Ghadeer Al-Shaikh, MD, FRCSCAssistant Professor & Consultant

Obstetrics & GynecologyUrogynecology & Pelvic Reconstructive

SurgeryDepartment of Obstetrics & Gynecology

College of MedicineKing Saud University

MULTIPLE PREGNANCYTwin pregnancy represents 2 to 3% of all

pregnancies.The PNMR is 5 times that of singleton

DIZYGOTIC TWINSMost common represents 2/3 of cases.Fertilization of more than one egg by more

than one sperm.Non identical ,may be of different sex.Two chorion and two amnion.Placenta may be separate or fused.

Factors affecting it’s incidenceInduction of ovulation, 10% with clomide and

30% with gonadotrophins.Increase maternal age ? Due to increase

gonadotrophins production.Increases with parity.Heredity usually on maternal side.Race; Nigeria 1:22 North America 1:90.

MONOZYGOTIC TWINSConstant incidence of 1:250 births.Not affected by heredity.Not related to induction of ovulation.Constitutes 1/3 of twins.

Results from division of fertilized egg:0-72 H. Diamniotic dichorionic.4-8 days Diamniotic monochor.9-12 days Monoamnio.monochor.>12 days Conjoined twins.

MONOZYGOTIC TWINS

70% are diamniotic monochorionic.

30% are diamniotic dichorionic.

Determination of zygosity

Very important as most of the complications occur in monochorionic monozygotic twins.

During pregnancy by USSVery accurate in the first trimester, two sacs,

presence of thick chorion between amniotic memb.

Less accurate in the second trimester the chorion become thin and fuse with the amniotic memb.

Different sex indicates dizygotic twins.

Separate placentas indicates dizygotic twins

Determination of zygozity After BirthBy examination of the MEMBRANE,

PLACENTA,SEX , BLOOD group .

Examination of the newborn DNA and HLA may be needed in few cases.

Complications of Multiple Gestation

AnemiaHydramniosPreeclampsiaPreterm labourPostpartum

hemorrhageCesarean delivery

MalpresentationPlacenta previaAbruptio placentaePremature rupture of

the membranesPrematurityUmbilical cord prolapseIntrauterine growth

restrictionCongenital anomalies

Maternal Fetal

Specific Complications in Monochorionic Twins

TWIN-TWIN transfusion.Results from vascular anastomoses between

twins vessels at the placenta.Usually arterio (donor) venous (recipient).Occurs in 10% of monochorionic twins.

TWIN-TWIN transfusion Chronic shunt occurs ,the donor bleeds into

the recipient so one is pale with oligohydramnios while the other is polycythemic with hydramnios.

If not treated death occurs in 80-100% of cases.

Possible methods of treatment:

Repeated amniocentesis from recipient.Indomethacin.Fetoscopy and laser ablation of

communicating vessels.

Other Complications in Monochorionic Twins: Congenital malformation. Twice that of

singleton.

Umbilical cord anomalies. In 3 – 4 %.

Conjoined twins. Rare 1:70000 deli varies. The majority are thoracopagus.

PNMR of monochorionic is 5 times that of dichorionic twins(120 VS 24/ 1000 births)

Maternal Physiological AdaptationIncrease blood volume and cardiac output.Increase demand for iron and folic acid.Maternal respiratory difficulty.Excess fluid retention and edema.Increase attacks of supine hypotension.

DIAGNOSIS OF MULTIPLE PREGNANCY+ve family history mainly on maternal side.+ve history of ovulation induction.Exaggerated symptoms of pregnancy.Marked edema of lower limb.Discrepancy between date and uterine size.Palpation of many fetal parts.

Auscultation of two fetal heart beats at two different sites with a difference of 10 beats

USS

Two sacs by 5 weeks by TV USS.Two embryos by 7 weeks by TV USS.

Antenatal Care AIM

Prolongation of gestation age, increase fetal weight.

Improve PNM and morbidity.Decrease incidence of maternal

complications.

Antenatal CareFollow Up

Every two weeks.Iron and folic acid to avoid anemia.Assess cervical length and competency.

Antenatal CareFetal Surveillance

Monthly USS from 24 weeks to assess fetal growth and weight.

A discordinate weight difference of >25% is abnormal (IUGR).

Weekly CTG from 36 weeks.

Method Of Delivery Vertex- Vertex (50%) Vaginal delivery.

Vertex- Breech (20%)Vaginal delivery by senior obstetrician

Method Of DeliveryBreech- Vertex( 20%)Safer to deliver by CS to avoid the rare

interlocking twins( 1:1000 twins ).

Breech-Breech( 10%)Usually by CS.

Method Of Delivery in Monochorionic Twins

C/S

Perinatal Outcome PNMR is 5 times that of singleton (30-

50/1000 births).RDS accounts for 50% 0f PNMR.2nd twin is

more affected.Birth trauma . 2ND twin is 4 times affected

than 1st .Incidence of SB is twice that of singleton.

Perinatal OutcomeCongenital anomalies is responsible for 15%

of PNMR.Cerebral hemorrhage and birth asphyxia are

responsible for 10% of PNMR.Cerebral palsy is 4 times that of singleton .50% of twins babies are borne with low

birth(<2500 gms.) from prematurity & IUGR.

INTRAUTERINE DEATH OF ONE TWIN Early in pregnancy usually no risk.

In 2nd or 3rd trimester: Increase risk of DIC . Increase risk of thrombosis in the a live

one The risk is much higher in monochorionic

than in dichorionic twins

The alive baby should be delivered by 32-34 weeks in monochorionic twins.

HIGH RANK MULTIPLE GESTATIONSpontaneous triplets 1:8000 births.Spontaneous quadruplets 1:700,000 births.The main risk is sever prematurity .CS is the usual and safe mode of delivary.High PNMR of 50-100 / 1000 births

Thank You!!!