2. What is fetal
monitoring?
Ante partum fetal surveillance
is the antenatal assessment of
fetal well-being to detect
hypoxia and prevent fetal
deaths
It is a method for the doctor to
check the health of the unborn
baby.
5. Assessment
of fetal
growth
Clinical
• Fundal height
• Maternal weight gain
Ultrasound
• Biparietal diameter
• Femur length
• Abdominal circumference
• Body proportions
• All these assessments are to be done serially
at weekly or bi-weekly intervals
6. Fetal
movements
A Fetal movement count-
60%
Cardiff count to 10 in 12 hrs.
<3movements in 12 hrs.-
movement alarm signal
>50% dec as compared to
previous day
10. Electronic
monitoring
B. Electronic fetal heart rate
monitoring
• Non-stress test (f. p. 40%)
• Contraction stress test (f. p.
15%)
• Fetal acoustic stimulation test (
specificity 77%, sensitivity 93%)
11. What are
the
different
kinds of
monitoring
A. Fetal Heart Rate
B. Uterine Activity
The heart beat IS monitored in 2
ways:
External monitoring: An elastic
belt and a receiver, called an
ultrasound transducer, is placed
on the belly. The receiver finds
the baby’s heart beat. .
Internal monitoring: A tiny device, called a spiral, is placed on
the baby’s head or buttocks. Wires are attached to the upper leg.
It is used only after membranes have ruptured.
Seldom done due to risk of infections.
•
12. Uterine activity
Contractions can be monitored in 2 ways:
a. outside the body: A small pressure-sensitive device, called a toco,
is placed on the belly. It is held in place with an elastic belt. The
device keeps a record of how long the contractions are and how
often they take place.
b. inside the body: A small, soft tube is placed inside the uterus beside
the baby. The tube measures how long the contractions are and
how often they take place. Seldom done due to infection risk
13. Instructions
before the
test
Patient can be asked to eat a
meal before having a non-stress
test,
The patient asked to not eat or
drink for 4 to 8 hours before the
contraction stress test.
Patient can be asked to stop
smoking for two hours before
the external monitoring test
14. How it is
done
• For a non-stress test, the
sensors are placed on the
belly. The patient is asked
to push a button on the
machine every time the
baby moves /uterus
contracts.
• The baby's heart rate is
recorded and compared to
the record of movement
(NST) or the contractions
(CST). This test usually
lasts about 30 minutes
15. Non stress test
EXTERNAL
MONITORING IS
USED FOR A
NON-STRESS
TEST, WHICH
RECORDS THE
BABY'S HEART
RATE WHILE THE
BABY IS MOVING
AND NOT
MOVING.
A NON STRESS
TEST CAN BE
INTERPRETED AS
A) REACTIVE OR
NORMAL
B) NON REACTIVE
OR ABNORMAL
C) EQUIVOCAL
OR SUSPICIOUS
16. Reactive NST
Normal or Reactive NST
• ( Features studied- Baseline FHR, beat to beat variability, spont. variability,
accelerations/decelerations)
• >2accelerations in 20 mins
• Sporadic deccel<40 bpm
• Action plan- repeat after one week as per clinical situation
• Chance of fetal demise 1-4/1000
19. Suspicious
or
equivocal
• No accelerations for >40 minutes
(extended NST)
• Alt baseline variability (5-10/>25bpm)
• Action plan
• Repeat in 6hrs and 24 hrs with
• FAST/BPP/AFI/Doppler
• FAST- Fetal acoustic stimulation test
• BPP-Biophysical profile
• AFI- Amniotic fluid index
20. Ominous or
Non
reactive
• Fetal heart rate <100 0r >180
• Severe decelerations
• Sinusoidal /silent pattern
• Action plan
• FAST/AFI/BPP/Doppler
• Consider delivery
26. What
Affects the
Test
Smoking cigarettes
drinking large amounts of caffeine ( strong coffee),
can falsely raise the baby's heart rate.
Extra noises ( heartbeat or stomach rumbling).
The baby is sleeping .
Certain sedatives or antihypertensive drugs
Problems with the placement of the external
monitoring device.
•The baby is moving a lot .
•Multiple pregnancy -twins or triplets.
•obesity
27. Risks of
electronic
monitoring
Risk of infection for the baby when internal
monitoring is done.
If the machine is having technical problems,
the machine may show that the baby is
healthy when he or she is in distress. ( rare).
Increased risk of cesarean section.
28. Precautions
in
interpreting
Fetal monitoring cannot predict every type of
problem, such as birth defects.
Continuous monitoring during labor is more likely
to be useful for high-risk pregnancies.
Intermittent fetal heart monitoring during labor is
as effective as continuous monitoring in low-risk
pregnancies.
The baby may move more if you eat or drink juice
before having a non-stress test. This may make the
test results more useful.
Sometimes other methods (such as ringing a bell
near the uterus) are used to cause changes in the
baby's heart rate.
29. Assessment
of fetal well
being
C: Ultrasonography
• Biophysical profile
• Doppler
• Biophysical profile (Manning score) (20mins)
• 5 Components – 1 fetal movements 2
• ``` 2 fetal flexed tone 2
• 3 fetal breathing 2
4 AFI >2 cms 2
• 5 NST reactive 2
• Score- normal -8-10 rpt. x 1wk,
• equivocal - 6 rpt x 4-6hrs
• ominous - <4 Deliver
• Modified Manning score – only the NST and AFI
35. Combined
first
trimester
screening
• recommended screening test done
during 1st trimester for trisomy 21
and trisomy 18
• incorporates nuchal translucency,
crown-lump length and maternal
age
• indication: done when the fetus has
a CRL of 45 to 84mm = 11W to
13W6D
• 2 parts:
(1) Biochemical analysis
(2) Ultrasound measurement of fetal nuchal
translucency
36. (1) Biochemical
analysis
• Blood collected ideally at 9 – 12W gestation for
biochemical analysis of
(1) Pregnancy associated Placental Protein-A (PAPP-A)
- highly expressed in 1st trimester trophoblasts
- participating in regulation of fetal growth
- levels in maternal serum increase throughout
pregnancy
(2) Free ßhCG
- synthesized by placental cells starting and
serves to maintain progesterone production
- the concentration begins to fall as the placenta
begins to produce steroid hormones
and the role of the corpus luteum in
maintaining pregnancy diminishes.
37. (2) Nuchal
translucency
• ultrasonographic sonolucency in
the posterior fetal neck
• gestational age dependent –
increase 15 – 20 % /week averagely
• Increased nuchal translucency of
greater than 3.5 mm is associated
with major congenital heart defects,
defects of the great vessels, fetal
malformations, dysplasia,
deformations, disruptions, and
genetic syndromes
38. Maternal serum screening
• screening test done during 2nd trimester for trisomy
21, 18 and neural tube defects
• Blood collected ideally 15 – 17W gestation for
biochemical analysis of
(1) Alpha fetoprotein
(2) Free ßhCG (or total hCG)
(3) Unconjugated estriol
(4) Inhibin A
Triple
screen Quad
screen
39. SCREENING
IN FIRST
AND
SECOND
TRIMESTER
Trimester Screening test Chromosomal
/structural
abnormalities
Substances
tested/
scanned
First Combined 1st
trimester
screening
Trisomy 21 and
trisomy 18
PAPP-A +
ßhCG + NT
Second Maternal
serum
screening
Trisomy 21,
trisomy 18 and
neural tube
defect
AFP + Free
ßhCG (or total
hCG) +
Unconjugated
estriol +
Inhibin A
Second Fetal
morphology
ultrasound
scan
Structural
abnormalities
40. conclusions
1.Electronic monitoring is here to stay
2. Training in the interpretation of the traces is essential
3.Routine continuous monitoring during labor is probably not cost effective in developing
countries
4. More studies are required for the intra-partum techniques before they are useful clinically
5. Ultrasound is now routinely recommended for each pregnancy at least once around 20
weeks.
