Randomization and masking
®
Eligible parturients were randomized into one of three groups using a web-based tool (OS-1® contains water, glucose, and electrolytes and is packaged in a 500-mL plastic bottle; its composition is presented in Table 
OS-1® compositionBlinding of parturients was not feasible because of the taste of the drinks; instead, well-trained anesthesiologists were made unaware of patient allocation, and other study investigators analyzed the data.