Background: Most of cesarean deliveries are performed with regional anesthesia especially spinal anesthesia (SA). Disadvantages of SA include maternal hypotension and fetal asphyxia. This study was conducted to find prophylactic strategies for prevention of maternal hypotension in the women who were candidate for cesarean in Rasht Azzahra Hospital in 2001. Materials and Methods: This study was a double blind randomized clinical trial that was done on 96 women who were candidate for elective cesarean section. The patients were randomly divided into four groups (24 patients in each group). They received either Saline (control), intramuscular Ephedrine 30 mg [IME] 15 minutes before SA, intravenous Ephedrine 30 mg [IVE] one minute after SA and intravenous Atropine 0.5 mg [IVA] one minute after SA. Blood pressure, pulse rate (PR) and SaO2 were determined before SA and then with 3 – 5- minute intervals until 40 minutes after SA. Severe hypotension was defined as more than 30% decrease in systolic blood pressure or less than 90 mmHg in patients with normal blood pressure. SA was done with 5% Lidocaine. Statistical analysis was done using Chi-square test and variance analysis. Results: The prevalence of severe hypotension was 21% in IME, 17% in IVE and 37.5% in IVA and 42% in control group. Their difference was statistically significant only in IVE (P<0.05). IME group had more tachycardia than other groups probably due to higher prevalence of mild hypotension. Ephedrine IV had not any adverse effect on maternal PR, neonatal PR and APGAR score. Conclusion: Prophylactic administration of Ephedrine 30 mg IV during one minute after SA is useful for the prevention of severe hypotension in cesarean deliveries and these patients had more hemodynamic stability. Administration of this drug had not any adverse effect on maternal PR, neonatal PR and APGAR score.