Methodology: Six hundred pregnant women aged from 20 to 40 years old with singleton living healthy fetuses undergoing elective lower segment caesarean section (LSCS).They will be randomized into three groups: group A in which 200 women will receive IV ceftriaxone (2g) 60 minutes before skin incision, group B in which 200 women will receive IV ceftriaxone (2g) immediately with skin incision & group C in which 200 women will receive IV ceftriaxone (2g) immediately after umbilical cord clamping. Outcomes include postoperative maternal & fetal infectious morbidity.