Pregnancy Second/third trimester Also: HC

Head circumference

Abbreviation: HC

Head circumference (HC) is an ultrasound measurement of the distance around the outer edge of your baby's skull. It gives doctors a picture of overall brain and skull growth and is one of several measurements used to calculate estimated fetal weight and assess development. HC is plotted on a percentile chart, and results are most meaningful when tracked across multiple scans over time. Measurements that are significantly small may prompt further assessment for conditions affecting brain development, while larger measurements may be a normal family trait or may warrant a follow-up scan. Always discuss results in context with your obstetrician rather than interpreting them in isolation.

What This Means for You

Understanding Head circumference is an important part of your second/third trimester journey. During pregnancy, your care team will use this term regularly. Being familiar with it means you can ask better questions and feel more confident at your antenatal appointments.

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Good to Know

After birth, your baby's head circumference will be measured at every child health check at the polyclinic, forming part of the growth monitoring record that continues through early childhood in Singapore.

Related Terms

Source: https://www.acog.org/womens-health/faqs/how-your-fetus-grows-during-pregnancy

Always consult your healthcare provider for personalised advice.

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Medical Disclaimer: This glossary is for informational purposes only and does not constitute medical advice. Always consult a qualified healthcare professional for diagnosis and treatment.

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