Intrauterine Growth Restriction

Overview

What is intrauterine growth restriction?

Intrauterine growth restriction (IUGR) is a term that describes a baby who is not growing at the normal rate inside the uterus. These babies usually have a low weight at birth.

Symptoms

Do all small babies have IUGR?

No. About one-third of the babies who are small at birth have IUGR. The rest of them don’t have IUGR–they’re just smaller than normal. Just like there are different sizes of infants, children and adults, there are also different sizes of babies in the uterus. Small babies tend to run in families. The parents or other children in the family may have been small when they were born, too.

What health problems does IUGR cause?

Babies who have IUGR are more likely to have certain health problems (both during pregnancy and after birth). Problems include:

  • A difficult time handling the stress of vaginal delivery
  • Increased risk of being stillborn
  • Low blood sugar level at birth
  • Lower resistance to infection
  • Trouble maintaining body temperature
  • An abnormally high red blood cell count

Will my baby grow up to be normal in height?

Your baby will probably catch up in size and have a normal height by about 2 years of age.

Causes & Risk Factors

What causes IUGR?

IUGR has various causes. The most common cause is a problem in the placenta (the tissue that carries oxygen, food and blood to the baby). Birth defects and genetic disorders can also cause IUGR. If the mother has an infection, high blood pressure, kidney disease, heart disease or sickle cell anemia, or is smoking, drinking alcohol or abusing drugs, her baby might develop IUGR. Sometimes a prescribed medicine that the mother is taking causes IUGR.

Did I cause this problem?

Most of the causes of IUGR are beyond your control. Usually, nothing the mother did causes IUGR in her baby. But if you smoke cigarettes, drink alcohol or abuse drugs, you can cause IUGR in your baby.

If I have another baby, will that baby also have IUGR?

Generally, no. IUGR usually doesn’t occur in another pregnancy. But in some women, it does happen again. Women who have another pregnancy affected by IUGR usually have an illness, such as hypertension, that causes IUGR. Good control of illnesses before and during pregnancy lowers the risk of having another baby with IUGR.

Diagnosis & Tests

How will I know if my baby is just small or has IUGR?

During your pregnancy, your doctor will do tests to find out if your baby is growing normally. The main test for checking a baby’s growth in the uterus is an ultrasound. The ultrasound exam lets your doctor see your baby in your uterus with an instrument that is moved across your abdomen.

While you are having an ultrasound exam, your doctor will measure the size of your baby’s head, abdomen and legs. These measurements will tell you and your doctor if your baby is growing normally. Your doctor will also find out the amount of amniotic fluid in your uterus. In some babies who have IUGR, the amount of amniotic fluid is low. If your baby is small, ultrasound exams may be done more often than usual to check your baby’s health.

Are there other tests I might have?

One test is fetal monitoring. It’s a way to check your baby’s health inside your uterus. Straps are put over your uterus as you lie down for about 30 minutes. You will hear your baby’s heartbeat as it is recorded. Your doctor can look at the recording and see if your baby’s heartbeat is normal.

You might also have an amniocentesis. A needle is put through your skin into your uterus. A few teaspoons of amniotic fluid are withdrawn in the needle. The fluid is tested to see if it shows the cause of the IUGR. The amniotic fluid can detect infection and some chromosomal abnormalities that can cause genetic problems.

Treatment

What can I do to help my baby while I’m pregnant?

The best way to help your baby is to keep all of your prenatal visits with your doctor. You should also monitor how often your baby moves and kicks. A baby who moves around often is usually healthy. A baby who doesn’t move very often or who stops moving may be sick. If you notice your baby isn’t moving as much, call your doctor.

Another way you can help your baby is to take good care of your body. Eat plenty of healthy foods and take in the recommended amount of calories for a pregnant woman. Rest will help you feel better and it may even help your baby grow. Try to get 8 hours of sleep (or more) each night. An hour or 2 of rest in the afternoon is also good for you. Finally, if you smoke, drink alcohol or use drugs, stop now. These things can hurt your baby. This may be all that is needed to improve your baby’s health, as well as your own.

If my baby has IUGR, will I have to give birth early?

Maybe not. The time of delivery depends on how well your baby is doing. Sometimes, babies with IUGR keep on growing in the uterus. If your baby keeps gaining some weight, an early delivery may not be needed. But if your baby is not growing at all or has other problems, your doctor may decide that an early delivery could help. In this case, your doctor may want to induce labor. Your baby’s heart rate and movements will be closely watched to help you and your doctor make this decision.

Will I need to have a cesarean section?

If there are no signs of problems with your baby during labor, a vaginal delivery is okay. Some babies with IUGR are weak. The stress of labor and delivery may be too much for a weak baby. If your baby has problems during labor, a cesarean section (also called a C-section) may be safer.

Will my baby need to stay in the hospital longer than usual?

Probably, especially if your baby was born early. Babies who are small at birth need to stay in the hospital until they can breathe and feed normally. After your baby is born, the doctor will check your baby’s weight to make sure the baby is growing. Generally, babies stay in the hospital until they weigh about 5 pounds and can breathe and feed normally.

Other Organizations

Questions to Ask Your Doctor

  • How often do I need an ultrasound?
  • Is my baby underweight?
  • Does he/she have intrauterine growth restriction (IUGR)?
  • What is the likely cause of IUGR?
  • Do I/Does my baby need treatment? What treatment do you recommend?
  • Will I need to deliver early? Will I need a C-section?
  • What lifestyle changes can I make at home to make sure my baby is healthy?
  • After my baby is born, what health problems is he/she likely to have?
  • Will my baby need special care? Will he/she need to stay in the hospital?

Citations

  • Intrauterine Growth Restriction: Identification and Management by David Peleg, M.D., Collen M. Kennedy, M.D., and Stephen K. Hunter, M.D., PH.D.( 08/01/98, http://www.aafp.org/afp/980800ap/peleg.html)