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Intrauterine Growth Restriction

Intrauterine growth restriction (IUGR) is a condition in which a baby is smaller than expected for its gestational age.

We estimate size by combining measurements of the head, abdomen, and thigh bone on ultrasound. When the measurements show that the baby is among the smallest ten percent of all fetuses (the tenth percentile), he or she is considered likely to have IUGR.

Causes of IUGR

  • Maternal infection
  • Reduced blood flow to the placenta
  • Birth defects such as chromosome problems or rare genetic syndromes
  • Medical complications such as diabetes, chronic hypertension, preeclampsia, or malnutrition
  • Smoking
  • Drug abuse
  • Sometimes no cause is found. It could be due to the fact that both parents are smaller than average.

Managing IUGR

IUGR may be a sign that the baby is having problems, so we may recommend extra testing during pregnancy. If IUGR occurs very early on, is exceptionally severe, or there are other risk factors, we may suggest genetic testing. Repeated ultrasounds every two to three weeks may be a good idea to see if the fetus is continuing to grow. Twice-weekly non-stress tests, which may be done during the third trimester, monitor the baby's heartbeat.

Sometimes, delivery is the best idea:

  • If the pregnancy has reached the due date
  • If absolutely no growth is detectable by ultrasound after several weeks
  • If there are signs that the fetus is in immediate danger

Birth and beyond

Labor may be hard on a baby with IUGR, so we will monitor the baby very closely during labor.

IUGR babies may have little fat and low muscle tissue development. This may make it difficult for them to maintain their temperature and blood sugar. Sometimes they will need extra care.

If the baby is delivered early, he or she may have complications from being premature.

Most IUGR babies grow rapidly after birth and catch up to their normal-sized counterparts.

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