Small baby

Small babies are usually healthy, but if they're small because they aren't growing properly, they need extra attention

If you’ve been told that your baby is small or small for gestational age (SGA), it’s because your baby’s weight is estimated to be in the lowest tenth centile. This means that if you had a group of 100 babies at the same stage of pregnancy, your baby would be one of the ten smallest ones

Most small babies are healthy during pregnancy and when they’re born. But some babies are small because they aren’t getting a healthy supply of nutrients and oxygen through the placenta. Or they may have an infection or genetic disorder affecting their growth. These babies are said to be growth restricted. They need to be identified so they can be monitored. A baby who is growth restricted may need an early delivery to reduce the risk of serious problems or stillbirth

Measuring your baby’s growth is one of the reasons why it’s so important to go to all your antenatal appointments. Your midwife estimates your baby’s growth by measuring your bump and recording it on your baby’s growth chart, which is in your maternity notes. By checking the pattern of growth over time, your midwife can check that your baby is continuing to grow healthily

Possible causes of growth restriction

  • Placenta doesn’t work as well as it should – high blood pressure and pre-eclampsia, smoking, and using street or recreational drugs can affect how well the placenta works
  • Infection
  • Developmental and genetic problems

There are some ways of reducing the risk of growth restriction

Go to all your antenatal appointments, too, so your baby's growth can be checked

More information

The Royal College of Obstetricians and Gynaecologists has information on having a small baby