Causes
By Mayo Clinic staffMany healthy people carry group B strep bacteria in their bodies. Group B strep bacteria aren't sexually transmitted, and they're not spread through food or water. You may carry group B strep in your body for just a short period of time, they may come and go, or you may always have them.
Some individuals, such as older adults and those with chronic health conditions, can develop a more serious infection from group B strep. However, the reason this occurs in some people but not others isn't known.
Group B strep can also spread to a baby during a vaginal delivery if the baby is exposed to — or swallows — fluids containing group B strep.
From the AMERICAN PREGNANCY ASSOCIATION
Group B streptococcus (GBS) is a type of bacterial infection that can be found in a pregnant woman’s vagina or rectum. This bacteria is normally found in the vagina and/or lower intestine of 15% to 40% of all healthy, adult women.
Those women who test positive for GBS are said to be colonized. A mother can pass GBS to her baby during delivery. GBS is responsible for affecting about 1 in every 2,000 babies in the United States. Not every baby who is born to a mother who tests positive for GBS will become ill.
What if I test positive for Group B Strep infection?
If you test positive for GBS this simply means that you are a carrier. Not every baby who is born to a mother who tests positive for GBS will become ill. Approximately one of every 100 to 200 babies whose mothers carry GBS will develop signs and symptoms of GBS disease. There are, however, symptoms that may indicate that you are at a higher risk of delivering a baby with GBS. These symptoms include:
- Labor or rupture of membrane before 37 weeks
- Rupture of membrane 18 hours or more before delivery
- Fever during labor
- A urinary tract infection as a result of GBS during your pregnancy
- A previous baby with GBS disease
In this case your physician will want to use antibiotics for prevention and protection.
According to the CDC, if you have tested positive and are not in the high risk category, then your chances of delivering a baby with GBS are:
- 1 in 200 if antibiotics are not given
- 1 in 4000 if antibiotics are given