Describes biophysical profile categories and score

1. Joyce Mwatonoka, MD5
The University of Dodoma
April 2017

2.  Introduction
 Parameters of biophysical profile
 Scoring and interpretation
 Other tests
 References

3.  It is a technique employed to forecast fetal
well-being focus on fetal biophysical findings
that include heart rate, movement, breathing,
and amniotic fluid production
 It contains 5 parameters; nonstress test (NST),
fetal breathing, fetal movements, muscle tone
and amniotic fluid volume

4.  Modified Biophysical Profile consists of NST
and ultrasonographically determined amniotic
fluid index (AFI)
 Modified BPP is considered abnormal (non
reassuring) when the NST is non-reactive
and/or the AFI is < 5

5.  Currently, nonstress test is the most widely
used primary testing method for assessment
of fetal well-being
 It describes FHR acceleration in response to
fetal movement as a sign of fetal health
 Involved the use of Doppler-detected FHR
acceleration coincident with fetal movements
perceived by the mother

6.  As hypoxia develops, these fetal heart rate
accelerations diminish
 Normal results; two or more accelerations
that peak at 15 bpm or more above baseline,
each lasting 15 seconds or more, and all
occurring within 20 minutes of beginning the
test

7.  A 40-minute or longer tracing to account for
fetal sleep cycles should be performed before
concluding that there was insufficient fetal
reactivity
 Studies show 1 acceleration was just as
reliable as 2 in predicting healthy fetal status
 Also accelerations with or without fetal
movements may be accepted

8. Abnormal results;
1) baseline oscillation of less than 5 bpm,
2) absent accelerations, and
3) late decelerations with spontaneous uterine
contractions

9. Abnormal results were associated consistently
with evidence of uteroplacental pathology eg;
 IUGR
 placental infarction
 Oligohydramnios
 fetal acidemia and
 meconium

10.  Interval between testing set at 7 days; but
more frequent testing is advocated for women
with post-term pregnancy, multifetal
gestation, type 1 diabetes mellitus, IUGR, or
gestational hypertension
 In these circumstances, twice-weekly tests,
with additional testing is advised

11.  Passive unstimulated fetal activity commences
as early as 7 weeks’ gestation and becomes
more sophisticated and coordinated by the
end of pregnancy
 Between 20 and 30 weeks, general body
movements become organized, and by 36
weeks behavioral states are established in
most normal fetuses

12. Four fetal behavioral states described:
 State 1F is a quiescent state; quiet sleep, with
a narrow oscillatory bandwidth of the FHR
 State 2F includes frequent gross body
movements, continuous eye movements, and
wider oscillation of the FHR. It is analogous to
REM or active sleep in the neonate

13.  State 3F includes continuous eye movements
in the absence of body movements and no
heart rate accelerations
 State 4F is one of vigorous body movement
with continuous eye movements and heart
rate accelerations. This state corresponds to
the awake state in newborns

14.  Fetuses spend most of their time in states 1F
and 2F (>75% at 38 weeks)
 Mean length of the quiet or inactive state for
term fetuses was 23 minutes (up to 75min)

15.  Amnionic fluid volume is another important
determinant of fetal activity
 Perception of 10 fetal movements in up to 2
hours is considered normal

16. Two types of respiratory movements;
 The first are gasps or sighs, which occurred at
a frequency of 1 to 4 per minute
 The second, irregular bursts of breathing,
occurred at rates up to 240 cycles per minute
 These latter rapid respiratory movements
were associated with REM sleep

17.  Diurnal variation, because breathing
substantively diminishes during the night
 But, increases somewhat following maternal
meals
 Total absence of breathing was observed in
some normal fetuses for up to 122 minutes,
indicating fetal evaluation to diagnose absent
respiratory motion may require long periods
of observation

18.  Decreased uteroplacental perfusion may lead
to diminished fetal renal blood flow,
decreased urine production, and ultimately,
oligohydramnios
 Amniotic fluid index < 5 cm or a maximum
deepest vertical pocket < 2 cm are acceptable
criteria for diagnosis of oligohydramnios

19.  Normal; ≥ 1 pocket measuring 2 cm in two
perpendicular planes (2 × 2 cm pocket)

20.  Normal; ≥ 1 episode of extension (limb or
trunk) with return of flexion

22.  8-10; no fetal asphyxia, repeat weekly
 6; suspected chronic asphyxia, if >36 weeks
deliver, if less repeat test in 4-6hours
 4 and below; strongly suspect asphyxia, if
>36weeks deliver, if not repeat after 4-6 hours
for 120minutes, persistent score <5 deliver
regardless of GA

24.  Formerly known as oxytocin challenge test
 Intravenous diluted oxytocin was used to
stimulate contractions, and the FHR response
was recorded
 The criterion for a positive test result, that is,
an abnormal result, was uniform repetitive
late fetal heart rate decelerations (which
could be the result of uteroplacental
insufficiency)

25.  Nipple stimulation to induce uterine
contractions is usually successful for
contraction stress testing
 2-minute nipple stimulation ideally will induce
a pattern of 3 contractions per 10 minutes, if
not after 5 minutes, retry, if unsuccessful,
diluted oxytocin

26.  Loud external sounds have been used to
startle the fetus and thereby provoke heart
rate acceleration
 An acoustic stimulator is positioned on the
maternal abdomen, and a stimulus of 1 to 2
seconds is applied
 A positive response is defined as the rapid
appearance of a qualifying acceleration
following stimulation

27.  Arterial Doppler waveforms are helpful to
assess the downstream vascular resistance
 Three fetal vascular circuits; umbilical artery,
middle cerebral artery, and ductus venosus
can be assessed to determine fetal health
 Maternal uterine artery Doppler velocimetry
has also been evaluated to predict placental
dysfunction

28.  Venous Doppler parameter provide
information about cardiac forward function
(cardiac compliance, contractility and after
load)
 Fetuses with abnormal cardiac function show
pulsatile flow in the umbilical vein (UV)
 Normal UV flow is monophasic

29.  Williams Obstetrics 24e 2014
 DC Dutta’s Text Book of Obstetrics 7E REVISED
2014