Baby bumps come in all different shapes and sizes. So while it can be difficult, try not to compare your baby bump to anyone else’s. No two women or two pregnancies are the same. Your baby’s health is the main priority and your midwife will measure your baby’s growth as part of your antenatal care to check that everything is OK.
You can talk to your midwife at any time if you are concerned about how your baby is growing.
How is a baby's growth measured in pregnancy?
Your midwife will ask you to lie down and will measure from the top of your bump to the top of your pubic bone using a tape measure. These measurements should be taken at each antenatal visit from around 24 weeks.
The measurement should be within 2cm of the number of weeks you are pregnant. For example, when you're 30 weeks pregnant, your measurement should be somewhere between 28cm and 32cm. This will depend on:
- your height and weight in early pregnancy
- how many children you’ve had
- your ethnicity.
How can the midwife or doctor tell if the baby is not growing?
Your baby’s growth is written in your antenatal notes either as a measurement (written down as fundal height’ (FH) or symphysis-fundal height (SFH)) or plotted on a chart through your pregnancy. This chart can show the midwives if there is a steady incline, no growth or decline in the growth.
Many hospitals are now using personalised growth charts and marking your measurements on these. This makes checks on the baby’s growth more accurate.
You can always ask your midwife if you’d like to know how your baby’s growth is being monitored.
When should I talk to a doctor about my bump not getting bigger in pregnancy?
Call your midwife if you are concerned that your bump isn’t getting bigger and ask for an extra antenatal appointment to be measured.
Call your midwife or maternity unit at the hospital immediately if you feel your bump isn’t getting any bigger AND your baby’s movements have slowed down. Your baby moving normally is a sign that they are well. You should be offered a scan and extra monitoring.
If your measurements are outside of the normal range, or if you still feel worried that your bump is too small, your midwife should recommend an ultrasound scan called a growth scan.
This will show the baby’s growth more clearly. If the scan shows the baby is growing normally, this is more accurate than the measurements.
If the scan shows that your baby isn’t getting bigger you will be referred to a consultant. This means you will have all your antenatal appointments at the hospital and you will see a midwife and a consultant. If they are concerned about your baby’s growth you may have more growth scans.
Intrauterine growth restriction (IUGR), also known as fetal growth restriction (FGR)
Intrauterine growth restriction is a condition where the baby’s growth slows or stops during pregnancy. It is often caused by problems with the placenta that restrict oxygen and blood going to your baby. 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. Find out more about intrauterine growth restriction
Being aware of your baby's movements is important
If your midwife or doctor has told you that your baby may not be growing as they should, it is very important to monitor your baby's pattern of movements because they are a sign that your baby is well. If your baby is not getting enough oxygen they may move less to conserve their energy. If you notice a change, report it to your midwife or doctor immediately. Read more about movements here.