My bump is too small

A growing bump is the sign of a growing baby. Your midwife should start measuring your baby from 24 weeks to make sure they are growing well.

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 2 women or 2 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 (pregnancy) care to check that everything is OK. 

Speak with your midwife at any time if you are concerned about how your baby is growing.  

How is my 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 and plotted on a growth chart at each antenatal visit from around 24 weeks

The measurement should be similar to the number of weeks pregnant you are - for example when you're 30 weeks pregnant, your measurement should be somewhere between 28cm and 32cm.  

However, your measurements can depend on: 

  • your height and weight in early pregnancy 
  • how many children you’ve had 
  • your ethnicity. 

Many hospitals are now using personalised growth charts, which take more of your personal characteristics into account, and marking your measurements on these. This makes checks on the baby’s growth more accurate.  

How do I know if my baby is not growing properly in pregnancy? 

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 steady growth, no growth or decline in the growth. 

You can always ask your midwife if you’d like to know how your baby’s growth is being monitored. 

What are the symptoms of a baby not growing properly? 

There are no symptoms of a baby not growing well. Your healthcare professional should be able to tell if there are any issues by measuring your bump during your antenatal appointments. This will show the midwives if there is steady growth, no growth or decline in the growth. 

But you can call your midwife at any time if you are concerned that your bump isn’t getting bigger. You can 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, stopped or changed. If your baby isn’t moving they may be unwell. You should be offered a scan and extra monitoring. 

If your bump/stomach gets bigger suddenly in pregnancy 

Call your midwife if you are concerned that your stomach gets bigger suddenly. This may be a sign of polyhydramnios. This is where there is too much amniotic fluid around the baby during pregnancy. Amniotic fluid is the fluid that surrounds your baby in the womb. 

Sometimes you may need treatment to reduce the amount of fluid.

Growth scan 

If your measurements are outside of the normal range, or if you still feel worried that your bump is too small, your midwife should offer an ultrasound scan called a growth scan. 

This will show the baby’s growth more clearly and is more accurate than using a tape measure alone.   

If the scan shows that your baby isn’t growing as expected 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 doctor (consultant). If they are concerned about your baby’s growth you may have more growth scans. 

Fetal growth restriction (FGR) (sometimes known as Intrauterine growth restriction (IUGR)  

Up to 1 in 10 (10%) of pregnancies will be affected by fetal growth restriction, which is when the baby is small and lighter than they should be for that stage of pregnancy. 

FGR can happen when the placenta is not working well enough to provide the baby with the nutrients they need to grow normally. But we don’t always know why FGR happens.  

If your healthcare professional thinks your baby has fetal growth restriction you may need more check-ups during your pregnancy. In some cases, you may need to give birth earlier than expected if the baby is in danger.  

If you have had FGR in a previous pregnancy you should be offered additional growth scans in your current pregnancy so that your baby's growth can be monitored. 

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 movements because they are a sign that your baby is well. If your baby is not getting enough oxygen or nutrients, they may move less to save energy. Contact your midwife or maternity unit immediately If you notice your baby’s movements have slowed down, stopped or changed.   

Find out more about your baby’s movements

Perinatal Institute 

NHS. Polyhydramnios (too much amniotic fluid) (Page last reviewed: 4 May 2020 Next review due: 4 May 2023) 

NHS Inform. Fetal Growth Restriction Last updated, 22 September 2020

Nardozza, L.M.M., Caetano, A.C.R., Zamarian, A.C.P. et al. Fetal growth restriction: current knowledge. Arch Gynecology and Obstetrics 295, 1061–1077 (2017).

Review dates
Reviewed: 21 February 2023
Next review: 21 February 2026