Multiple Pregnancy

Muhammad Taimur AfridiRoll No : 08-127

•Incidence :•Monozygotic twins - 4/1000 births•Dizygotic twins – 2/3rds, race, age, assisted conception•Triplets – 1 in 7000 to 10,000 births•Quadruplets – 1 in 600,000 births

• Almost every maternal and obstetric problem occursmore frequently in multiple Pregnancy

• Perinatal mortality rate in twins is 5 times higher andin triplets 10 times higher than in singletons

•Zygosity refers to the type of conception

•Chorionicity denotes the type of placentation

•Chorionicity rather than zygosity determines outoutcome

Zygosity and Chorionicity

Mechanism of dizygotic twinning

Fertilization of a single ovum

Similar sex

Genetically identical

Fertilization of 2 separate

ova

MONOCHORIONIC TWINS

•3-8 DAYS LATER (60-70%) Within 72 hours (18-32%)

MONOCHORIONIC TWINS

•8-12 DAYS LATER (1-2%)

•12-13 DAYS LATER

(0.5%)

Maternal responses

Cardiac output, GFR and renal blood flowPlasma volume by 1/3 > singletonsRed cell mass 300 ml > singletons

Hematocrit and hemoglobinIron stores in 40% of women with twins

Multiple pregnancy

DIAGNOSIS

Patient profile:

Etiological factors:

positive past history and family history specially maternal, race, age

Assisted reproductive technology

Early pregnancy:

Hyperemesis, excessive weight gain

minor complications of pregnancy such as backache, edema, varicose veins, hemorrhoids, striae, etc

PHYSICAL SIGNS

General:

Pallor, weight gain, excessive pedal edema/ varicose veins

Pregnancy Induced Hypertension(PIH) and Pre-eclampsia (5-10times more)

Abdominal:

Size > Date especially in midpregnancy

Multiple fetal parts

Auscultation of FHS:

2 different recordings by 2 observers and a difference > 10 bpm

Differential diagnosis

• Elevation of the uterus by a distended

bladder

• Inaccurate menstrual history

• Hydramnios

• Hydatidiform mole

• Uterine fibroids

• A closely attached adnexal mass

• Fetal macrosomia (late in pregnancy)

Ultrasonography

• Detect multifetal gestation 99% before

26 weeks

• Confirm fetal number [ 2 sacs or 2fetal

heads in 2 perpendicular planes]

• Diagnose type and presentation and

position and relation to each other

• Exclude congenital abnormalities/

conjoint twin

MATERNAL

COMPLICATIONSSymptoms – hyperemesis, aches and pains

of pregnancy worsen

Hypertensive disease of pregnancy

Preterm delivery

Premature rupture of membranes

Polyhydramnios

Placenta praevia

Malpresentation

Delivery complications (operative delivery, placental abruption, cord accidents)

Postpartum hemorrhage, depression

FETAL COMPLICATIONS

Spontaneous early pregnancy loss

Prematurity

Intra-uterine growth restriction

Cerebral palsy - related to gestational age, 3 times in twins, > 10 times in triplets

Intrapartum trauma

Monochorionic twins – specific complications

Antenatal care

• Routine booking investigationsFolic acid supplementationanemia – treat immediatelySupport symptomatically

• Serial growth scans :

Dichorionic :4 weekly from 24 weeks

Monochorionic : 2 weekly from 18 weeks- Liquor volume- Doppler study of umbilical artery

Intrapartum management

•Presence of skilled obstetrician, anesthetist and neonatologist available at delivery•Reliable intravenous access•Cardiotocograph with dual monitoring capability•Portable ultrasound scanner•Delivery bed with lithotomy stirrups•Obstetric forceps or vacuum apparatus• active management of third stage: Uterotonics•Immediate availability of blood•Facilities and staff for emergency cesarean section

Monochorionic Monoamniotic twins

•3 - 12 x perinatal mortality•10 x cerebral necrotic lesions

•1% of monozygotic twins are monoamnionic

•Perinatal mortality rate of 30-50%, largely relates to a risk of intrauterine death before 32 weeks

•Cord entanglement

Twin-Twin Transfusion Syndrome

•Incidence : 4 - 20% of MC twins

•It is characterised by an imbalance of blood flowbetween the twins

•15 - 20% of perinatal deaths

•Untreated, perinatal loss rates in the mid-trimester(80 - 100%)

Large volume amnioreduction

Amniotic Septostomy

Fetoscopic Laser Ablation

DELIVERY BY CAESAREAN SECTION

AT 34 WEEKS

Conjoined twins or Siamese twins

•Anterior (thoracopagus)

•Posterior (pygopagus)

•Cephalic (craniopagus)

•Caudal (ischiopagus)

Single intrauterine demise

•2-6% of twins pregnancies

•Up to 25% in MC twin pregnancy

• Perinatal morbidity and mortality of the surviving co-twin

- 19% perinatal death- 24% having serious long term sequelae

Treatment options

•No optimal management

•Prompt delivery -Iatrogenic prematurity risks

•Conservative treatment -Subsequent handicaps

•Intrauterine interventions

High order multiples

•Perinatal risk increases exponentially with increasing number of fetuses

•Multifetal pregnancy reduction (MFPR) at 10 to 12weeks should be recommended for quadruplets andhigher multiples

•The situation with triplets is more controversial