Group B streptococcus in newborn babies Streptococcus Rōpū B ki ngā piripoho

If you have GBS in your body, it is called GBS carriage or colonisation. It is not considered to be an infection.

Some women have GBS and others do not. The reason is not known. It is not a sign of ill health or poor hygiene.

You do not need antibiotics if you have GBS carriage during pregnancy, but you may be treated with antibiotics during labour. You will need antibiotics if you have an infection in your wee (urine) caused by GBS.

If you have GBS while you are pregnant, you can pass it to your pēpi in 2 ways.

• The bacteria can move up your vagina and get into the fluid surrounding your pēpi after your waters break.
• Your pēpi can pick it up while passing through your vagina at birth.

Most pēpi are not affected but a very small number become infected.

Early-onset GBS infection happens if your pēpi develops GBS infection within 7 days of birth.

• 70% of affected pēpi have symptoms at birth.
• 95% of affected pēpi have symptoms by 24 hours after birth.

In Aotearoa New Zealand, about 30 pēpi every year get early-onset GBS infection.

While GBS infection in pēpi is rare, it is the most common cause of life-threatening infection in pēpi during the first week of life.

Signs of GBS infection in pēpi include:

• being floppy, or stiff and unresponsive
• poor feeding or throwing up (vomiting)
• difficulty breathing, or grunting
• high or low body temperature
• fast or slow heart rate
• pale or blotchy skin
• irritability
• shrill or moaning cry, or whimpering.

Late-onset GBS infection develops 7 or more days after pēpi is born. These pēpi pick up the bacteria at birth but probably become infected after birth.

GBS infection after 3 months is extremely rare.

You are more at risk of passing GBS to your pēpi if:

• you have already had a pēpi affected by GBS infection
• you have had a GBS urine infection in this pregnancy
• you have a high temperature (38°C or higher) during labour or when your waters break
• you go into labour at earlier than 37 weeks
• your waters break more than 24 hours before you go into labour (this is called prolonged rupture of membranes)
• you are diagnosed as carrying GBS in your vagina or bottom (rectum) at 37 weeks in this pregnancy.

If you have any risk factors for passing on GBS, you will be offered antibiotics during your labour. These are intravenous antibiotics (given into a vein), also called IV antibiotics. They will reduce the chances of your pēpi getting the infection. 

Your midwife or doctor will also monitor the health of your pēpi for at least 24 hours after birth.

If your pēpi is at risk for GBS infection but you choose not to have IV antibiotics during labour or for at least 4 hours before the birth, your pēpi will need to be watched more closely. This includes 4-hourly checks for the first 24 hours.

If you are worried about your pēpi, talk to the hospital staff, or contact your midwife or doctor if you are at home.

Complications for your pēpi

GBS in a pēpi can cause an infection in their:

• lungs (pneumonia)
• blood (septicaemia)
• brain (meningitis).

It can make pēpi seriously ill, and some die from it.

Most pēpi make a full recovery after having treatment with antibiotics and receiving intensive care. But even with the best medical care, 5% to 10% of pēpi with early-onset GBS infection die. Most of the pēpi who die from GBS infection are born early (before 37 weeks).

A few infected pēpi are affected permanently with problems such as:

• cerebral palsy
• deafness
• blindness
• serious learning difficulties.

Complications for the mother

Rarely, GBS can cause an infection in the mother, such as an infection in the uterus or urinary tract.

A more serious infection that can happen is infection of the blood (septicaemia). This may cause symptoms throughout your body such as:

• fever
• rapid heart rate
• generally feeling unwell.

If it is not treated early, your body can react to this infection causing you to become very unwell. This is called sepsis. Sepsis can stop organs such as your kidneys from working properly, which can be life threatening.

Most GBS infection in newborn pēpi can be prevented by:

• identifying mothers whose pēpi are at higher risk
• treating the mother with antibiotics during labour.

Antibiotics given in labour do not prevent late-onset infection.

You may find you have GBS when other tests are done, such as:

• a swab from your vagina
• a mid-stream urine sample (MSU).

GBS can come and go. It is hard to know if it will be in your vagina when you give birth, which is how it can infect your pēpi.

Swabs taken more than 5 weeks before labour are not good at predicting whether GBS will be there when you are in labour.

If you have GBS any time before 37 weeks of pregnancy, it is best to have a repeat swab from your vagina and rectum at 37 weeks. You can take the swab yourself or your midwife or a doctor can do it.

Your midwife or doctor will use the swab result to decide whether to offer you IV antibiotics during your labour.

Only women at risk of GBS infection are screened before giving birth.

If you know you have GBS, contact your midwife or doctor if:

• your waters break
• you are less than 37 weeks and you go into labour, whether or not your waters break.

Your midwife or doctor will assess you and your pēpi. They will talk to you about how to manage your labour and treatment with antibiotics depending on your situation.

If there is a reason for you to have antibiotics during labour and you agree to this, it is best to start them as soon as possible once your labour has started. Thy will be continued until you give birth.

Penicillin is the most effective antibiotic for GBS. If you are allergic to penicillin, tell your midwife or doctor so they can offer you an alternative.

If your midwife or doctor recommends IV antibiotics but you choose not to have them, your pēpi may be at a higher risk of GBS infection. If your pēpi has GBS infection and is not treated with antibiotics, they may become seriously ill and even die.

Risks of antibiotics

Some women have a mild allergy to certain antibiotics and you may have temporary side effects such as:

• runny poos (diarrhoea)
• feeling sick (nausea).

There is a rare chance of serious allergy (anaphylaxis) to an antibiotic, which is usually treatable but can be life threatening. But for most women antibiotics are safe. Talk to your midwife or doctor about the risks and benefits of having antibiotics during labour.

Antibiotics can cause thrush (candida), mostly in the vagina. They can also cause thrush in pēpi, mostly in their mouth or on their bottom (nappy rash). Your midwife or doctor can help you treat this.

Breastfeeding

Carrying GBS does not affect breastfeeding. The antibiotics given in labour are safe for breastfeeding.

Caesarean sections

Doctors do not recommend having a planned caesarean section to prevent GBS infection in pēpi. Caesarean sections have risks for mothers and pēpi, and they do not completely remove the risk of GBS infection.

If you are having a planned caesarean section for another reason, antibiotics for GBS are not recommended. The risk of your pēpi developing GBS infection during caesarean section is very low.