This document discusses multiple gestation pregnancies, specifically twins. It notes that twins make up about 99% of multiple gestations and are either identical (monozygotic) or non-identical (dizygotic). Identical twins share a single placenta while non-identical twins have separate placentas. Multiple gestations carry higher risks than singletons such as preterm birth and fetal growth restriction. Complications are more common in monochorionic twins due to the risk of twin-to-twin transfusion syndrome and cord accidents. Care involves monitoring fetal growth and well-being as well as managing any complications that may arise.

1. +
Multiple
Gestation
Prepared by:
Jumana Haider
N. H.

2. +
 Multiple pregnancies consists of ≥2 fetuses.
 Twins make up ~99%
 Pregnancies of ≥3 fetuses are referred to as “Higher Multiples”.

7. +
Classification
 Number of fetuses: Twins, triplets, quadruplets, etc.
 Number of fertilized eggs: Zygosity
 Number of placentae: Chorionicity
 Number of amniotic cavities: Amnionicity

8. +
 Non-identical/fraternal twins are dizygotic
 Fertilization of 2 separate eggs.
 Either same- or different sex pairings.
 Always have 2 functionally separate placetae

9. +
 Identical twins are monozygotic
 Fertilization of a single egg
 Always same-sex pairings.
 Mono- or di- chorionic

10. +
 In dichorionic twins, the 2 separate placentae my anatomically
fuse together and appear as a single placental mass.

11. +
Key point
 Not all dichorionic pregnancies are dizygotic.
 All monochorionic pregnancies and monozygotic.

12. +
Risk Factors
 Assisted reproduction techniques
 IVF
 Ovulation induction
 Increased maternal age
 High parity
 Black race
 Maternal family history

13. +
 Type of monozygotic twin depends on how long after
contraception the splitting occurs.

15. +
Physiological changes

16. +
I. Maternal
 All the physiological changes will be exaggerated.
 There will be an increase in:
 Cardiac output
 Volume expansion
 Relative hemodilution
 Diaphragmatic splinting
 Weight gain
 Lordosis

17. +
II. Fetal
 Monochorionic placentae have the unique ability to develop
vascular connections between the two fetal circulations.
 These anastomoses carry the potential for complications.

18. +
Complications Relevant to
Twin Pregnancy

19. +
 Miscarriages and severe preterm delivery
 Death of one fetus in a twin pregnancy
 Fetal Growth Restriction
 Fetal Abnormalities
 Chromosomal defects in twinning

20. +
Complications Unique to
Monochrionic Twinning

21. +
 Twin-to-twin transfusion syndrome (15%)
 Growth-restricted fetus (donor)  Hypovolaemic and oligouric
 oligohydramnios
 Recepient  hypervolaemic  polyuria polyhydramnios

22. +
 >90% TTTS complicated pregnancies end in miscarriage or
very preterm delivery.
 With treatment, one or both babies survive (~70% of
pregnancies).

23. +
Complications Unique to
Monoamniotic Twinning

24. +
 Increased cord accidents, mainly through their universal cord
entanglement.
 This could be acute, fatal and unpredictable.
 Many clinicians support elective CS at 32-34 weeks.

25. +
Differential diagnosis
 Polyhydramnios
 Uterine fibroids
 Urinary retention
 Ovarian masses

27. +
Determination of choronicity
 In Monochorionic twins the inter twin membrane joins the
uterine wall in a T shape.

28. +
 In dichorionic twins there is a V shape extension of placental
tissue into the base of the intertwin membrane (Lambda or twin
peak sign).

29. +
Antenatal Management
 Screening for common conditions in twin pregnancy ,such as
hypertension and gestational diabetes.
 Increase supplementation of iron and folic acid.

30. +
Screening for fetal abnormalities
 Screening of trisomy 21
 Procedures such as amniocentesis and chorionic villus
sampling can be done
 Screening for structural anomalies

33. +
Monitoring fetal growth and well
being
 Measuring symphysis fundal height
 Presence of fetal movements
 Doppler investigations
 CTG

35. +
Threatened preterm labor
Start steroid therapy
Screen for GBS and give antibiotic
therapy if needed

36. +
Intrapartum Management
Preterm birth
Cord prolapse
Abnormal presentation
Post-partum hemorrhage

37. +
Preparation:
Start CTG for fetal monitoring
Keep oxytocin ready in case of PPH
Give appropriate analgesia

38. +
Delivery
 Allow vaginal delivery of the first twin
 Palpate the abdomen to asses the lie of the
second twin
 Then wait for the delivery of the second twin
I. Vaginal delivery of vertex - vertex:

40. +
 If the second twin is breech, then external
cephalic version has to be done ,and then the
delivery can proceed successfully
II. Delivery of vertex non vertex:

42. +
 Cesarean section is done immediately
III. Non vertex first twin:

43. Questions?!