Beckman Fetal Growth Abnormalities Flashcards
IUGR is fetus/infant whose weight is less than:
10th percentile (@ given gestational age)
Early in pregnancy, fetal growth occurs through ____ _____; later in pregnancy, through ____ _____
early: cellular hyperplasia (division)
later: cellular hypertrophy
why is late onset growth restriction possibly related to uteroplacental insufficiency?
Placenta maxes out growth by 37 weeks, after which there is a steady decline in SA and microinfarctions of vascular system
maternal infections ass. with IUGR
rubella, varicella, CMV
rate of growth restriction is ____x higher among babies born to moms who smoke during preg.
3-4x
meds ass. with IUGR
anticonvulsants, warfarin, folic acid antagonists
Inherent growth potential of the individual is determined: _____
genetically
T/F: Male and female fetuses are at same risk for IUGR
False…Females have higher risk
Screening test for IUGR
serial measurements of fundal height (but low Se and Sp)
between 20-36 weeks gestation, fundal height should increase:
1cm/week, consistent with gestational age in weeks
Significant discrepancy of ____cm may indicate IUGR and the need for an ______ exam
2 cm; Ultrasound (US)
if IUGR is suspected based on risk factors/clinical assessment, what’s the next step?
Ultrasound…assess fetal size and growth.
what are the four standard fetal measurements
- biparietal diameter
- head circumference
- abdominal circumference (AC)
- femur length
An _____ _____ within the normal range reliably excludes growth restriction
Abdominal Circumference (AC)
why perform amniocentesis if concerned about fetal growth?
assess lung maturity. Fetal karyotyping, viral cultures, and PCR can also be performed on fluid obstained by amnio.
The systolic-diastolic ratio in the umbilical artery indirectly measures:
Impedance/resistance downstream within placental vessels
Mechanisms of fetal surveillance (used to manage pregnancy with IUGR)
fetal movement counting, NST, BPP, Doppler
Neonatal mgmt of IUGR infants includes preparation for:
- Neonatal respiratory compromise
- hypoglycemia
- hypothermia
- hyperviscosity syndrome
What does hyperviscosity syndrome result from?
Fetus’s attempt to compensate for poor placental oxygen transfer by increasing the hematocrit to >65%
What complications can the polycythemia from hyperviscosity syndrome cause?
Multiorgan thrombosis, heart failure, hyperbilirubinemia
Is the prognosis ever good for a growth-restricted infant?
Yes, generally good if they survive the neonatal period
fetal macrosomia typically refers to an estimated weight >____g
4000-4500g
large for gestational age implies brith weighth of >____%
90th percentile for a given gestational age
macrosomia is based on______ alone and LGA is based on _____ and ______
M: Weight
LGA: Weight and gestational age
Fetal risk factors for LGA (3)
- Genetic potential
- Specific gene disorders
- Male sex
Maternal risk factors for infant LGA (5)
- hx of previous macrosomic preg
- metabolism
- body composition
- pregnancy wt gain
- parity
(ethinicity, gest. age>40wks, maternal age<17, and positive 50g glucose screen with eng result on 3hr GTT are also factors)
Is nulliparous or multiparous ass. with larger babies?
Multip
Maternal infections associated with macrosomia:
UTI (for women undergoing elective c-section)
Puerperal fever (women undergoing trial of labor)
Intrauterine growth may predict the foundations of :
lifelong physiologic function
i.e. IUGR infants more likely ot be overweight later in life
2 primary methods for clinical estimation of fetal weight:
Leopold manuevers
Uterine fundal height
what is the value of ultrasound in mgmt of macrosomia?
It’s ability to rule out the dx
DDx for an enlarged uterus (5)
- large fetus
- multiple gestation
- polyhydranios
- large placenta (molar pregnancy)
- Large uterus (leiomyomata/uterine anomaly/gyn tumor)
at what estimated fetal weight is C-section recommended?
5000g if no diabetes; 4500g if maternal diabetes
