Neuroaxial anesthesia has long been accepted as the standard practice for providing the safest anesthesia for cesarean section .Spinal anesthesia for CS should ideally last the duration of the procedure without producing maternal or fetal adverse effects. This study is to monitor the two techniques during cesarean section, fixed dose of bupivacaine not tailored to patient height and variable dose of bupivacaine tailored to patient height. We will compare the outcomes from the two different techniques regarding the level of anesthesia achieved, resulting hemodynamics (BP & HR) ,the requirements for fluids & pressors ,development of nausea & vomiting and the time needed to discharge from PACU. This study was conducted on 80 patients aged between 20 and 40 years old, ASA grade I and ІІ . All patients were scheduled for elective cesarean section surgery. All cases were done in Benha university Hospitals after approved consent from the patients. The duration of sensory and motor block was significantly prolonged in fixed dose groups (A&C) than in adjusted dose groups (B&D).The amount of fluids and vasopressors needed were significantly much more in fixed dose groups (A&C) than in adjusted dose groups (B&D).The incidence of complications (hypotension , nausea and vomiting) were significantly higher in fixed dose groups (A&C) than in adjusted dose groups (B&D).we have shown that adjusting the dose of hyperbaric bupivacine (0.5%) according to height in both normal and pre-eclamptic patients , in combination with opioids (fentanyl 20 mcq) , provide adequate anesthesia for elective cesarean section in both normal and pre-eclamptic patients. This regimen associated with decrease in cephalic spread of anesthesia, decrease incidence and severity of maternal hypotention ,nausea ,vomiting , decrease the amount of fluids needed and the dosage of vasopressors used.