Final answer:
Prophylactic antibiotics are used to prevent Group B streptococcal infection in newborns and prevent infection after surgical procedures. Chest physiotherapy is not typically used to prevent the mentioned conditions.
Step-by-step explanation:
Prophylactic antibiotics and chest physiotherapy are used in medicine to prevent certain conditions in pregnancy and after surgical procedures. Prophylactic antibiotics are commonly used to prevent Group B streptococcal infection in newborns and to prevent infection after surgical procedures. Chest physiotherapy, on the other hand, is not typically used to prevent respiratory distress syndrome, preeclampsia, or gestational diabetes.