Sleep-disordered breathing (SDB) consists of episodes of periodic obstructive or central sleep apnea and partial upper airway obstruction. The first two are well recognized and diagnosed, although still underdiagnosed. Traditionally, research in SDB has focused mainly on male patients with obstructive sleep apnea using apnea/hypopnea index (AHI) as a measure of severity. This has led to overrating of AHI as the only marker of SDB and underestimating of SDB in women. However, recently, partial upper airway obstruction has been acknowledged to be pathological and it may cause symptoms of SDB. There is a growing body of evidence that women suffer from SDB more than thought before and they especially have partial upper airway obstruction. Co-morbidities such as cardiovascular diseases seem to be more prevalent in patients with SDB. This commentary points out some differences of SDB between genders in terms of symptoms and findings and emphasizes the clinical relevance of partial upper airway obstruction, especially in women.