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From £50
Lab fee only

Group B Strep screening

35 - 37 weeks

At a glance

A Group B Strep (GBS) screening checks for the presence of a harmful bacteria that causes life-threatening infections in newborn babies.

Please note: we no longer offer this as a stand alone service, it is now only carried out (at a discounted fee) along with a Presentation scan.

  • Performed with a Presentation scan
  • No GP referral required
  • Screening not routinely available on the NHS
  • Same or next day appointments
  • Weekday, Thursday evening or Saturday clinics
  • Convenient central London location

You will receive

  • Your results in 72 hours

What happens with your results?
We will call you with your results, which will be available 48 hours after your appointment.

What is it?

GBS (or Group B Streptococcus) is a bacteria that is the most common cause of life-threatening infections for newborn babies in the UK.

It tends to develop later in pregnancy and therefore the screening is best performed no earlier than 35 - 37 weeks.

Who carries the bacteria?

In total, 30% of the population carry GBS harmlessly and naturally in their digestive system.

Out of all pregnant women in the UK, one in four unknowingly carry the bacteria in the vagina, where it can be passed on to their baby during childbirth.

The bacteria can also be transmitted during births by caesarean section.

The risks of carrying GBS

If you are infected with GBS and it is transferred during childbirth it can cause serious complications to your baby, including:

  • Pneumonia (infection of the lungs)
  • Meningitis (infection of the lining of the brain)
  • Septicaemia (blood poisoning)

One in five babies who survive the infection will be permanently affected with problems, such as cerebral palsy, deafness, blindness and serious learning difficulties.

One in 10 babies diagnosed with early-onset GBS infection will die. However, most babies who do become infected in this way can be treated successfully and will make a full recovery.

GBS can sometimes affect the mother as an infection in the womb or urinary tract and with a more serious infection, sepsis, which spreads through the blood, causing symptoms to develop through the whole body.

Can I be screened for GBS on the NHS?

In the UK GBS screening is not generally available on the NHS, although within the USA all mothers are offered GBS screening at 36 weeks.

What happens during the screening?

Two separate swabs are taken and sent to the laboratory for analysis. One is taken from the lower region of the vagina and one from the anus.

The swabs are long, thin, sterile sticks similar to cotton buds, and are only inserted 2 - 4cm into the vagina and 1 - 2cm into the anus. The sampling process is quick and not uncomfortable.

The results are available within two working days. We will call you with the result and, if requested, forward a copy of the report to your midwife, obstetrician or GP.