This document discusses multiple pregnancies, including twins and higher order multiples. It covers the types of twins (dizygotic and monozygotic), risk factors, complications specific to monozygotic twins, maternal physiological adaptations, diagnosis, antenatal care including fetal surveillance and method of delivery. Outcomes are outlined such as the perinatal mortality rate being 5 times higher for twins compared to singletons, and congenital anomalies accounting for 15% of twin pregnancy mortality. Intrauterine death of one twin increases other risks, and higher order multiples have very high mortality risks due to extreme prematurity.

1. Ghadeer Al-Shaikh, MD, FRCSC
Assistant Professor & Consultant
Obstetrics & Gynecology
Urogynecology & Pelvic Reconstructive Surgery
Department of Obstetrics & Gynecology
College of Medicine
King Saud University

2. MULTIPLE PREGNANCY
 Twin pregnancy represents 2 to 3% of all pregnancies.
 The PNMR is 5 times that of singleton

4. DIZYGOTIC TWINS
 Most 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.

5. Factors affecting it’s incidence
 Induction 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.

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

7. 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.

8. MONOZYGOTIC TWINS
 70% are diamniotic monochorionic.
 30% are diamniotic dichorionic.

9. Determination of zygosity
 Very important as most of the complications occur in
monochorionic monozygotic twins.

10. During pregnancy by USS
 Very 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.

13.  Different sex indicates dizygotic twins.
 Separate placentas indicates dizygotic twins

14. Determination of zygozity After Birth
 By examination of the MEMBRANE, PLACENTA,SEX ,
BLOOD group .
 Examination of the newborn DNA and HLA may be
needed in few cases.

15. Complications of Multiple Gestation
 Anemia
 Hydramnios
 Preeclampsia
 Preterm labour
 Postpartum hemorrhage
 Cesarean delivery
 Malpresentation
 Placenta previa
 Abruptio placentae
 Premature rupture of the
membranes
 Prematurity
 Umbilical cord prolapse
 Intrauterine growth
restriction
 Congenital anomalies
Maternal Fetal

16. 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.

17. 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.

18. Possible methods of treatment:
 Repeated amniocentesis from recipient.
 Indomethacin.
 Fetoscopy and laser ablation of communicating
vessels.

20. 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)

21. Maternal Physiological Adaptation
Increase 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.

22. 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.

23. 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.

24. Antenatal Care
AIM
 Prolongation of gestation age, increase fetal weight.
 Improve PNM and morbidity.
 Decrease incidence of maternal complications.

25. Antenatal Care
Follow Up
 Every two weeks.
 Iron and folic acid to avoid anemia.
 Assess cervical length and competency.

26. Antenatal Care
Fetal 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.

27. Method Of Delivery
Vertex- Vertex (50%)
 Vaginal delivery.
Vertex- Breech (20%)
Vaginal delivery by senior obstetrician

30. Method Of Delivery
Breech- Vertex( 20%)
 Safer to deliver by CS to avoid the rare interlocking
twins( 1:1000 twins ).
Breech-Breech( 10%)
 Usually by CS.

31. Method Of Delivery in Monochorionic Twins
 C/S

32. 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.

33. Perinatal Outcome
 Congenital 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.

34. 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

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

36. HIGH RANK MULTIPLE GESTATION
 Spontaneous 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

38. Thank You!!!