Picture, if you will, your typical sleep apnea sufferer. Chances are he is middle-aged and overweight and snores like a freight train. Note the male pronoun. Twenty-five years ago experts believed that the condition, in which breathing is disrupted during sleep, was about 10 times as common in men as in women. Better-quality studies have since reduced that ratio to roughly three to one, but as more data come to light, it is becoming clearer that sleep apnea—and the broader category known as sleep disordered breathing—simply looks a little different in women. And that suggests it is often overlooked.