What is GBS (Group B streptococcus)

GBS is a bacterium that often harmlessly lives inside a person’s intestines. In about 10 to 30% of pregnant women, it is also found in the vagina and rectum, where it can pass to the baby during labor and birth. When a woman has GBS, as detected in her vagina and rectum, it can cause an infection in the newborn that can cause permanent damage, or even death. We test for GBS during pregnancy because there are steps that we can take to prevent the transmission of GBS to your baby, if you are infected. The treatment significantly reduces the chance that the baby of a GBS positive mom will develop a dangerous infection. (Information from Anne Frye’s Understanding Diagnostic Tests in the Childbearing Year, pp 743-760)

About the test

To test for GBS, we will have you lie on the examining table, undressed from the waist down. Then, we will use a swab (a large q-tip) to collect a sample from your vagina and your rectum, by placing the swab about 1.5cm into your vagina, and then just past your anal sphincter, and twirling it around for about 30 seconds. Women do not usually find this painful. We will send the specimen to the lab to be tested for the presence of GBS. (Information from Anne Frye’s Understanding Diagnostic Tests in the Childbearing Year, p 745)

Implications of a positive GBS test

The chance of infection, though hard to test, seems to be about 10 babies per 1000 babies born to infected mothers (0.01%).  A baby who develops a serious GBS infection risks permanent damage, and between a 2 and 10% of sick babies die (0.0002%-0.0010% of all babies born to infected mothers.)

In untested women, babies seem to have about a 3 in 1000 (0.003%) chance of developing an infection, with between 2 and 10% of those babies dying (0.00006% – 0.0003% of all babies born to untested women.)

Treatment Options

If you test positive for GBS, you have several treatment choices:

1)    Receive antibiotics during labor to reduce or eliminate GBS

• Reduces the serious infection rate by up to 70%
• Chance of allergic reaction to antibiotics for both mom and baby
• Some authorities have expressed concern about newborns missing out on healthy exposure to normal human flora, which is beneficial to them in many ways.

2)    Use natural remedies to try to reduce or eliminate GBS from the vagina and rectum.

• Chance of allergic reaction, depending on remedy
• No known negative side-effects to baby.
• Poorly studied, results unclear.

3)    Do nothing.

• No improvement in risk to baby
• Overall risk to baby very small

You may choose any or all of these options, choose a different option not presented here, or a combination.  (Information from Anne Frye’s Understanding Diagnostic Tests in the Childbearing Year, pp743-760)

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