After failing to convert five match points, the world number one, who appeared to be suffering from a minor panic attack, left the court for nine minutes before returning to seal a 6-1 6-4 victory.
Stephens, who has not called for the on-court trainer during her entire career, has been delayed by her opponent taking a timeout in each of her last three matches.
When asked by Australianopen.com if she thought that the system was being abused, she replied: "No, I don't think so.
"There's a certain thing in the locker room that tells you like if you take more than six [timeouts] a year or something that they'll start charging you. That's a good rule.
"But the whole time I've been on the WTA Tour I've never had a medical timeout, so I don't know how it feels. I don't know what they do. I don't even know what you say."