Fetal surveillance

1. PRENATAL DIAGNOSIS
&
FETAL SURVEILLANCE
DR IO ADEBARA MPH, FMCOG
CONSULTANT DEPT OF OBGYN FETH IDO
ASSOCIATE LECTURER DEPT OF OBGYN
ABUAD

2. INTRODUCTION
DEFINITION
PD is the science of identifying structural and
functional abnormalities in the developing
fetus through invasive and non-invasive
techniques.
SIGNIFICANCE
 About 2-3% of all live born infants have an
abnormality.
 These anomalies account for majority of
miscarriages and perinatal deaths.
 More than a quarter of all paediatric hospital
admissions result from genetic disorders.

3. OBJECTIVES
 Primary objective is to prevent fetal
death
 Ensure satisfactory fetal growth and well
being
 Identify adverse factors that could affect
fetal well being
 Treat or modify any identified risk
 Determine the optimal time, mode and
place of delivery
 Plan the postnatal management.

4. ETHICAL / LEGAL CONSIDERATIONS
 The pregnant woman has an ethical
obligation to accept fetal therapy for a
viable fetus:
◦ If treatment to prevent a serious disease or
handicap would benefit or save the life of the
fetus.
◦ If mortality or injury to the fetus is unlikely.
◦ If mortality or morbidity in the mother is unlikely.
INTRODUCTION

5. Screening tests
 Tests that do not provide a diagnosis but
rather identify individuals with risk high
enough to benefit from a definitive
diagnostic test.
 Prenatal screening tests should meet
criteria generally accepted for other types of
screening tests:
1. The disease is well defined and serious.
2. Treatment or prevention is available
3. The screening test is cost effective and reliable.
4. The subsequent diagnostic test is reliable.

7. Indications
1. GENERAL RISKS
◦ Maternal age>35yrs
◦ Abnormal MSFAP
◦ Abnormal triple screening
results
3. Certain ethnic groups
◦ Blacks, Indians
◦ Jews
◦ mediterrenean
2. SPECIFIC RISKS
 Parents with congenital
abnormality
 Previous Hx
 Balanced chromosomal
translocation
 Mother with X-linked abnormal
gene e.g Duchenne MD
 Both parents with same
recessive abnormal gene (e.g.
sickling gene)
 Recurrent miscarriages or
stillbirth
 Maternal disease e.g. DM
 Chronic alcohol or drug
consumption in mother
 Maternal rubella infection
 Teratogen exposure
 Consangunity

8. TECHNIQUES FOR PRENATAL
DIAGNOSIS
Non Invasive Invasive
1. Maternal Serum Testing
2. Ultrasonography
3. Foetal
Echochardiography
4. Fetal Cells from
Maternal Blood
5. Fetal MRI
1. Chorionic Villus
Sampling
2. Amniocentesis
3. Percutaneuos Umbilical
Blood Sampling
4. Foetoscopy /
Endoscopy
5. Foetal Tissue Sampling

9. Fetal therapy
CONDITION TREATMENT
Erythroblastosis fetalis
Pulmonary immaturity
Fetal supraventricular tachycardia
Fetal hypothyroidism
Congenital adrenal hyperplasia
Sacrococcygeal teratoma
Urinary tract obstruction
Diaphragmatic hernia
hydrocephalus

10. FETAL SURVEILLANCE
Fetal surveillance encompasses all
measures taken in pregnancy to determine
fetal well being up to the delivery of a healthy
baby.
AIMS:
 Identify fetuses at risk of intrauterine death
 Identify fetuses at risk of neurologic
impairment and long term disability
 Ensure satisfactory fetal growth and
development
 Identify factors that could adversely affect
fetal outcome
 Proffer solutions to identified risk factors

11. Indications
 Routine for all women
 Maternal age
 Medical disorders in
pregnancy
◦ Hemoglobinopathy
◦ Cyanotic heart disease
◦ Chronic Hypertension
◦ DM
◦ Chronic renal disease
◦ Hyperthyroidism
◦ SLE
◦ Anti-phospholipid
syndrome
 PIH
 Decreased fetal
movement
 Oligo/polyhydramnio
s
 IUGR
 Post term gestation
 Multiple gestation
 Rh-isoimmunisation
 Premature ROM
 Previous
unexplained fetal
demise
Maternal-related Pregnancy-related

12. .
ANTEPARTUM
1. Maternal history &
routine ANC tests
2. Serial SFH
measurements
3. Fetal heart rate counts
4. Fetal movement count
5. Serial USS to detect
IUGR
6. Amniotic fluid index
7. Non stress test
8. Contraction stress test
9. Fetal biophysical profile
10. Modified biophysical
profile (NST+AFI)
11. Fetal doppler studies
INTRAPARTUM
1. Non invasive
◦ Fetal heart rate
count
◦ Liquor colour
◦ Cardiotocograph
2. Invasive
• Internal CTG
• Fetal blood
sampling
• Fetal scalp
electrodes

13. Non stress test
 Done on a non-labouring woman
 Assesses FHR in response to fetal
movement
 Two accelerations i.e. rise in FHR of
15beats/min above base line for at
least 15 seconds before returning to
baseline is expected in 20min
 Reported as reactive or non-reactive

14. Contraction stress test
 Designed to assess ability of a fetus to
survive stress of labour
 Three Contractions in 10min, each lasting
at least 40 sec are stimulated.
 Normal fetus respond to hypoxia by
deceleration then immediate acceleration
 Contra indicated in situation in which
labour is not desired.
 May provoke preterm labour
 Results reported as negative, positive or
equivocal.

15. Biophysical profile
VARIABLE NORMAL ABNORMAL
Fetal breathing
movementt.
>1 lasting 30sec in 30
min
Absent or <1
Gross body
movement.
>3 body movt <3
Fetal tone > 1 flexion-extension,
open –close hand
cycle
Absent or slow
NST > 2 acceleration with
fetal movt
<2 acceleration or 1 +
deceleration
Amniotic fluid vol >1 pool of 1*1 None or less than
1*1cm pool

16. Doppler flow velocimetry
Rationale:
 Pulsatile flow in umbilical artery is an
of indication feto-maternal status
 Decrease in placental function will
result in Increased resistance
 Evidenced in fetal diastolic flow
(reduced, absent or reversal)
 More reliable than other commonly
used methods

17. Vessels
 Fetal middle cerebral artery== fetal
anaemia
 Fetal ductus venosus=== IUGR
 Fetal umbilical artery== IUGR
 Maternal uterine artery=== predicts
PE, IUGR

18. Fetomaternal Surveillance in Labour – Use of
partograph
Graphical records of events of labour.
Components of the partograph:
Labour progress
Maternal condition
Fetal condition
Note concept of active Mgt of labour:
Monitoring labour –alert line
-action line
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19. Fetal Heart Auscultation :Pinard’s Fetal
Stethoscope/Sonicaid
Easy to use, widely available
Suitable for low-risk pregnancies
Should ideally be used before, during, and
after uterine contractions
Drawback –
Cannot be used for continuous fetal
monitoring
Subject to significant inter and intra observer
variations
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20. Electronic Fetal Monitoring:
Methods and interpretations
Cardiotocography - CTG
1. Monitoring Fetal Heart Rate
2. Monitoring the Strength of Uterine
Contractions
Methods: 1. External CTG Monitoring
2. Internal CTG Monitoring
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21. CTG interpretation:
NORMAL:
 Baseline 110-150:
 variability : 10-25bpm
 Accelerations: 2 in 20min
 Decelerations : none
SUSPICIOUS
 Abnormal baseline
 No accelerations
 Reduced variability
 Variable deceleration
ABNORMAL
 No accelerations
 Abnormal baseline
 Abnormal variability
 Repetitive late deceleration
 Variable deceleration

22. Fetal Blood Sampling
Involves collection of fetal scalp (buttock) blood
sample after rupture of fetal membranes
(using an amnioscope) and determination of
fetal pH.
pH<7.2 (first stage) or <7.15 (second stage)
considered indication for immediate delivery.
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