Hi Gracie.

Basically a bug has been found in vagina, which causes no harm to you, but seeing as you will be having a bubs travelling down that region soon, they need to protect bubs. Babies in womb are in protected environment, however, they may pick up the bug on their skin during birth process.
Intravenous anitbiotics will be given to you during labour so bubs doesnt catch anything.... docstors and midwives will prob observe your baby for symptoms after birth, but really its just a precaution......