Pregnancy Third trimester

GBS swab

The GBS swab is a simple, quick test done late in pregnancy, usually between 35 and 37 weeks, to check whether Group B Streptococcus bacteria are present. A swab is gently taken from around the vagina and rectum and sent to a lab for culture. Results are usually available within a few days. The swab is not painful and takes only a moment. A positive result means antibiotics will be recommended through a drip during active labor to protect your baby from infection at birth. Even if you tested negative in a previous pregnancy, you should be retested each time, as your GBS status can change.

What This Means for You

Understanding GBS swab is an important part of your 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

At KKH and NUH, the GBS swab is typically offered as part of routine third-trimester care, though some women with specific risk factors such as preterm labor or fever in labor may receive preventive antibiotics regardless of their swab result. Keep a copy of your result in your hospital bag as a reminder for the labor ward team.

Related Terms

Source: https://www.acog.org/womens-health/dictionary

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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