Vaginal discharge test for Group B Streptococcus Infection (GBS)

Blood tests, vaginal discharge tests and ultrasound tests are used in screening for
pregnancy and as part of your prenatal care.
Please refer to “Examples of Maternity Checkups”
Rubella is one of the items assessed by a blood test and GBS is done by a vaginal
discharge test.

Group B Streptococcus Infection (GBS)

When vaginal discharge tests are performed on pregnant women, 2 to 30% test positive to GBS.
At this hospital, the culture test is performed between the 30th and 33rd week of pregnancy.
Death can occur from either of the two types of GBS infection; early –onset GBS infection occurs within a week (seven days) of delivery and late-onset GBS infection occurs after seven days or more from the time of delivery.

It is estimated that around 100 to 150 newborns die each year due to GBS infection. It is also estimated that newborns from approximately one out of every 2000 to 3000 deliveries will develop a GBS infection.
Because the infection can be transmitted from mother to child (transbirth canal infection), the newborn may develop problems such as: pneumonia, sepsis, meningitis and other serious complications (mental retardation, hearing or visual impairment), or even death.
When a pregnant woman who is GBS positive is admitted to the hospital in labor, she will be prescribed IV antibiotics administered on a schedule until the time of delivery.
According to studies, this preventive IV drip decreases the chance of early-onset GBS infection to one-third.

However, the preventive IV drip does not reduce the chance of late-onset infection.
If a baby is infected with late-onset, he/she may display symptoms after being discharged from hospital. If your baby appears feverish, weak or listless, please contact the maternity ward.

page last reviewed: April 1st, 2019