GBS positive. membrane sweep?

Told I was GBS positive. This is my third pregnancy and had never heard of it until a few weeks ago. I have read so many stuff online and I am scared. Doctor told me she wants to do a membrane sweep. But iv read not to do it that baby has higher risk of getting infected? What do you do if your water breaks before you get to the hospital? How long do you have to get antibiotics? Also, when you get to the hospital do you let them check your cervix? Wouldn't that not be a bigger risk for baby?