Hearing that you “carry Group B Strep” can sound alarming - but for most women it is completely harmless and very common. Here is what GBS actually is, why it matters around the time of birth, and what your doctor can do about it.
Quick Answer
Group B Strep (GBS) is a common bacterium that many healthy adults carry in the gut or vagina with no symptoms and no harm. It is not a sexually transmitted infection and carrying it does not mean you are unclean or did anything wrong. It matters in pregnancy because, occasionally, GBS can pass to the baby around the time of birth and cause a serious newborn infection. This is uncommon, and it is largely preventable - the main protection is antibiotics given through a drip during labour if you carry GBS or have certain risk factors. Whether and how you are tested varies between hospitals, so ask your doctor what applies to you. After birth, watch your baby for any signs of infection.
What Is Group B Strep?
Group B Streptococcus (GBS, also called Strep B) is a type of bacterium that lives naturally in the body of many healthy people - usually in the gut, and sometimes in the vagina. If you carry it, you are described as being “colonised.”
A few important reassurances:
- It is very common. A significant number of healthy pregnant women carry GBS at some point, often without ever knowing.
- It is not an STI. GBS is not sexually transmitted, and carrying it is nobody’s fault.
- It usually causes no symptoms. Carrying GBS does not make you ill and does not mean you are “unclean.”
- Carriage can come and go. You may carry it at one time and not another.
So if you are told you are GBS positive, it does not mean something is wrong with you.
Why It Matters in Pregnancy
The reason GBS is taken seriously is the newborn baby, not the mother.
Around the time of birth, GBS can occasionally pass from the mother to the baby. In a small number of these babies, it can cause a serious infection such as bloodstream infection (sepsis), pneumonia, or meningitis. This is uncommon - most babies born to GBS carriers are perfectly healthy.
But because it can be serious for a newborn, and because it is largely preventable, your maternity team treats it carefully. The good news is that simple steps greatly reduce the risk.
Prevention - Antibiotics in Labour
The single most effective protection is giving the mother antibiotics through a drip (intravenous) during labour - this is called intrapartum antibiotics. They are offered if you are known to carry GBS or have certain risk factors.
A few things parents often ask:
- Why during labour and not earlier? Treating GBS earlier in pregnancy does not work as prevention, because the bacteria can simply come back before delivery. Giving antibiotics in labour protects the baby at the exact time it matters most - as the baby is being born.
- Who decides the antibiotic? Your doctor chooses whether antibiotics are needed and which one is appropriate, including if you have allergies. (This article does not name any specific medicines or doses - that is your doctor’s call.)
This approach is well established in general obstetric guidance and is the main reason serious newborn GBS infection has become much less common where it is used.
Testing - Screening vs Risk-Based
There are two broad approaches, and practice varies a lot between hospitals and countries:
- Universal screening: Some places test all pregnant women with a simple swab in late pregnancy (commonly around 36-37 weeks) and offer antibiotics in labour to those who test positive.
- Risk-based approach: Other places do not routinely swab everyone. Instead, they give antibiotics in labour if certain risk factors are present.
Risk factors that often prompt treatment include:
- A previous baby who had a GBS infection
- GBS found in your urine during this pregnancy
- Going into labour early (preterm)
- Waters broken for a long time before delivery
- A fever during labour
Because the approach differs from place to place, ask your obstetrician what your hospital does and what applies to you.
Tell Your Maternity Team
Make sure your maternity team clearly knows if:
- You have ever had a baby with a GBS infection, or
- You have tested positive for GBS (in this or a previous pregnancy), especially GBS in your urine
This information directly affects whether you are offered antibiotics in labour, so it is worth mentioning early in your antenatal care and again when you are admitted for delivery.
Watch the Newborn for Signs of Infection
Most newborn GBS infection that appears early shows up in the first hours to days after birth. After your baby is born, seek urgent medical help if your baby shows any signs of being unwell, such as:
- Poor feeding or refusing feeds
- Being unusually sleepy, floppy, or hard to wake - or unusually irritable
- A high temperature (fever) or an unusually low temperature
- Fast, grunting, or laboured breathing
- Simply seeming “not right” to you
Trust your instinct. If your baby does not seem well, do not wait - get them seen urgently.
When to See a Doctor
- During pregnancy: Discuss GBS at your antenatal visits and ask what your hospital’s approach (screening or risk-based) means for you.
- In labour: Report a fever during labour, or if your waters have been broken for a long time - both may change your care.
- After birth: Any sign of newborn infection (above) needs urgent assessment - do not wait at home.
Indian Context
In India, there is no single uniform practice for GBS - some hospitals routinely screen with a late-pregnancy swab, while others follow a risk-based approach. This is completely normal and reflects general obstetric guidance worldwide, which accepts both strategies.
What matters for you is simple: have the conversation. At one of your later antenatal visits, ask your obstetrician:
- Does this hospital screen for GBS, or use a risk-based approach?
- Based on my history, would I be offered antibiotics in labour?
- Is there anything from my previous pregnancies I should flag?
A short antenatal discussion now means there are no surprises when you are in labour.
Frequently Asked Questions
Q: Does carrying GBS mean I have an infection or did something wrong?
A: No. Carrying GBS just means the bacterium lives in your body, usually with no symptoms and no harm. It is extremely common, it is not a sexually transmitted infection, and it is not a sign of poor hygiene or anything you did wrong.
Q: If I’m GBS positive, will my baby definitely get sick?
A: No. Most babies born to mothers who carry GBS are completely healthy. Serious newborn infection is uncommon, and the risk is reduced further by giving antibiotics in labour when needed.
Q: Why can’t I just take antibiotics now to clear it before delivery?
A: Because GBS tends to come back. Treating it weeks before birth does not reliably protect the baby, so antibiotics are given in labour instead - that is when they protect the baby most effectively. Your doctor decides the right timing and medicine.
Q: I tested positive in my last pregnancy. Does that affect this one?
A: It can, so tell your maternity team. A previous GBS-positive result or, more importantly, a previous baby who had a GBS infection are things your doctor will want to know, as they may influence whether you are offered antibiotics in labour.
Q: Will GBS affect how I deliver - normal or C-section?
A: Carrying GBS by itself is usually not a reason for a caesarean. The main step is antibiotics in labour when indicated. Your mode of delivery is decided by your obstetrician based on your overall pregnancy, not on GBS alone.
Worried about a GBS result or what your hospital’s approach means for you? You don’t have to figure it out alone - join here to connect with our team and other expecting parents.
This article is for general information and is not a substitute for personalised medical advice. Always consult your obstetrician.