Group B Strep (GBS): why does the US test for it and India/UK usually don't?
In short
- GBS (Group B Strep) is a common germ. Carrying it usually causes you no symptoms.
- It can rarely affect a newborn during birth.
- The US tests everyone with a swab at 36 to 38 weeks. The UK does not test everyone.
- India has no single national rule — ask your own doctor what they do.
What happens
- In the US approach: a swab sample is taken from the vagina and rectum, usually between 36 and 38 weeks.
- If you test positive, you're usually offered antibiotics through a drip once labour starts.
- In the UK and (where practised) India, your doctor may instead watch for specific risk factors during labour rather than testing everyone in advance.
The details: numbers and where they differ
The numbers
| Measure | Value | Source |
|---|---|---|
| GBS culture screening window (where performed) (pregnant women, US (ACOG)) | 36–38 weeks gestation | American College of Obstetricians and Gynecologists (ACOG) |
Where sources disagree
Whether GBS screening is routine
Sources differ here — shown side by side, not blended into one number.
United States (ACOG)
Recommends routine vaginal-rectal culture screening for every pregnant woman, at 36 to 38 weeks, with antibiotics offered during labour if the result is positive.
United Kingdom (NICE, via a charity summary)
Does not recommend routine antenatal testing for GBS, citing a lack of randomised evidence, the low predictive power of testing, concerns about unnecessary antibiotic use, and broadly similar rates of newborn GBS infection in countries that do and don't screen.
India
No national MoHFW or FOGSI policy on routine GBS screening was found for this page. This is stated as an acknowledged gap in available guidance, not a position — ask your own doctor what they recommend.
When to call your doctor
- If you want to know your own doctor's or hospital's policy on GBS testing, ask them directly — practice genuinely varies.
- If you develop a fever during labour, or your waters break well before labour starts — mention this promptly, as these are among the risk factors doctors watch for.
Discuss your results with your doctor: this page reports what these sources say, not advice for your situation.
Sources
- American College of Obstetricians and Gynecologists (ACOG), Group B Strep and Pregnancy (Patient FAQ). Named as the guideline this section describes; its text and tables are not reproduced here (All rights reserved (cite only)). Recommends a vaginal-rectal swab culture for every pregnant woman between 36 and 38 weeks as part of routine prenatal care in the US.
- Group B Strep Support (charity summary of UK NICE guidance), Key points for health professionals. Named as the guideline this section describes; its text and tables are not reproduced here (Charity-hosted summary, not the primary NICE guideline text (cite only)). Summarises the UK position as not currently recommending routine antenatal GBS testing, for the reasons stated above. This is a secondary summary, not the primary NICE guideline document; re-check against NICE directly before relying on it clinically.
Sources checked 2026-09-26. How we source and check every page.
Educational summary of named sources, not medical advice.