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RCOG release: Women in preterm labour to be offered antibiotics to combat Group B Strep

News 13 September 2017

Women who go into labour before 37 weeks of pregnancy should be offered antibiotics to prevent a possible transmission of Group B Streptococcal (GBS), according to updated guidance published today (13 September) by the Royal College of Obstetricians and Gynaecologists (RCOG).

This is the third time the Green-top Guideline has been revised since 2003 and will provide further guidance for obstetricians, midwives and neonatologists on the prevention of early-onset neonatal GBS. The guidance also calls for all pregnant women to be provided with appropriate information about GBS to support decision making and to raise awareness of the signs and symptoms of the infection in babies.

GBS is the most frequent cause of severe early onset (less than 7 days of age) infection in newborn babies. It is a bacteria that occurs naturally in the digestive system and lower vaginal tract of around a quarter of women at any one time and normally causes no harm. For pregnant women who carry GBS, the bacteria can be passed onto their baby during labour. The vast majority will suffer no ill effects but a small proportion of these babies will develop an infection and can become seriously ill.

Incidence of early onset GBS appears to be rising in the UK and around 500 babies developed the condition in 2015. With prompt treatment, 17 out of 20 diagnosed babies will fully recover, however, two in 20 babies with GBS infection will recover with some level of disability, and one in 20 infected babies will die.

Women are at higher risk of passing GBS onto their baby if they go into preterm labour with nearly a quarter of all cases of early onset GBS in 2015 (22%) in babies born prematurely.  Compared to a risk of one in 2000 for babies born at term, approximately one in 500 preterm babies will develop EOGBS disease. The mortality rate from infection increases from 2-3% for at term babies to 20-30% for those born before 37 weeks.

For this reason, the RCOG guideline now recommends all women who go into preterm labour, regardless of whether their waters have broken, receive intravenous antibiotics during labour to prevent onset of the GBS infection.

Other risk factors for EOGBS include having a previous baby affected by GBS, a positive test for GBS discovered incidentally during pregnancy, prolonged rupture of membranes and a temperature of more than 38 degrees during labour. The updated guidance also advises that women who were known carriers of GBS in a previous pregnancy can be offered a test at 35-37 weeks of pregnancy to see whether they are still a carrier, in order to reassess whether they still require antibiotics during labour.

The revised guideline does not recommend universal bacteriological screening for GBS, in line with recommendations made by the National Screening Committee. It found that there is no clear evidence to show that routine testing would do more good than harm.

Professor Peter Brocklehurst, Professor of Women’s Health at the University of Birmingham and a co-author of the guideline, said: 

“This guidance provides clear advice to doctors and midwives on which women should be offered antibiotics to avoid passing GBS infection onto their babies. In particular we hope to reduce the number of early onset Group B Strep infections and neonatal deaths in babies born before 37 weeks.

“The management of women whose babies are at raised risk of developing Group B Strep infection remains a vital part of reducing illness and deaths caused by this infection. Ensuring a consistent approach to care in all maternity units is vital to achieving the best outcomes for both mother and baby.” 

Professor Janice Rymer, Vice President of Education for the RCOG, said:

“Research by the RCOG in 2015 found a large variation in UK practice about how best to prevent early onset GBS disease. This revised guideline will provide standardised treatment of pregnant women with GBS and reduce the risk of their babies developing the infection. The guideline also aims to raise awareness of GBS by recommending that all pregnant women are provided with an appropriate information leaflet, which the RCOG is now updating in line with this new guidance.”

Jane Plumb, Chief Executive of Group B Strep Support

“We welcome this major update to the RCOG's clinical guidance which represents a significant improvement in the procedure to prevent Group B Strep infection in newborn babies. When fully implemented across the UK, we believe this change will make a real difference and we will see the rate of infections start to fall.

“We are delighted that the guideline recommends all pregnant women are provided with an information leaflet on GBS. Group B Strep Support has been working closely with the RCOG to develop this leaflet, which will significantly improve the quality and regularity of information on GBS. We are confident that this increased access to clear, concise information will play a vital role in raising awareness of GBS and empowering women to make informed decisions throughout their pregnancy and in the early days after birth.”



For more information and an embargoed copy of the Green-top Guidance, please contact the RCOG press office on 020 7045 6357 or email

Hughes RG, Brocklehurst P, Steer PJ, Heath P, Stenson BM on behalf of the Royal College of Obstetricians and Gynaecologists. Prevention of early-onset neonatal group B streptococcal disease. Green-top Guideline No. 36. BJOG 2017; DOI: 10.1111/1471-0528.14821.

RCOG patient information leaflet Group B Strep infection in newborn babies [currently being updated with Group B Strep Support and due for publication later this year].

For further information on why screening for GBS is not recommended in the UK, see information from the National Screening Committee.

Signs and symptoms of early-onset neonatal infection

Parents and carers should seek urgent medical advice if they are concerned that the baby:

  • is showing abnormal behaviour (for example, inconsolable crying or listlessness)
  • is unusually floppy
  • has developed difficulties with feeding or with tolerating feeds
  • has an abnormal temperature unexplained by environmental factors (lower than 36°C or higher than 38°C)
  • has rapid breathing
  • has a change in skin colour.

Case study:

32 year old Rebecca Gunn from Wakefield, Yorkshire (photos available on request)

“In 2015, I gave birth to my daughter, Hannah, after a healthy and straightforward pregnancy, so I was surprised to find out that I had Group B Strep during my second pregnancy earlier this year. I had gone in to hospital after experiencing some bleeding at 17 weeks and that is when they picked up that I was a GBS carrier.

“The diagnosis came out of the blue. I was really surprised as GBS hadn’t even crossed my mind. Afterwards, my main concern was around the birth and what my options would be. I was disappointed to learn that I wouldn’t be able to give birth in a midwife-led unit, like I had with my daughter, but obviously I understood the reasons for it. I didn’t want to take any risks.

“In June this year my waters suddenly broke at 38 weeks and I was rushed onto the labour ward where I was induced and given antibiotics. As I had previously said that I wanted to give birth on the midwife-led unit, staff on the labour ward were very accommodating. They let me listen to my music, brought me tea and toast and offered me the birthing ball and the chance to move around – which was very difficult because I was on a drip! Midwives were friendly and let me do whatever I wanted to do, putting me at ease. It was a much more positive experience than I had been expecting.

“I gave birth to a healthy baby boy called Alistair. He was monitored for 24 hours and received three lots of antibiotics due to the length of labour, and was fortunately unaffected by GBS.

“I think the RCOG’s revised guideline will help to raise awareness of GBS among pregnant women and new mothers. I had a straightforward birth with my daughter, no complications, but I could have been a carrier then too and I wouldn’t have known. I knew nothing about GBS. I’m not saying this to scare people, but it’s important they are informed and aware of the risks. 

“My GBS only got picked up by chance during my second pregnancy and there was part of me that thought, if I didn’t know I wouldn’t have had this battle about what to do in terms of where to give birth and I probably would have been fine. But then it was a positive thing that this did get picked up because I had the chance to have antibiotics and reduce the risk of transmission. 

“Ultimately, this guideline is about giving women the choice and empowering them to make decisions."