Sarcina multipla

Marius Bogdan Muresan Centrul de Medicina Fetala - Spital PREMIERE

Timisoara

MULTIPLEPREGNANCY

• Presenceofmorethanonefetusinthegraviduterus

• 1%ofallpregnancies• Hellin’sRule

– Twins:1in80– Triplets:1in80×80–Quadruplets:1in80×80×80….

• Gemellology:Studyoftwins

• ZYGOSITY-ReferstotheTypeofConception.-onlydeterminedbyDNAtesting

• CHORIONICITY-TypeofPlacentation-prenatallybyultrasound-postnatallybyexamining membranes.

1.ZYGOSITY

DizygoticTwins

MonozygoticTwins

1.DIZYGOTICTWINS/BINOVULAR75%

Fertilisationof2ovabydifferentspermatozoa.

Eachtwinhasitsownplacenta,chorion,amnion.

Hencealwaysdichorionic,diamniotic.

Factorsaffecting-ethnicgroup-increasingmaternalage-increasingparity-Familyhistoryoftwinning-ovulationinductionwithclomiphenecitrate/gonadotrophinsresultinginmultipleovulation.

DIZYGOTICTWINS/BINOVULAR

2.MONOZYGOTIC/IDENTICAL

25%Resultfromsplittingofasinglefertilizedovum

Alwayssamesexandlookalike.[IDENTICAL]

Rateofmonozygotictwinningisrelativelyconstant,notaffectedbyanyfactors.

Trueetiologyunknown.

Typeofplacentationisdeterminedbythetimeofsplitting

MONOZYGOTICTWINS

MONOZYGOTIC/IDENTICAL

ziua 1-3

ziua 4-8 ziua 8-13

= 1/3 din MZ

= 2/3 din MZ

2.CHORIONICITY

• TypeofPlacentation

• Postnatally-ExaminationofMembranes

• Prenatally-ByUltrasound

• Idealtimeforassesmentisbefore14weeks

Whichismoreimportant–zygosityorchorionicity??

CHORIONICITY………Why????

• Dichorionictwinscanbeeithermono/dizygotic.• Dichorionictwinsdevelopastwodistinctorgans.–sonorisk.

DiZigotic MonoZigotic DiCorionicDiCorionic

CHORIONICITY………Why????• Monochorionictwinshaveincreasedvascularanastomosesbetweenthetwocirculation

–sohighrisk!!

UltrasoundDeterminationofChorionicity

• Numberofsacs.[before10weeks]✓ 2sacs–dichorionic✓ Singlesac-monochorionic

• Placenta

• Sex

• Intertwinmembrane✓ thickerandmoreechogenicindichorionic.

Ultrasounddifferentiationofchorionicity

Criterion Monochorionic Dichorionic

Placenta Single DoubleFetalSex -------- DiscordanceMembrane <2mm >2mmNo:oflayersinmembrane

2layers 4layers

Twinpeaksign Absent Present

• Twinpeak/Lambdasign-characteristicofdichorionicpregnancies-chorionictissuebetween2layersofintertwinmembraneattheplacentalorigin

• TSign–inmonochorionic,nochorionictissue

• Ifnomembraneisseeninbetween–monochorionicmonoaniotic

FETALCOMPLICATIONS✓ Perinatalmortality:6times

✓ Morbidity:2-3times

✓ Monochorionic-morbidity/mortalitytwiceasthatofdichorionic.-additionalriskfromTTS

✓ Monoamniotictwins-50%mortality.

✓ Maincauseofadverseoutcomeis1.Prematurity

2.IUGR✓ Cerebralpalsy,neurodevelopmentalimpairment,lowerIQscores.

✓ Monochorionictwins:1.TTTS2.TAPS5.Monoamniotictwinning

3.SelectiveFGR6.Conjoinedtwinning

4.TRAP-Acardiacfetus

Prematurity

• Singlemostimportantcauseofperinatalmortalityandmorbidity.

• Ensuredeliveryinatertiarycarecentre.!!

Monochorionictwinscomplications

1.TTTS

2.TAPS

3.SelectiveFGR

4.TRAP-Acardiacfetus

5.Monoamniotictwinning

6.Conjoinedtwinning

placentalvascular

anastomoses

MCTwinscomplications-placentalvascularanastomoses

1.TTTS

2.TAPS

3.SelectiveFGR

4.TRAP-Acardiacfetus

Twin–twinTransfusionSyndrome[TTTS]

OccursinmonochorionicplacentationduetoAVanastomoseswithresultantflowinonedirection.

IUGR

Canaffectoneorbothfetuses.

Monochorionic>Dichorionic.

FETALDEMISE

SINGLEFETALDEMISE

Monochorionic-25%riskoftwindeath,25%riskofneurologicaldamageinsurvivingtwin.• Dilemmaexistswhethertodeliverearlyornot• Terminatedassoonasothertwiniscapableofextrauterinesurvival

Dichorionic–nosuchrisk

• Conservativemanagement

SINGLEFETALDEMISEinMCTwins

Deathofonetwin

Suddenacuteshiftofbloodfrom

survivingtwinto

deadfetus

NEUROLOGICALDAMAGE

insurvivingTWIN

MECHANISMPUMPTWIN ACARDIACTWIN

PUMPTWINACARDIACTWIN

Monochorionictwinscomplications

1.TTTS

2.TAPS

3.SelectiveFGR

4.TRAP-Acardiacfetus

5.Monoamniotictwinning

6.Conjoinedtwinning

MonochorionicMonoamniotictwinning

Seeninlessthan1%ofalltwinpregnancies

Lateintrauterinedeathduetocordentanglement.

Bestdiagnosedin1sttrimester–absenceofinterveningmembrane.

Colourdoppler–cordentaglement

Fetalloss–50-70%

HenceelectiveCSat32-34weeks.

CongenitalAnomalies

STRUCTURALMALFORMATIONS• Uniquetotwins–conjoinedtwins,Acardiacfetus

• Nonspecificbutcommonintwins–CHD,Anencephaly

• Posturaldeformities–Talipes&CongenitaldislocationofHipCHROMOSOMALANOMALIES

• Dizygotic–independentrisk,butbothwillnotbeinvolved

• Monozygotic–sameriskasthatofsingleton,bothaffected

• Down’ssyndrome

ManagementofAnomaliesinDC

DICHORIONICPREGNANCY

(DC)

Ifonefetusisabnormal

Selectivefeticideusing

KCl

ManagementofAnomaliesinMC

MonochorionicPREGNANCY

(MC)

Ifonefetusisabnormal

SelectivefeticideintrafetalLASER

THM

Discordanta DC MC Specific MC

Structurala 1 sau 2 1 sau 2TRAP -

Ambii feti afectati

Cromozomiala ! Nu Exista Ambii feti afectati

LA ? TTTS Ambii feti afectati

Crestere ? sIUGR Ambii feti afectati

PSV-MCA ? TAPS Ambii feti afectati

1 fat - IUFD ? fat 2 ! Ambii feti afectati

Multumesc

a 3-a editie-Timisoara-

26-28 mai 2017