Intrauterine Growth Restriction - Definition and Overview

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 praevia
• Cord anomalies