Fetal growth restriction Flashcards
What are the risk factors for fetal growth restriction
Pre-pregnancy conditions
Present pregnancy conditions
Prior maternity and family history
Maternal teratogenic exposure
Maternal exposure to infection (especially in 1st trimester)
What are some maternal pre-pregnancy condition that causes risk of FGR
Hypertensive disorders
Diabetes
Renal disease
Collagen vascular disease
Autoimmune disorders
Thombophilias
Some hemoglobinopathies
Severe anemia
Pre-pregnancy BMI <20 or >30
Use of assisted reproductive technologies
What are some present pregnancy conditions that cause risk of FGR
Multiple gestation
Hypertensive disorders
Inadequate weight gain particularly if associated with low protein intake
Placental abnormalities
Circumvallate placenta,
placenta accreta,
single umbilical artery partial placental infarction,
hemangioma,
placental abruption, and
placenta previa)
Relative hypoglycemia or a flat response on a 3-hour glucose tolerance test, reflecting reduced glucose supply to the placenta
Unexplained abnormal serum genetic screening
What are some prior maternity and family history conditions that cause risk of FGR
Prior history of FGR infant
Family or personal history of infant with chromosomal abnormalities, congenital malformations or genetic syndrome
What are some maternal teratogenic exposures conditions that cause risk of FGR
Smoking
Moderate alcohol use
Substance use
Environmental exposures
What are some maternal exposure to infection (especially during the first trimester) conditions that cause risk of FGR
CMV
Rubella
Toxoplasmosis
Herpes Simplex
Syphillis
How might fetal growth restriction present?
Objective:
A fundal height measurement of 3 cm less than dates in women with certain pregnancy dating.
Experienced clinicians sometimes detect weight smaller than expected for gestational age through palpation.
Diagnosis of FGR is made by consecutive ultrasound measurements performed at least 3 weeks apart.
Subjective:
What are the differential diagnoses for those subjective and objective findings
Incorrect dates
Oligohydramnios
SGA
Constitutionally SGA
FGR
Fetal position
Maternal habitus
Types of fetal growth restriction
Symmetric
Asymmetric
Symmetric fetal growth is caused by:
Maternal drug use
Asymmetric fetal growth is caused by
Abnormalities in uteroplacental perfusion
How is fetal growth restriction diagnosed
U/S
Symmetric FGR/IUGR
Definition: Both the fetal head and fetal abdominal measurements are smaller than the 10th percentile.
Etiology: Occurs as the result an insult early in gestation (such as a severe infection or a chromosomal anomaly) which leads to a decrease in the overall number of cells in the fetus’s body.
Outcomes: Associated with increased in morbidity and mortality.
Occurs earlier in gestation and is longer-standing
Asymmetric FGR/IUGR
Definition: Fetal head circumference is relatively normal while the abdominal measurements are smaller than the 10th percentile.
Asymmetric IUGR is often referred to as “brain sparing” because the head size remains normal while the body size (as represented by the abdominal measurement) is decreased.
Etiology: Occurs as a result of later pregnancy insults such as hypertension.
Asymmetric FGR is more common than symmetric.
Has a higher probality of no long-term sequelae b/c its brain-sparing, occurs later in gestation
What are the diagnostic criteria for fetal growth restriction?
Additional ultrasounds for fetal evaluation will likely take place, including for amniotic fluid evaluation and doppler blood flow studies in the case of FGR.
