Intrauterine Growth Restriction – IUGR Awareness
March 13, 2019 @ 8:00 am - 5:00 pm EDT
What is IUGR?
IUGR is a condition which affects the growth of babies in the womb with the baby’s growth velocity slowing down or in some cases ceasing during pregnancy leading to a low birth weight. There are several definitions, but generally it is thought that babies affected by IUGR will weigh in the lowest 10% for babies at the same gestational age. Some babies in this group are just constitutionally small and are not specifically growth restricted.
Concern of IUGR arises when a baby’s growth, which may have started normally, then slows and falls below the expected pattern which implies an underlying problem causing the restriction in growth.
What causes IUGR?
It is not always known what causes IUGR. Potential causes include:
- Problems with the placenta which supplies the baby with oxygen and nutrients essential for growth and development. Problems can include the placenta being too small or a placenta which is starting to detach from the uterus, otherwise known as placental abruption;
- Medical conditions in the mother, for example chronic hypertension (high blood pressure), pre-eclampsia, heart disease;
- Chromosomal abnormalities.
Potential risk factors for IUGR should be considered in early pregnancy.
Potential complications of IUGR
Babies affected by IUGR can suffer complications during pregnancy, birth and in later life, including:
- Intrauterine death (stillbirth) or death in the neonatal period;
- Oxygen deprivation and distress during labour leading to brain injury and cerebral palsy;
- Hypoglycaemia (low blood sugar) and/or jaundice in the newborn period. Both conditions if not properly treated can cause brain damage.
IUGR is very serious and therefore it is vital that the problem is picked up during pregnancy where possible and appropriate action taken to limit the risk of these serious complications occurring.
How is IUGR diagnosed?
Methods of diagnosing IUGR during pregnancy include:
- Regular measuring of the symphysis fundal height (the pregnancy bump). Concern arises if the growth is plotted below the 10th centile or the growth crosses into a lower centile than where it had been at a previous measurement and further investigations should be considered.
- Serial ultrasound growth scans, measuring the baby’s abdominal circumference, head circumference and estimated weight.
Further investigations by Doppler scans, to check blood flow to and from the baby, and to monitor the baby’s wellbeing, may also then be undertaken to guide doctors as to when delivery may be required.
Delivering a baby with IUGR
When and how to deliver a baby affected by IUGR will depend on a number of factors including how severely growth restricted the baby is and the results of ongoing monitoring and investigations. If there are serious concerns then the baby should be delivered before term by caesarean section.
If there is less concern then vaginal delivery can be trialled with continuous monitoring by CTG and if there are signs of distress then the baby should be delivery more urgently by caesarean section instead. A baby affected by IUGR is generally less able to cope with the demands of labour and therefore the baby’s wellbeing needs to be carefully monitored.