Fetal Growth Assessment Flashcards
what is at term?
38-42
What is preterm?
before 38 weeks
what is post term?
later than 42 weeks
What is IUGR?
intrauterine growth restriction (retardation)
decreased rate of fetal growth
fetal weight at or below 10%
What are the risks with IUGR?
antepartum death
perinatal asphyxia
neonatal morbidity
later developmental problems
mortality increases six to ten fold
What is SGA?
small for gestational age
below 10th percentile without reference to cause
IUGR is a subset of the SGA as a result of a pathologic process
How are SGA and IUGR different?
IUGR has a pathological reason behind it
What are the causes of IUGR?
DM - diabetes mellitus
SLE - systemic lupus erythematosus
HTN
placental-uteroplacental insufficency UPI
fetal/genetic abnormalitites
What are the maternal factors for IUGR?
poor maternal nutrition
poor pregnancy weight gain
maternal use of drugs alcohol or smoking
previous history of fetus with IUGR
significant maternal hypertension
presence of uterine anomaly
significant placental hemorrhage
placental insufficiency
What are the placental factors with IUGR?
extensive primary placental infarctions»_space;lead to UPI
maternal and placental factors lead to asymmetric IUGR*
what are associated with symmetric IUGR?
primary fetal developmental anomalies (genetic/or chromosomal)
chronic fetal infections (TORCH)
usually result in first trimester*
How does the fetus appear with a symmetric IUGR?
proportionally small in all physical parameters due to earlier impact
may appear Sonographically BEFORE 20 WEEKS
approx 20-30%
What are the factors for asymmetric IUGR?
cause related to maternal disease states or later developing placental causes
last 8-10 weeks of pregnancy
Typically develops AFTER 24 weeks
more common than symmetric
what are the maternal reasons behind asymmetric IUGR?
maternal disease:
diabetes
chronic HTN
cardiac or renal
abruptio placentae
multiple pregnancy
smoking
poor weight gain
drug usage
uterine anomaly
How do you get an accurate fetal age?
last menstrual period
first tri US
standard BPD, AC, HC, FL
What are the clinical observations for IUGR?
decrease fundal height
decreased fetal motion
What ratio is most important when assessing for IUGR?
HC/AC ratio
What are the sonographic parameters for IUGR?
HC:
symmetric - less than 3rd% for age
asymmetric - normal growth until very late
IUGR affects fetal liver
AC - single MOST SENSITIVE indicator of IUGR
What are you assessing for the biophysical profile?
fetal breathing
fetal body movement
metal muscle tone
AFI
fetal heart rate changes (assessed with NST - not done in US)
When does fetal breathing become regular?
20-21 weeks
When does fetal heart rate change in response to fetal movement?
12-14 weeks
CNS (central nervous system) matures when?
slide 21
what is acute hypoxia?
decrease in breathing, moving and heart rate activity
What is severe acute hypoxia?
absence of movement/tone
What is chronic hypoxia?
result of UPI
Oligo and decreased movement is common
What is the time for the BPP?
timed 30 minutes
Finish slide 23
How many fetal gross movements do you need to see?
three
definite extremity or trunk movements in 30 minutes for 2 points
fewer than three scores 0
What is needed for the AFI in the BPP?
slide 27
What is fetal tone?
slide 28
What is NST?
slide 29
What is quantitative umbilical cord doppler?
measure velocity
what is qualitative umbilical cord doppler?
the characteristics of the waveform
if the S/D ratio is more than 3.0 in umbilical artery after 30 weeks what do you suspect?
serious abnormality
NEVER have absent or reversed diastolic flow
is it normal for there to be diastolic notching after 22 weeks in the uterine artery?
no
an S/D of more than 2.6 is abnormal
slide 34
What is macrosomia?
birth weight is more than 4000grams
above 90th percentile
When do you typically find a macrosomic baby?
multiparous
> 35 yrs old
pre-pregnancy weight > 154 lb
finish slide 41
What is a common reason for macrocomia?
maternal diabetes mellitus
What are the syndromes in which fetal increase in size with or
finish slide 43
what are the two types of macrosomia?
mechanical
metabolic
finish slide
45
