CRL)meansthedistancefromthetopofthefetalskulltothebottomofthespine,measuredduringfetalultrasound.

Cut-offpointisthevalueofascreeningvariableatwhichanindividualismorelikelytobehelpedthanharmedbytheofferofadiagnostictest.Thispointformsthedivisionbetweenlowriskandincreasedrisk.InbothscreeningoptionsforDownsyndromeandotherconditionsthecut-offpointis1:300.

Afalse positive result is a positive screening result for a condition in a person who doesnothavethecondition.

Afalse negative result is a negative screening result for a condition in a person who hasthecondition.

InhibinAisabiochemicalmarkerusedinsecondtrimestermaternalserumscreeningforDownsyndromeandotherconditions.

Karyotypeisadepictionofallthechromosomesinanindividualcell.Anychromosomalabnormalitythatcanbeviewedviaamicroscopewillbevisibleinthekaryotype.Themostcommon of these include: • Trisomies,triploidyandsexchromosomeabnormalities • Structuralgeneticabnormalities,suchasinversionsandtranslocations,deletionsand duplicationsofchromosomes.

Lastmenstrualperiod(LMP) is the estimated or actual date of the first day of awoman’slastmenstrualperiod.

Multiple of the Median (MoM) isameasurewhichcomparesthevaluesofabiochemicalmarkerinanindividualsamplewiththemedianvalueofthatbiochemicalmarkerinotherwomenatthesamegestation.

Nuchal translucency (NT)isanultrasoundmarkerwhichmeasuresthefluid-filledspaceinthetissueatthebackofafetus'neckandisamarkerforchromosomalandotheranomalies.


Pregnancy-associatedplasmaproteinA(PAPP-A)isabiochemicalmarkerusedinfirsttrimestercombinedscreeningforDownsyndromeandotherconditions.

Radiologist is a health practitioner who is, or is deemed to be, registered by the MedicalCouncilofNewZealand(establishedbytheHealthPractitionersCompetenceAssuranceAct2003)inthevocationalscopeofdiagnosticandinterventionalradiologyandholdsanannualpracticingcertificate.

Screeningisawayofidentifyingagroupofpeoplewhoaremorelikelythanotherstohaveacondition.Thescreeningprocessinvolvestestingpeople(whomaynothavesymptoms)forthepresenceofthecondition,andpredictingthelikelihoodthattheyhavethecondition.AntenatalscreeningforDownsyndromeandotherconditionspredictsthelikelihoodoftheconditionsbeingpresentinthefetus.

Sensitivityistheabilityofscreeningtoidentifypersonswiththeconditionscreenedfor.Atestwithhighsensitivitywillhavefewfalsenegativeresults.

Specificity is the ability of screening to identify persons who do not have the conditionscreenedfor.Atestwithhighspecificitywillhavefewfalsepositiveresults.

Spina bifida isaneuraltubedefectmarkedbycongenitalcleftofthespinalcolumnusuallywithhernialprotrusionofthemeningesandsometimesthespinalcord.

Trisomy18(Edwardssyndrome) is a chromosomal condition associated with severeintellectualdisabilityandabnormalitiesinmanypartsofthebody.Trisomy18ischaracterised by a low birth weight, a small, abnormally shaped head, a small jaw andmouth, clenched fists with overlapping fingers, heart defects, and abnormalities of otherorgans.Duetothepresenceofseverallife-threateningmedicalproblems,babieswithTrisomy18maybestillborn,andalmostallwilldiewithintheirfirstmonth.

Trisomy13(Patausyndrome) is a chromosomal condition associated with severeintellectualdisabilityandphysicalabnormalitiesinmanypartsofthebody.Trisomy13ischaracterised by heart defects, brain or spinal cord abnormalities, very small or poorlydevelopedeyes(microphthalmia),extrafingersand/ortoes,anopeninginthelip(acleftlip)withorwithoutanopeningintheroofofthemouth(acleftpalate),andweakmuscletone(hypotonia).Duetothepresenceofseverallife-threateningmedicalproblems,themajorityofbabieswithTrisomy13arestillborn,ordiewithintheirfirstdaysorweeksoflife.

Unconjugatedoestriol(μE3) isabiochemicalmarkerusedinsecondtrimestermaternalserumscreeningforDownsyndromeandotherconditions.

ForfurtherinformationrefertotheNHSglossaryofscreeningterminologyathttp://www.screening.nhs.uk/screening


APPENDIX TWO: RESOURCES AND CONTACTS Contactdetailsforsupportservicesandsourcesoffurtherinformationarelistedhere. Thislistshouldbesupplementedbythelocalorregionalserviceswithinyourownnetworks.

Auckland District Health BoardManagementofBabieswithDownSyndrome http://www.adhb.govt.nz/newborn/Guidelines/Anomalies/DownSyndrome.htm

Australian Centre for Genetics EducationDownSyndromeFactSheethttp://www.genetics.com.au/pdf/factsheets/fs28.pdfChangestoChromosomes–Number,SizeandStructureFactsheet http://www.genetics.com.au/pdf/factsheets/fs06.pdf

Antenatal Results and Choices (UK)http://www.arc-uk.org/

CCS Disability Actionhttp://www.ccs.org.nzTel.0800227200

Disability Services http://www.moh.govt.nz/disability

Down’s Syndrome Association (UK)ANewParent’sGuidehttp://www.downs-syndrome.org.uk

Down syndrome onlinehttp://www.down-syndrome.org

Fetal Medicine Foundation, Londonhttp://www.fetalmedicine.com/FMF/The11–13+6WeeksScanhttp://www.studiolift.com/fetal/site/FMF-English.pdf

Genetic Services, New Zealand NorthernandMidlandRegionTel:0800476123

CentralRegionTel:0508364436

SouthernRegionTel:0508364436

Health and Disability Commissionerhttp://www.hdc.org.nz/

Human Genetic Society of Australasia (HGSA)http://www.hgsa.com.au

IHChttp://www.ihc.org.nz Tel.(04)4722247

International Mosaic Down Syndrome AssociationBookletforprofessionalshttp://www.imdsa.org/Information/professional.htm


Kiwi FamiliesLinkstodisabilitysupportarticleshttp://www.kiwifamilies.co.nz/

LabPLUShttp://www.labplus.co.nzTel.08005227587

Ministry of HealthPrimaryMaternityServicesNotice2007http://www.moh.govt.nz/moh.nsf/indexmh/maternity-section88noticeGuidelinesforConsultationwithObstetric&RelatedSpecialistServices(ReferralGuidelines).Wellington: Ministry of Health http://www.moh.govt.nz/moh.nsf/pagesmh/6257/$File/maternity-referral-guidelines-may07.pdf

National Health Service (UK)AntenatalScreening:Introductionhttp://www.nhs.uk/conditions/Antenatal-screening/Pages/Introduction.aspxBriefdescriptionsofothertrisomies(13Patau;18Edwards),monosomy(Turner)andalsoKlinefelters,XXX,YYandfeatureswhichmightidentifythemantenatallyhttp://www.perinatal.nhs.uk/car/anomaly/chromosome/chromosome.htm

National Screening Committee (UK)FetalAnomalyScreeningProgramme-ScreeningforDown’sSyndrome:UKNSCPolicyrecommendations2007-2010:ModelofBestPracticehttp://www.dh.gov.uk/en/Publicationsandstatistics/Publications/PublicationsPolicyAndGuidance/DH_084732

National Screening Unit http://www.nsu.govt.nz

New Zealand Down Syndrome Associationhttp://www.nzdsa.org.nzTel.0800NZDSAI(0800693724)Email:[email protected]

New Zealand Federation of Disability Information Centreshttp://www.nzfdic.org.nz

New Zealand Organisation for Rare Disordershttp://www.nzord.org.nz

Pacific Information Advocacy Support Serviceshttp://www.piass.org.nz

Parent and Family Resource Centrehttp://www.parentandfamily.org.nz

Parent to Parent http://www.parent2parent.org.nz

Royal Australian and New Zealand College of Obstetricians and Gynaecologistshttp://www.ranzcog.edu.au/Prenatalscreeningtestsfortrisomy21(Downsyndrome),trisomy18(Edwardssyndrome)andneuraltubedefectsJuly2007http://www.ranzcog.edu.au/publications/statements/C-obs4.pdf

Society of Obstetricians and Gynaecologists of Canadahttp://www.sogc.org/guidelines/documents/gui217CPG0810.pdf

What Everyone Keeps Askinghttp://www.weka.net.nz


APPENDIX THREE: BIBLIOGRAPHY

ChangChoongT.2005.Antenatal Screening for Down Syndrome in New Zealand: Time for a national screening policy? DepartmentofObstetricsandGynaecology,FacultyofMedicalandHealthSciences,UniversityofAuckland.

GillamL.1999.Prenataldiagnosisanddiscriminationagainstthedisabled.Journal of Medical Ethics25(2):163(HealthModule).

IrvingL.2004. Nuchal translucency screening for Down’s syndrome: the midwife’s role. New Zealand College of Midwives Journal31:18–21.

MinisterforDisabilityIssues.2001.New Zealand Disability Strategy. Wellington: Ministry of Health.

MinistryofHealth.2007.Report on Maternity: Maternal and Newborn Information 2004. Wellington:MinistryofHealth.

NationalScreeningCommittee(UK).2007.Prenatal Screening – Working Standards for Down’s Syndrome Screening 2007.NHSNationalDown’sSyndromeScreeningpathwayforEngland.

NSU.2005.Improving Quality: A framework for screening programmes in New Zealand. Wellington.MinistryofHealth.

NSU.2007.Antenatal Down syndrome Screening Advisory Group Report, January 2007. Wellington:MinistryofHealth.

RosenT,D’AltonME.2005.Down Syndrome screening in the first and second trimesters: what do the data show?SeminarsinPerinatology29:367–75.

StoneP.2005.Prenatal testing for aneuploidy in New Zealand: time for action. New Zealand Medical Journal 118(1217).

StoneP,AustinD.2006.Report to the National Screening Unit: Assessment of prenatal screening for Down syndrome in New Zealand.Auckland:UniServicesLimited.

ToiteTaiao:theBioethicsCouncil.2008.Who Gets Born? A report on the cultural, ethical and spiritual aspects of pre-birth testing by Toi te Taiao: the Bioethics Council.URL:http://www.bioethics.org.nzPublicationNumber:BC19.

YangQ,RasmussenSA,FriedmanJM.2002.Mortality associated with Down's syndrome in the USA from 1983 to 1997: a population-based study.Lancet359:1019–25.

guidelines for maternity providers offering … guidelines for maternity providers offering...

Documents