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"What is Strep B and how is it contracted? How does it only affect you off and on?"

ZocdocAnswersWhat is Strep B and how is it contracted? How does it only affect you off and on?


I am days away from my due date and my midwife told me I tested positive for Strep B. She tried to explain to me that you can have it during one pregnancy and not have it another. This confuses me.


Strep B, or "Group B Strep" is something that is routinely tested for during the last few weeks of pregnancy. This is a normal bacteria that lives on the body without causing problems for the person on whose body it is living. The bacteria usually lives in the vagina or rectum. Because of constantly fluctuating patterns of bacteria in and on the body, the bacteria can sometimes be found living in these areas and at other times will disappear, only to reappear later. This process itself is normal and not something to be concerned about. The reason that we test for Group B Strep, however, is that medical studies have shown that giving birth while Group B Strep is present puts the baby at risk of serious problems, such as infections of the blood and brain. The baby comes in contact with the bacteria during a normal delivery as its head moves through the vaginal opening. Because of this risk, all mothers are screened for Group B Strep prior to delivery. If the bacteria is found, mothers are given antibiotics when they come to the hospital to deliver the baby. This kills the bacteria and eliminates the risk for the baby. Talk to your OB GYN doctor if you have further questions about this topic!

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