Intrauterine growth restriction (IUGR) occurs in around 3 in every 100 pregnancies. Unborn babies with IUGR can grow so slowly in the womb that they are at risk of health problems. If the growth restriction is severe, the baby may have to be delivered, so it is also a cause of premature birth.
Causes of Intrauterine Growth Restriction
The majority of cases of IUGR are caused by failure of the placenta but there are also several other factors that could cause a baby's growth to be restricted:
- multiple pregnancy
- Antiphospholid Syndrome
- genetic problems or a congenital anomaly in the baby
- pre-existing medical problems in the mother such as high blood pressure, kidney disease, diabetes, heart disease, lung disease, chronic anaemia
- certain prescribed medications such as warfarin, some but not all anticonvulsants, and some anticancer drugs
- low pregnancy weight
- smoking or using drugs during pregnancy
- drinking alcohol during pregnancy.
Around 10 in every 100 babies are small for gestational age. Most of these are small for normal reasons, such as the mother’s size and ethnicity, but around a third will be due to intrauterine growth restriction.
Signs and symptoms of Intrauterine Growth Restriction
IUGR is normally diagnosed during routine antenatal appointments. Your baby’s size is monitored throughout your pregnancy in your routine appointments. The midwife will palpate your stomach gently to feel the baby’s size, and they will measure the fundal height. The measure is then put on a chart that plots the growth. If there are any concerns the midwife will refer you for a scan. This does not necessarily mean something is wrong, but it is important to have the scan as more accurate way of assessing the baby's growth.
Management of Intrauterine Growth Restriction
There is no 'treatment' for IUGR. Instead you will have a management plan. If IUGR is suspected, you will have regular scans to look at the baby’s growth. The blood flow through the placenta will be checked with a uterine artery doppler test. If there is concern about growth then a plan will be implemented including regular scans, CTG monitoring and consultant appointments in antenatal clinic at the unit.
If the growth restriction is severe, your healthcare team will recommend additional scans for monitoring of growth and baby well-being. They may recommend delivering the baby early.
It is very important to be aware of your baby’s pattern of movements and monitor this for change if you have been diagnosed with suspected IUGR.
A growing bump is the sign of a growing baby. Your midwife should start measuring your growing baby at antenatal appointments from 24 weeks to make sure they are growing at the right rate for your stage of pregnancy.
Intrauterine infection is infection within the womb.
Diabetes is a condition in which there is an inability to control blood sugar levels and it leads to high amounts of sugar in the blood. Gestational diabetes is diabetes that develops during pregnancy.
Frequently asked questions on the causes of premature birth
The way your life is lived can have an effect on your risk of premature birth.
- NICE (2008) Antenatal care: routine care for the healthy pregnant woman. National Institute for Health and Clinical Excellence.
- NICE (2011) CG129 Multiple pregnancy: The management of twin and triplet pregnancies in the antenatal period, National Institute for Health and Clinical Excellence.
- Norman J (2011) Preterm labour, managing risk in clinical practice. Cambridge: Cambridge University Press.
- RCOG (2013) The Investigation and Management of the Small–for–Gestational–Age Fetus. The Royal College of Obstetricians and Gynaecologists.
- James D, Steer P (2011) High risk pregnancy, management options. Fourth ed, Elsevier Saunders.
ℹLast reviewed on October 3rd, 2016. Next review date October 3rd, 2019.
By Midwife @Tommys on 22 Sep 2016 - 10:21
We are very sorry to hear about William and hope our information can give you some understanding of what happened. Thank you for your feedback. Best wishes from all at Tommy's.
By Anonymous (not verified) on 21 Sep 2016 - 17:06
I found this page informative and easy to follow. I wish I had known about it when I was diagnosed with placenta problems which
led to William being growth restricted and eventually stillborn. I feel it was never fully explained to me at the time and I was told all it meant was I needed more monitoring and that I would not be going to term.