Bacterial vaginosis is a vaginal imbalance caused by an overgrowth of bacteria naturally found in the vagina. The condition often causes itching, pain and heavy foul-smelling discharge. This characteristic smell is often described as smelling like “rotten fish”. There’s no real way to miss it. Bacterial vaginosis normally heals spontaneously, though treatment using vaginal suppository, cream or antibiotics may be necessary. The infection cannot pass to the baby in the uterus. However, in rare cases, the infection can trigger early labor and the baby is born too early.
Source: - https://www.cdc.gov/std/bv/stdfact-bacterial-vaginosis.htm