Fetal anatomy scan

Some pregnant women will be offered a fetal anatomy scan at 18 to 22 weeks. These are also called 'anomaly scans'. Some hospitals offer this to every pregnant woman. Other hospitals can only offer this to women with higher risk pregnancies.

Fetal anatomy scans can tell you:

  • how your baby is developing in the womb
  • birth defects like spina bifida and heart problems
  • the sex of your baby (remember, scans can sometimes get this wrong)

Most scans will show you that your baby is developing normally.

Sometimes a baby is born with a health problem. A fetal anatomy scan will detect many of these problems. This allows you and your obstetrician to make plans for the birth and for any aftercare you and your baby may need.

The scan will not detect all health problems. No test is 100% accurate. Some health problems do not show up on the fetal anatomy scan. These include some cases of Down syndrome, some cases of cerebral palsy and autism.

If the scan shows that your baby is growing too quickly or too slowly, extra scans may be offered to check your baby's growth.

Baby's gender

Sometimes the radiographer or midwife doing the scan may not be able to see parts of your baby's body. For example, they may not be able to see the genitals to determine the baby's gender.

If you do not wish to know the gender of your baby during the scan, tell the person doing the scan. Bear in mind that it is not always possible to tell the baby's gender from the scan.

Bring someone with you

An ultrasound scan can be a happy event. But sometimes they can detect that your baby is unwell. Or you might get unexpected news - like you're expecting more than one baby.

Having someone with you will be a good support at this time.

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This project has received funding from the Government of Ireland’s Sláintecare Integration Fund 2019 under Grant Agreement Number 8.

Page last reviewed: 15 March 2018
Next review due: 15 March 2021