Children's Hospital Colorado
Colorado Fetal Care Center

Fetal Growth Restriction (Intrauterine Growth Restriction)

We see more, treat more and heal more kids than any other hospital in the region.

U.S. News & World Report ranked in all 10 specialties badge

Get Care

Would you like to learn more about us?
checked box icon Colorado Fetal Care Center
Do you have questions about this condition?
Want a second opinion?
Two checked boxes icon Get started

What is fetal growth restriction?

Fetal growth restriction (FGR) is a condition in which unborn babies are smaller and/or develop at a slower rate than is typical. FGR is also known as intrauterine growth restriction (IUGR).

If your baby’s development puts them in the 10th percentile or lower (meaning they are smaller than 90% of babies at the same point in pregnancy), they may have fetal growth restriction.

What causes fetal growth restriction?

Fetal growth restriction can occur during any stage of pregnancy. A placenta that doesn’t function properly to nourish the developing baby is the most frequent cause of FGR.

Poor placenta function (also called placental insufficiency) is more common in twin or other multiple pregnancies. It can lead to one or more babies with FGR during pregnancy and a low birthweight.

Maternal habits and conditions can also increase the risk of fetal growth restriction. These can include:

  • Alcohol or drug use
  • Anemia
  • Autoimmune diseases
  • Kidney disease
  • Liver disease
  • Diabetes
  • High blood pressure
  • Poor nutrition
  • Smoking

Problems with the baby that can lead to FGR include:

  • Infection
  • Fetal anatomy abnormalities
  • Being one of multiple fetuses (twins, triplets or more)
  • Being born at high altitude
  • Chromosomal abnormalities

Who gets fetal growth restriction?

Fetal growth restriction can affect babies of either sex. It’s very common in multiple pregnancies (twins, triplets or more). As mothers age, there is greater risk for chronic medical conditions (such as high blood pressure and diabetes). Mothers with those conditions may be more likely to experience fetal growth restriction during pregnancy.

Next steps