IUGR: etiology

UTEROPLACENTAL INSUFFICIENCY (80%)

maternal causes
- deficient supply of nutrients: smoking, malnutrition, multiple gestations, anemia, high altitude
- maternal vascular disease (more common): severe diabetes,
primary placental causes
- extensive placental infarctions, chronic partial separation, placenta previa

PRIMARY FETAL CAUSES (20%)

decreased intrinsic growth; symmetrical IUGR
congenital heart disease, genitourinary anomalies, CNS anomalies, chromsomal abnormalities (trisomy 13, 18, 21), viral infection (rubella, CMV)