AbstractBackground and aims: Inferior venacaval compression during pregnancy causes extradural venous engorgement which may reduce the lumbar cerebrospinal fluid volume. A subsequent greater cephalad spread of sensory block is observed. We hypothesized that maternal abdominal circumference measurement can reflect the compressive effect of uterus and investigated the relationship between maternal abdominal circumference and the level of sensory block, the maximum level of sensory block, incidence of hypotension, nausea, vomiting, requirement of ephedrine in term parturients undergoing cesarean section under spinal anasethesia. Methods: Abdominal circumference of 40 term parturientswere measured before performing subarachnoid block. 0.5% hyperbaric bupivacaine (2ml, 2.2ml, 2.4ml) was injected into L3-L4 subarachnoid space according to parturients height .The level of sensory block was assessed at various time intervals. The statistical tests applied were Onewayanova, product moment correlation and independent sampleT Test. Results: The correlation coefficient between abdominal circumference and the level of sensory block was significantly positive at various time intervals (p<0.05) following spinal anesthesia. There was a positive correlation between abdominal circumference and highest level of sensory block. No significant correlation was found between abdominal circumference and incidence of hypotension, requirement of ephedrine, nausea and vomiting after spinal anaesthesia (p>0.05).There was a significant positive correlation between BMI and the level of sensory block (p<0.05). Conclusion: Parturients with greater abdominal circumference value have a higher level of sensory blockade after spinal anaesthesia. Abdominal circumference cannot predict the incidence of hypotension, nausea, vomiting and the dose of ephedrine required.