Multifetal GestationMultifetal Gestation

twin

singleton

triplets

……

septuplets

Factors that Influence TwinningFactors that Influence Twinning

RaceRaceHeredityHeredityMaternal Age and ParityMaternal Age and ParityNutritional FactorsNutritional FactorsPituitary GonadotropinPituitary Gonadotropin Infertility TherapyInfertility TherapyAssisted Reproductive Technology (ART)Assisted Reproductive Technology (ART)

ComplicationsComplications

FetalFetal malformationsmalformations placental vascular anastomosiplacental vascular anastomosi

s (twin-twin transfusion syndrs (twin-twin transfusion syndrome, TTTS)ome, TTTS)

fetal-growth restrictionfetal-growth restriction preterm delivery preterm delivery perinatal mortalityperinatal mortality …………

MaternalMaternal preeclampsiapreeclampsia postpartum postpartum

hemorrhagehemorrhage maternal deathmaternal death …………

Labor and delivery complicationsLabor and delivery complications

preterm laborpreterm laboruterine contractile dysfunctionuterine contractile dysfunctionabnormal presentationabnormal presentationumbilical cord prolapseumbilical cord prolapsepremature separation of the placentapremature separation of the placenta immediate postpartum hemorrhage immediate postpartum hemorrhage

Etiology Etiology

ova–ova–dizygoticdizygotic or or fraterfraternal twinsnal twins

maturation and fertilizmaturation and fertilization of two ovaation of two ova

monozygoticmonozygotic or or identical twinsidentical twins

Genesis of Monozygotic TwinsGenesis of Monozygotic Twins

"Vanishing Twin" "Vanishing Twin"

one twin is lost or "vanishes" one twin is lost or "vanishes" maternal serum alpha-fetoprotein level ↑maternal serum alpha-fetoprotein level ↑ amnionic fluid alpha-fetoprotein level ↑amnionic fluid alpha-fetoprotein level ↑ amnionic fluid acetylcholinesterase assayamnionic fluid acetylcholinesterase assay ++

Determination of ChorionicityDetermination of Chorionicity

Sonographic EvaluationSonographic EvaluationPlacental ExaminationPlacental Examination Infant Sex and ZygosityInfant Sex and Zygosity

DiagnosisDiagnosis

History and Clinical ExaminationHistory and Clinical ExaminationSonographySonography Radiological ExaminationRadiological ExaminationBiochemical TestsBiochemical Tests

large uterus for gestational agelarge uterus for gestational age

Multiple fetusesMultiple fetuses Elevation of the uterus by a distended bladderElevation of the uterus by a distended bladder Inaccurate menstrual historyInaccurate menstrual history HydramniosHydramnios Hydatidiform moleHydatidiform mole Uterine leiomyomasUterine leiomyomas A closely attached adnexal massA closely attached adnexal mass Fetal macrosomia (late in pregnancy)Fetal macrosomia (late in pregnancy)

Duration of GestationDuration of Gestation

Unique ComplicationsUnique Complications

Vascular Anastomoses between FeVascular Anastomoses between Fetusestuses

Antepartum Management of Twin PregnancyAntepartum Management of Twin Pregnancy

Delivery of markedly preterm neonates be Delivery of markedly preterm neonates be preventedprevented

Fetal-growth restriction be identified and Fetal-growth restriction be identified and afflicted fetuses be delivered before they afflicted fetuses be delivered before they become moribundbecome moribund

Fetal trauma during labor and delivery be Fetal trauma during labor and delivery be avoidedavoided

Expert neonatal care be availableExpert neonatal care be available

Recommendations for intrapartum managementRecommendations for intrapartum management

An appropriately trained obstetrical attendant should An appropriately trained obstetrical attendant should remain with the mother throughout labor. Continuouremain with the mother throughout labor. Continuous external electronic monitoring is employed. If mems external electronic monitoring is employed. If membranes are ruptured and the cervix dilated, then simbranes are ruptured and the cervix dilated, then simultaneous evaluation of both the presenting fetus by ultaneous evaluation of both the presenting fetus by internal electronic monitoring and the remaining sibliinternal electronic monitoring and the remaining sibling(s) by external monitors is typically usedng(s) by external monitors is typically used

Blood transfusion products are readily availableBlood transfusion products are readily available An intravenous infusion system capable of deliverinAn intravenous infusion system capable of deliverin

g fluid rapidly is established. In the absence of hemog fluid rapidly is established. In the absence of hemorrhage, lactated Ringer or an aqueous dextrose solurrhage, lactated Ringer or an aqueous dextrose solution is infused at a rate of 60 to 125 mL/hrtion is infused at a rate of 60 to 125 mL/hr

Recommendations for intrapartum managementRecommendations for intrapartum management

An obstetrician skilled in intrauterine identification of fetal An obstetrician skilled in intrauterine identification of fetal parts and in intrauterine manipulation of a fetus should be parts and in intrauterine manipulation of a fetus should be presentpresent

A sonography machine is made readily available to help A sonography machine is made readily available to help evaluate position and status of the remaining fetus(es) aftevaluate position and status of the remaining fetus(es) after delivery of the firster delivery of the first

Experienced anesthesia personnel are immediately availExperienced anesthesia personnel are immediately available in the event that intrauterine manipulation or cesareable in the event that intrauterine manipulation or cesarean delivery is necessaryan delivery is necessary

For each fetus, two attendants, one of whom is skilled in rFor each fetus, two attendants, one of whom is skilled in resuscitation and care of newborns, are appropriately inforesuscitation and care of newborns, are appropriately informed of the case and remain immediately availablemed of the case and remain immediately available

The delivery area should provide adequate space for all tThe delivery area should provide adequate space for all team members to work effectively. Moreover, the site museam members to work effectively. Moreover, the site must be appropriately equipped to provide maternal and neont be appropriately equipped to provide maternal and neonatal resuscitationatal resuscitation

Presentation and PositionPresentation and Position

admission for delivery: cephalic-cephalic, admission for delivery: cephalic-cephalic, cephalic-breech, and cephalic- transversecephalic-breech, and cephalic- transverse

Vaginal deliveryVaginal delivery

WhenWhenHowHowEvaluationEvaluation

Internal podalic versionInternal podalic version

Cesarean DeliveryCesarean Delivery

ComplicationsComplicationsSecondarySecondaryRare situationRare situation

Twin-Twin Transfusion Syndrome Twin-Twin Transfusion Syndrome (TTTS)(TTTS)

blood is transfused from a donor blood is transfused from a donor twin to its recipient siblingtwin to its recipient sibling

the donor becomes anemic and itthe donor becomes anemic and its growth may be restricted s growth may be restricted

the recipient becomes polycythethe recipient becomes polycythemic and may develop circulatory mic and may develop circulatory overload manifest as hydropsoverload manifest as hydrops

donor twin is pale, and its recipiedonor twin is pale, and its recipient sibling is plethoricnt sibling is plethoric

Diagnosis--sonographic suspedtedDiagnosis--sonographic suspedted

MonochorionicityMonochorionicity same-sex gendersame-sex gender hydramnios defined if the largest vertical pocket ihydramnios defined if the largest vertical pocket i

s > 8 cm in one twin and oligohydramnios defines > 8 cm in one twin and oligohydramnios defined if the largest vertical pocket is < 2 cm in the otd if the largest vertical pocket is < 2 cm in the other twinher twin

umbilical cord size discrepancyumbilical cord size discrepancy cardiac dysfunction in the recipient twin with hydcardiac dysfunction in the recipient twin with hyd

ramniosramnios abnormal umbilical vessel or ductus venosus Doabnormal umbilical vessel or ductus venosus Do

ppler velocimetryppler velocimetry significant growth discordance. significant growth discordance.

Quintero staging systemQuintero staging system

Stage I–discordant amnionic fluid volumes as deStage I–discordant amnionic fluid volumes as described above, but urine still visible sonographicscribed above, but urine still visible sonographically within the donor twin's bladder ally within the donor twin's bladder

Stage II–criteria of stage I, but urine is not visible Stage II–criteria of stage I, but urine is not visible within the donor's bladder within the donor's bladder

Stage III–criteria of stage II and abnormal DopplStage III–criteria of stage II and abnormal Doppler studies of the umbilical artery, ductus venosus,er studies of the umbilical artery, ductus venosus, or umbilical vein or umbilical vein

Stage IV–ascites or frank hydrops in either twinStage IV–ascites or frank hydrops in either twin Stage V–demise of either fetus Stage V–demise of either fetus

Disorders of Amnionic Fluid Disorders of Amnionic Fluid Volume Volume

The role of amnionic fluidThe role of amnionic fluid

a physical spacea physical spacepromotes normal fetal lung development promotes normal fetal lung development avert compression of the umbilical cordavert compression of the umbilical cord

Permitting fetal movement and the development of the Permitting fetal movement and the development of the musculoskeletal system. musculoskeletal system.

Swallowing of amniotic fluid enhances the growth and Swallowing of amniotic fluid enhances the growth and development of the gastrointestinal tract. development of the gastrointestinal tract.

The ingestion of amniotic fluid provides some fetal nutriThe ingestion of amniotic fluid provides some fetal nutrition and essential nutrients. tion and essential nutrients.

Amniotic fluid volume maintains amniotic fluid pressure Amniotic fluid volume maintains amniotic fluid pressure thereby reducing the loss of lung liquid - an essential cthereby reducing the loss of lung liquid - an essential component to pulmonary development. (Nicolini, 1989). omponent to pulmonary development. (Nicolini, 1989).

Protects the fetus from external trauma. Protects the fetus from external trauma. Protects the umbilical cord from compression. Protects the umbilical cord from compression. It's constant temperature helps to maintain the embryIt's constant temperature helps to maintain the embry

o's body temperature. o's body temperature. It's bacteristatic properties reduces the potential for infIt's bacteristatic properties reduces the potential for inf

ection.ection.

Pathway

Pathwayml/day to the fetus

ml/day to amnioticfluid

Fetal swallowing 500-1000 -

Oral secretions - 25

Secretions from the respiratory tract 170 170

Fetal urination - 800-1200

Intramembranous flow across the placenta, umbilical cord and fetal

200-500 -

Transmembraneous flow from the amniotic cavity into the uterine circulation

- 10

Normal Amnionic Fluid VolumeNormal Amnionic Fluid Volume

1 L by 36 weeks, decreases thereafter to les1 L by 36 weeks, decreases thereafter to less than 200 mL at 42 weekss than 200 mL at 42 weeks

Diminished fluid is termed Diminished fluid is termed oligohydramniosoligohydramniosmore than 2 L of amnionic fluid is termed more than 2 L of amnionic fluid is termed hydhyd

ramniosramnios or or polyhydramniospolyhydramnios

Measurement of Amnionic FluidMeasurement of Amnionic Fluid

amnionic fluid indexamnionic fluid index, , AFIAFI adding the vertical depths of the largest poadding the vertical depths of the largest po

cket in each of four equal uterine quadrantcket in each of four equal uterine quadrantss

hydramnios : hydramnios : ＞＞ 24 cm 24 cm

Sonogram of a pocket of amniotic fluid in a patient with hydrops fetalis and polyhydramnios. Two small segments of umbilical cord (arrows) are seen traversing the measured pocket of amniotic fluid. The placenta (P), which appears normal to prominent in this case, is, in fact, abnormally thickened.

HydramniosHydramnios

CausesCauses fetal malformationsfetal malformations gastrointestinal anomalies nonimmune hydrops chromosomal abnormalities central nervous system

TTTSTTTS fetal pseudohypoaldosteronismfetal pseudohypoaldosteronism fetal Bartter or hyperprostaglandin E syndromefetal Bartter or hyperprostaglandin E syndrome fetal nephrogenic diabetes insipidusfetal nephrogenic diabetes insipidus placental chorioangiomaplacental chorioangioma fetal sacrococcygeal teratomafetal sacrococcygeal teratoma maternal substance abusematernal substance abuse

OligohydramniosOligohydramnios

Associated ConditionsAssociated Conditions

FetalFetal Chromosomal abnormalities Congenital anomalies Growth restriction Demise Postterm pregnancy Ruptured membranes

Associated ConditionsAssociated Conditions

PlacentaPlacenta Abruption Twin-twin transfusionMaternalMaternal Uteroplacental insufficiency Hypertension Preeclampsia Diabetes

Associated ConditionsAssociated Conditions

DrugsDrugs Prostaglandin synthase inhibitors Angiotensin-converting enzymeinhibitors IdiopathicIdiopathic

The EndThe End