Chapter 32: Fetal Growth Restriction Flashcards
chemical substance that is the subject of analysis
analyte
abnormal chromosome number
aneuploidy
combined observation of four separate fetal biophysical variables (fetal breathing, fetal body movement, fetal tone, amniotic fluid index? obtained via ultrasound. This can be done with or without NST
Biophysical profile
Noninvasive ultrasound test that assesses blood flow velocity profiles from which indices of impedance can be obtained or flow volumes can be calculated.
Doppler velocitremy
estimated fetal weight or abdominal circumference less than the 10th percentile for gestational age
fetal growth restriction (FGR) or IUGR
low oxygen blood level
hypoxemia
without known cause
idiopathic
birth weight below 2500 g or 5 lbs 8 ox
low birth weight
incidence of a specific disease in a population for a set amount of time
morbidity
frequency of deaths in a specific population
mortality
method of assessing fetal well-being by observing fetal heart rate accelerations
nonstress test
low amniotic fluid levels
oligohydramnios
condition characterized by the discrepancy between the chromosomal makeup of the fetus and placenta
placental mosaicism
hypertension, and protein in the urine, occurring during second half of pregnancy
preeclampsia
the proportion of people who test positive for a disease who actually have the disease
sensitivity
diagnosis used to describe an infant that is smaller than expected for the gestational age
small for gestational age
having three copies of a specific chromosome
trisomy
A newborn’s _____ closely relates to risks for early death and long-term morbidity
birth weight
Stillbirth rates _____ as fetal weight increases.
decrease
premature infant
37 weeks or earlier
LBW infants are likely a result of:
fetal growth restriction
a sonographic estimated fetal weight or abdominal circumference that is less than the 10th percentile for gestational age
fetal growth restriction
newborns identifying a neonate with a birth weight less than 2500 g or 5 lbs 8 oz
small for gestational age
Growth restricted fetuses are at an increased risk of _____, ______, and ______.
intrauterine demise
neonatal morbidity
neonatal death
the interval between the onset of fetal viability and the end of the neonatal period
perinatal period
onset of fetal viability
24 weeks
end of neonatal period
28 days after delivery
second leading cause of perinatal mortality and morbidity
FGR
leading cause of perinatal mortality and morbidity
preterm delivery
A fetus with _______ has a fivefold to tenfold increase in risk for perinatal mortality
poor intrauterine growth
In FGR the overall general risk of fetal death
1.5%
risk of fetal death when the fetal weight is less than the 5th percentile
2.5%
__% of stillborn infants are SGA
26
FGR is a major group associated with stillbirth, accounting for up to __%
43
Meconium aspiration is increased with FGR infants because:
chronic hypoxia leading to meconium-stained liquor and aspiration
Hypoglycemia is increased with FGR infants because:
decreased glycogen stores, increased sensitivity to insulin, decreased adipose tissue, and decreased ability to oxidize free fatty acids and triglyceride effectively
Hypocalcemia is increased with FGR infants because:
decreased transfer of calcium in utero
Hypothermia is increased with FGR infants because:
proper care of temperature maintainence is not done
Polycythemia and other hematologic complications is increased with FGR because:
increased sythesis of erythropoietin seconday to chronic intrauterine hypoxia
Several studies suggest that the intact survival rates are less than 50% for fetuses with FGR at gestations under ____
28 weeks
Childhood increased risks for FGR infants
learning disabilities
behavioral problems
worse performance in school than term infants
Children affected by FGR have been found to have _____ blood pressure
higher
Most infants with FGR catch up on growth by:
18 years
Fetuses that are below the third percentile tend to have _____ and ____
lower weights
shorter statures
Adults who had FGR are at a much higher risk for ______, _______, and _____ later in life.
acquired heart disease
lipid abnormalities
diabetes
the in utero environment leads to the fetal origins of adult disease that persist into infancy, childhood, and adulthood
Barker hypothesis
Risk factors or etiologies of FGR
maternal
fetal
placental
Maternal medical conditions that affect blood circulation result in a:
decrease in uteroplacental blood flow
_______ in pregnancy is one of the leading causes of FGR
materal hypertension
Maternal age less than ___ years or greater than ___ years increase risk for FGR
16
35
Maternal tobacco use reduce birth weight by roughly ___-___g
150-200
leading cause of preventable FGR
tobacco use
___% of FGR cases can be credited to tobacco consumption
13
_____ is associated with the most severe growth deficits
preeclampsia
The most common chromosomal abnormalities that increase a fetus’ riskfor FGR are:
trisomy 13 Patau’s syndrome
trisomy 21 Down syndome
trisomy 18 Edwards syndrome
_____ is predominantly at risk for FGR, with 35% of these fetuses having FGR
trisomy 18
______ account for 5% of FGR cases.
congenital infections
______ is associated with the majority of cases of FGR.
placental insufficiency
Alterations in the ____ and _____ circulations are the most common placental conditions.
ureteroplacental
fetal placental
Incomplete trophoblastic invasion of the spiral arteries in the placental bed causes:
diminished maternal ureteroplacental blood flow
Reduced maternal uteroplacental function leads to:
inadequate supply of nutrients and oxygen to support normal aerobic growth
Villous damage to the placenta from under perfusion leads to:
increased placental resistance
_____ and ______ occur more frequently in FGR fetuses
placental abruption
placental infarcts
Two categories of FGR
symmetric
asymmetric
proportional reduction in all biometric measurements
symmetric growth restriction
Symmetric growth restriction accounts for __-__% of FGR infants
20
30
caused by a decrease in fetal cellular proliferation of all organs and is an impairment that occurs in the first or second trimester
symmetric growth restriction
occurs when an infant has a smaller abdominal size compared to head size
Asymmetric growth restriction
A head circumference to AC ratio of greater than the 95th percentile is usually used as the limit for:
asymmetric growth restriction
Asymmetric growth restriction is attributed to the ______
head sparing phenomenon
most common form of FGR occuring in 70-80% of FGR cases
asymmetric growth restriction
______ abnormalities have been suggested to be responsible for the changes in the concentration of serum placental products.
Trophoblastic invasion
In the absence of structural abnormalities or aneuploidy, an increased _______ has been linked with an increased risk of LBW
maternal AFP
A low level of ______ has been associated with LBW
pregnancy associated plasma protein A (PAPP-A)
distance from the top of the pubic symphysis to the top of the uterine fundus in centimeters
fundal height measurement
The fundal height measurement in centimeters should equal:
the gestational age in weeks
After 20 weeks, a difference greater than __cm in fundal height is suspicious for fetal growth restriction
3
It is still recommended by the ACOG that a fundal height measurement be done at every prenatal visit after ___ weeks
24
Obtaining measurement such as ___, ___, ____, and ____ can be used to calculate EFW
BPD
AC
HC
FL
The _____ formula is consistently better than other formulas
Hadlock
_______ in the second trimester is associated with an elevated risk of FGR
Echogenic bowel
The most accurate diagnosis of FCR is achieved by used:
multiple biometric and structural parameters
Growth assessments for FGR infants should be done ideally every ___ weeks
3
It is ____ for a fetus not to grow in a 2 week internal
normal
A nonstress test is also called
cadiotocography
measures the fetal heart rate accelerations over a specific time and period
nonstress test
most common method used to assess fetal well being
nonstress test
Deceletarations indicate:
compression of the umbilical cord
There is a direct relationship between hypoxemia and _____
decreased in FHR
occurs when there are two or more accelerations within 20 minutes of each other
normal or reactive nonstress test
defined by a lack of two or more accelerations detected in 40 minutes
abnormal or nonreactive nonstress test
noninvasive form of antenatal assessment of fetal well-being
biophysical profile
standard four biophysical features of an 8 point BPP
fetal movements
fetal tone
fetal breathing
estimation of amniotic fluid volume
A modified BPP uses ____ with ___
NST with AFV
A reassuring BPP scores is a __ or ___
8
10
A potentially concerning result from a BPP score is a score of ___
4 or less
A nonreactive result from a BPP could mean that the fetus is:
having trouble getting enough oxygen
A decrease in amniotic fluid is a result of a reduction in fetal blood and reduced fetal urine production as an effect from:
hypoxemia
foundation of management and follow up for FGR
pulsed-wave Doppler
Doppler abnormalities in the maternal uterine arteries, fetal UAs, and middle cerebral artery increase as FGR _____
worsen
When Doppler abnormalities present early in gestation, they progress more ____
rapidly
Doppler indices used in OB
S/D ratio
pulsatility index
resistive index
attained by measuring the peak frequency shift during systole and dividing by the frequency shift during diastole
S/D ratio
The difference between peak frequency shift in systole and diastole divided by the mean frequency
pulsatility index
the differency between the peak systolic frequency shift and the diastolic frequency shift divided by the frequency shift in systole
resistive index
most commonly interrogated fetal vessel
umbilical artery
primary tool for distinguishing patterns of progression
umbilical artery
most commonly used when evaluating the umbilical artery
S/D ratio
preferred technique for Doppler interrogation of the umbilical artery
free floating cord
Doppler waveforms should be taken in the absence of _____
fetal breathing
Normal arterial blood flow through the umbilical cord
sawtooth appearance with a low-resistance waveform and continuous forward flow
Severe FGR has been associated with ______ in the UA.
AEDF or reversed end-diastolic flow (REDF)
An increase in impedance in the UA implies the pregnancy is complicated by an underlying _____
placental insufficiency
Waveforms with a REDF flow in the UA are associated with obliteration of greater than __% of arteries in placental tertiary villi.
70
An AEDF or REDF in the UA has been linked with an increased risk of ______
perinatal mortality
The level of fetal hypoxemia correlates with:
severity of the UA Doppler abnormality
Normal MCA blood flow
high-impedance circulation with continuous forward flow
Waveforms from the poroximal portion of the MCA near the ______ have been shown to have the best reproducibility.
circle of Willia
When there is cerebrovascular dilation from hypoxia, there is a decrease in the ____, ___, and ___ of the MCA
S/D ratio
PI
RI
occurs when there is placental dysfunction that leads to fetal hypoxia, and blow flow resistance in the fetal brain decreases
fetal circulatory redistribution
Fetal circulatory redistribution is term
fetal “brain-sparing”
increased PI in the UA, reflecting reduced number of arterioles, infarction, and thrombosis in a fetus with FGR because of placental dysfunction
fetal “brain-sparing”
calculated as the ratio between the MCA PI and the UA PI
cerebroplacental ratio
incorporates data of both fetal response(MCA) and placental status (UA) in the prediction of unfavorable outcomes
cerebroplacental ratio
A CPR less than ____ is considered abnormal
1.08
The RI of the _____ decreased with increased gestation
uterine artery
shunts well-oxygenated umbilical venous blood directly to the heart
ductus venosus
reflects the physiological status of the right ventricle
ductus venosus
has the highest forward velocities in the venous system
ductus venosus
Normal DV waveforms
triphasic
abnormal DV waveforms
decreased, absent, or reversed flow in the a-wave
Abnormal DV waveform represents:
myocardial impairment
increased ventricular and end-diastolic pressure from an increase in the right ventricular afterload
A DV with an absent or reversed a-wave increases the risk of perinatal mortality from 20% to ___%
50
The _____ transports oxygenated blood from the placenta to the liver.
umbilical vien
A normal UV Doppler waveform shows:
linear forward flow
Physiological pulsations in the UV occur until about __ weeks gestation
13
After 13 weeks of gestation, pulsations are associated with _____ or _____.
fetal breathing
fetal movement
Pulsations that are synchronous with the fetal cardiac cycle are indicative of ______
abnormal cardiac function
Abnormalities in the venous Doppler could indicate:
fetal deterioration
The direct measurement of AFV by dye dilution requires an:
amniocentesis
The most common normal range used for the MVP is __ to __ cm
2
8
a method for assessing amniotic fluid and is a sum of the deepest vertical pocket of fluid in all four quadrants of the uterus
AFI
An AFI between __ and __ cm in considered normal
5
25
Amniotic fluid evaluation is a measure of ______
chronic placental function
The AFV is determined by a balance between inflows from ______ and outflows of _____ and _____.
fetal urine
fetal swallowing
intramembranous water flow
Growth restriction because of placental insufficiency is a cause of ______ or _____.
oligohydramnios
low amniotic fluid
Early in the growth restricted fetus, there is placental vascular dysfunction leading to ______ and a ______
UA resistance
decrease in UA volume
Increased placental villous obliteration increases placental resistance, leading to an increase in the UA ____
S/D ratio
Preferential perfusion of the fetal brain leads to a decrease in the MCA _____.
S/D ratio
Increased hypoxemia, arterial resistance, and nutritional deprivation lead to ______
myocardial dysfunction
The _____ of the DV becomes absent or reversed as cardiac performance deteriorates.
a-wave
The first change in the BPP is usually _____ on the NST followed by______ changes.
FHR variability
fetal breathing
The purpose of management of FGR is to:
balance fetal and neonatal risks to optimize the timing of intervention
UTA Doppler screening at __-__ weeks may help recognize stillbirths at risk of antepartum stillbirth and preterm delivery
19
23
Growth restricted fetuses because of uteroplacental vascular insufficiency should warrant maternal surveillance for development of ______
severe preeclampsia
Maternal corticosteroids may be indicated if there is a significant possibility of delivery at or before ___ weeks of gestation
34
An FGR fetus is defined as a sonographic EFW less than the ___ percentile for gestational age
10th
FGR can be classified into two categories:
asymmetric or symmetric
Identification of growth restricted fetuses is done through sonographic ___, ____, and ____.
EFW
serum analytes
fundal height
The cause of FGR may be _____ or _____
idiopathic
multifactorial
Etiologies of FGR are numerous and can be divided into three groups:
maternal
fetal
placental
Conditions such as poor maternal weight gain, previous FGR infant, maternal complications, and inadequate pubic symphysis to fundal height growth are suggestive of:
FGR
Select the description that does not characterize FGR.
a. Growth 2 SD below the mean for gestational age
b. fetal lagging abdominal circumference
c. An EFW <10th percentile
d. Macrosomia
d
A cause of intrauterine growth restriction is:
a. maternal hypertension
b. incorrect LMP
c. unexpected ovulation date
d. small parents
a
FGR affects the fetal blood flow by:
redistributing it to the fetal brain
FGR can cause poor health for the fetus into adulthood. They include all except:
a. hypertension
b. diabetes
c. anorexia
d. obesity
c
Preeclampsia:
a. is a condition where elevated protein is discovered in the maternal urine
b. is a condition of low blood pressure
c. causes maternal hydronephrosis owing to elevated urinary protein
d. causes fetal weight gain
a
A common cause of FGR is:
placental abnormalities
Herpes simplex virus, cytomegalovirus, rubella, and varicella zoster are ____ which relate to fetal growth restriction.
infectious conditions
Atypical growth pattern where the fetal AC lags the BPD, HC, and FL is known as:
asymmetric
Congenital malformation, drugs, and chromosomal abnormalities are usually responsible for:
symmetric FGR/IUGR
Identification of growth-restricted fetuses is done through sonographic EFW, fundal height, and:
serum analytes
BPP should only be performed when:
delivery of the fetus would be considered
A fundal height measurement difference of more than ___ cm less than expected after 20 weeks gestation is cause for suspicion of FGR.
3
If FGR is suspected, the ideal interval between growth evaluations is every:
3 weeks
The predictive error of ultrasound ____as the gestation increases.
increases
Common maternal treatments to increase growth in an FGR fetus includes all except:
a. nonimpact exercise
b. fish oil
c. aspirin
d. hyperoxygenation
a
A normal nonstress test displays:
a. fetal tone
b. two or more accelerations within 20 minutes
c. fetal breathing
d. amniotic fluid volume
b
Hypothermia, hematologic complications, and hypoglycemia are fetal conditions related to:
a. preeclampsia
b. FGR
c. acidemia
d. hypoxemia
b
FGR children, especially preterm, have an elevated risk of all except:
a. low blood pressure
b. behavioral problems
c. inferior school performace
d. neurological damage
a
Select the correct fetal category for a fetus displaying biometric parameters below 10% without a known cause, possibly relating to parental habitus and family history, small AC/BPD/HC/FL measurements, normal AFI, normal BPD/AC ratio, and normal placenta.
a. macrosomia
b. symmetrical FGR/IUGR
c. asymmetrical FGR/IUGR
d. SGA
d
The fetus with poor intrauterine growth has an _____ risk for perinatal mortality compared with the normal size fetus.
increased
Cord anomalies that increase the risk of FGR are ____ and ____
velamentous cord insertion
vasa previa
FGR infants usually achieve normal growth at the age of ____
18
Measurement of the largest pocket of fluid that is free of fetal parts or umbilical cord is called ____
MPV
Poor intrauterine growth and subsequent LBW are common features of many _____ abnormalites.
cardiovascular
The most common chromosomal abnormalities that increase a fetus’s risk for FGR are: ____ syndrome, _____ syndrome, and _____ syndrome.
Downs
Edwards
Pataus
There are over 50 published formulas for EFW. More recent publications show that the _____ formula is consistently better than other formulas
Hadlock
The cause of FGR/IUGR may be idiopathic or _____
multifactorial
A potentially concerning result from a BPP score is a score of ____ or less.
4
Maternal medical conditions that effect blood circulation results in a _____ in uteroplacental blood flow and can lead to FGR.
decrease
Maternal _____ in pregnancy is one of the leading causes of FGR.
hypertension
Preeclampsia occurs during the ____ half of pregnancy
second
In a normal fetus, the MCA is a ____ impedance circulation with continuous ____ flow.
high
forward
____ Doppler may help differentiate a consitutionally small fetus and a pathologic FGR fetus.
UA
Risk factors or etiologies of FGR can be divided into three groups; ____, _____, and ____
maternal
fetal
placental
Estimated fetal ____, sonographic biometry, Doppler flow, and _____ fluid changes assist in identification of growth restricted fetuses
weight
amniotic
Avoiding and cessation of smoking during pregnancy can increase fetal ____
weight
Increased hypoxemia, arterial resistance, and nutritional deprivation lead to _____ dysfunction
placental
Fetal circulatory redistribution when there is placental dysfunction is termed ______
placental insufficiency
Antenatal surveillance is done with four fetal growth assessments: ____, _____, _____, and _____.
fetal movements
fetal tone
fetal breathing
estimation of AFV
