Went in for my vagina exam lol I am 37 weeks pregnant and they checked to see if I'm dilating or not which I'm not. They called me later on and said I was positive for Group B, the nurse assured me it was nothing I could've done to prevent it and it just happens. And I would have to take antibiotics once I'm in labor. What does this mean? What is group B exactly? Wish they explained things to me in details. Is this harmful to me or my baby?