Intrauterine Growth Restriction (IUGR) refers to the condition in which a foetus is unable to grow to its genetically determined potential size to a degree that may affect the health of the foetus. This can be contrasted to small for gestational age (SGA). Not all foetuses that are SGA have IUGR.

Possible maternal causes of IUGR (adapted from Severi, 2000) include the following:

Chronic hypertension Pregnancy-associated hypertension Cyanotic heart disease Class F or higher diabetes Hemoglobinopathies Autoimmune disease Protein-calorie malnutrition Smoking Substance abuse Uterine malformations Thrombophilia

Possible causes of IUGR related to the placenta and/or umbilical cord include the following:

Multiple gestation Twin-to-twin transfusion Abnormal cord insertion Placental abnormality Chronic abruption Placenta previa Cord anomalies