This document discusses multiple gestation pregnancies. It defines multiple gestation as a pregnancy with more than one fetus. The most common type is twins, which can be either monozygotic (identical) or dizygotic (fraternal). Multiple gestation pregnancies have higher risks of complications for both the mother and fetuses, including preterm birth and low birth weight. Close monitoring and interventions are needed to help support a healthy pregnancy outcome.

1. MULTIPLE GESTATION
Peggy Foster, RNC-OB, MSN
Sandy Warner RNC-OB, MSN

2. MULTIPLE GESTATION
 Definition—Pregnancy with more than 1
Fetus

3. Diagnosis of multiple gestation
 Size greater than dates
 Greatly elevated hCG levels
 Elevated alpha-fetoprotein (MSAFP)
 More than one audible heart beat
 U/S confirmation
 ART

4. Multiple Gestation
 Twins are most common form of multiples
 Monozygotic twins - 25%
 One sperm and one ova
 “identical”
 Can separate into more than 2 (identical triplets etc)
 Dizygotic twins are majority
Includes twins and higher order multiples
 “fraternal” or nonidentical
 Two ova and two sperm

5. Monozygotic vs. Dizygotic

6. Monozygotic vs. Dizygotic
 Amnion layer inside Chorion
 Dizygotic twins always have 2 amnions and 2
chorions
 Monozygotic twins can be
Mono Chorionic - Mono Amnionic
Mono Chorionic - Di Amnionic
OR Di Amnionic - Di Chorionic

8. Associated factors for dizygotic
twins
 ART (assisted reproductive technology)
 Age
 Ovarian follicicle stimulation
 Parity > 4
 Race—More common in Blacks—Less common
in Oriental populations
 Family history
 Coital frequency

9. Monozygotic twins occur
independently
 Cause is unclear

10. Monozygotic twins can be:
 Diamnionic/dichorionic—Occur<72 hours after
conception
 Monochorionic/diamnionic (MOST !!)—Occur 3-7
days after conception
 Conjoined twins >7 days after conception—
incomplete separation of developing embryonic
cell masses
 Monochorionic/monoamnionic –RARE !!

11. What we do know for Sure !!
 Different sex—always dizygous
 Different blood types—always dizygous
 If Monochorionic—always monozygous

12. Pregnancy Outcomes
 85% of multiple gestation mothers have
antepartal complications—compared with
only 32% of singleton pregnancies
 Perinatal morbidity and mortality is TWICE
that of singleton pregnancies—In these
women 4% of all maternal deaths are
related to vascular problems

13. Antepartum complications with
multiple gestation
 “Vanishing twins” may occur< 12 weeks
gestation
 “Fetal Papyraceous” > 12 weeks
 ↑ Spontaneous abortions
 ↑ Nausea and Vomiting
 ↑ Anemia
 ↑ uterine size and ↑ placental hormones—
explains minor discomforts of pregnancy—both
chemically and pressure related

14. Antepartum complications cont.
 ↑ PIH (20% of twin pregnancies)
 ↑ Hydraminous (Polyhydraminous)
 ↑ Blood Volume 500 ml > than singleton
 ↑ Uterine size causes ↑ Vena Cava Syndrome
 ↑ SOB
 ↑ Varicosities, VTEs, PEs
 Cholestasis

15. Ante & Intrapartum complications
cont.
 ↑ Edema
 ↑ Placenta Previa and ↑ Abruption
 ↑ Labor dystocia—secondarily to an over-
stretched myometrium-- ↑ PP Hemorrhage
 ↑ Preterm labor and deliveries (12 X that of
Singleton pregnancies)
 ↑ Cesarean rates
 ↑ Emotional adjustments and stress on family
relationships—both partner and siblings

16. Intrapartum complications
 Maternal  Fetal
 Acute fatty liver  Cord accidents
 Difficulty of fetal
 Malpresentation
monitoring
 Cardiac issues  Congenital anomalies
 ENVIRONMENTAL
 Availability of
necessary equipment
 Availability of
necessary personnel

17. Multiple tracing

18. Postpartum Complications
 PPH
 Pulmonary edema
 Lack of bonding/breastfeeding
 Feelings of being overwhelmed
 Delayed return to normal activity if long periods
of bed rest
 Fatigue
 Grief – acknowledging individuality

19. Risks to fetus (es)
 The 2 major causes of Neonatal M&M are:
PREMATURITY AND IUGR—50% of twins
weigh < 2500 gms at birth
 Monozygotic twins have 2-3 X PM&M rates as
Dizygotic
 ↑ Congenital Anomalies 2-3 X that of Singletons
and is more common in Monozygous twins
 Preterm Delivery is 5-10 X that of Singletons

20. Multiples Average Gestational
Age at Birth
 Singletons 40 weeks
 Twins 35 weeks
 Triplets 33 weeks
 Quadruplets 29 weeks
Prevention: Don’t do this 

21. TWIN TO TWIN
TRANSFUSION SYNDROME
 In Monozygotic twins the vessels may
develop vessel-vessel anastamosis
 Most common Artery-Vein
 Increase pressure of one vessel causes
transfusion to the lower pressure vessel
 Results in 1 twin (Recipient)--over-
perfused and other twin (Donor) under-
perfused

23. Twin-Twin Transfusion cont’d
 Recipient develops:
Polycythemia
Hypervolemia
Hypertension
Enlarged Heart
Increased Renal perfusion and excessive voiding
Polyhydraminous

24. Twin-Twin Transfusion cont’d
 Donor develops:
Hypovolemia
Anemia
Decreased Renal perfusion
Oligohydramnious
“Stuck twin”

25. Donor and Recipient

26. Common problems with Twins
 If twins share same sac
(Monoamnion/Monochorion) is ↑ chance
for Cord Entanglement
 Stillbirthrate ↑ to 50%
 These babies have ↑ developmental issues,
↓ IQ levels, and ↓ physical growth
 In all Multiple births there is ↑ Fetal
distress and ↑ Cesarean deliveries

27. Goals for Care of Multiples
 Promote Normal Development of all
fetuses
 Prevent Preterm Birth
 Decrease Fetal Trauma at Birth
 Support Mother’s needs throughout
Pregnancy

28. Interventions
 Nutrition: ↑ Calories 300 > Singleton
 ↑ weight gain to 40-60 #
 ↑ Folic acid
 ↑ Iron 60-100 mg/day
 ↑ Protein from 40 to 74 gms/day

29. Interventions cont.
 Monitor for Discordance—defined as >25%
difference in weight at birth—occurs in 9% of all
twins—When discordance occurs Neonatal
mortality ↑ 4X
 ↑ Prenatal Visits
 ↑ Teaching about Kick counts
 ↑ Teaching about Signs of PTL
 ↑ Teaching about Danger signs in pregnancy
(bleeding, Headaches, etc)

30. Interventions cont.
 Serial U/S to assess for Growth and
Development, IUGR, or discordance
 At 34 Weeks weekly NST’s
 ↑ Biophysical Profiles
 ↑ Bed rest ??? Benefit--controversial
 Arrange Pediatric/Neonatal Consult
 Discuss plans/options for delivery

31. Interventions cont.
VAGINAL DELIVERY if:
 Both are Vertex, if are Vtx/Breech/ or if
Vtx/Trans and both are > 1500 gms
 If fetuses are non-viable
CESAREAN DELIVERY if:
 1st fetus if Breech
 2nd twin is breech and weighs < 1500
 Unable to adequately monitor the 2nd
 Multiples > twins
 Mother requests

32. NURSING IMPLICATIONS
 Antepartum
 Emotional support of woman and significant
others
 Teaching
 Monitoring each fetus

33. NURSING IMPLICATIONS--IP
 INTRAPARTUM
 IV
 Type and Screen
 Monitoring
 Anesthesia always present and aware
 SCN/NICU/Neonatology aware
 Staffing to accommodate labor/Cesarean and
Neonatal outcomes

34. NURSING IMPLICATIONS--PP
Postpartum
Mom prone to PP hemorrhage
Many changes in Body systems back to Non-
pregnant state
Emotional changes—weary—
Needs ↑ Sleep
Humans are Monotropic—difficult to bond with 2
people at same time
Moms focus on concrete factors

35. NURSING PP cont’d
 May feel overwhelmed
 Feeding and Caring for 2 (+)
 Assistance with Breastfeeding
 Shock/Inadequacy/Guilt/Sadness

36. NURSING NEONATAL
 ↑ Birth Trauma
 ↑ Hyperbilirubinemia
 ↑ Respiratory problems
 Size Discrepancy
 Rx infections
 Effect of tocolytics given to mother
 ↑ Nutritional needs
 ↑Bonding needs of entire family
 ↑ Risks for Late Preterm infant

37. References
 AWHONN (2009) POEP
 Gilbert, E. S., (2011) 5th edition Manual of
High Risk Pregnancy and Delivery.
 Mattson, S. & Smith, J.E., (2011) 4th
edition Core Curriculum for Maternal-
Newborn Nursing.