Approximately 80% of all women of reproductive age experience physical and/or psychological changes in the late luteal phase; i.e., the premenstrual period [1
]. Physical changes include breast swelling, fatigue, headache, and weight gain. Psychological changes include depressive mood, irritability, and tension. These changes remit after the onset of menstruation and are commonly called premenstrual syndrome (PMS). However, PMS has a broad concept and varies in severity. In the International Classification of Diseases (10th
revision; ICD-10), PMS was listed as "premenstrual tension" under "Diseases of the Genitourinary System" [2
Although many women complain of mild symptoms, approximately 5% of women suffer from severe symptoms that lead to a reduction in quality of life [1
]. In the field of psychiatry, the diagnostic and statistical manual of mental disorders, 3rd
edition, revised (DSM-III-R) proposed a new diagnosis "late luteal phase dysphoric disorder (LLPDD)" in an appendix for further research [3
]. LLPDD is a severe variant of PMS and a dysphoric disorder that interferes with social and occupational functioning during the premenstrual period. Physical symptoms are not required for the diagnosis of LLPDD. In the diagnostic and statistical manual of mental disorders, 4th
edition (DSM-IV) [4
], a new diagnosis, "premenstrual dysphoric disorder (PMDD)" is listed as a criterion for further study instead of LLPDD. The PMDD diagnosis is also based on the assumption that the condition with the premenstrual symptoms is mainly psychiatric and should be separated from a condition with merely somatic complaints. Physical complaints are not mandatory symptoms to meet the criteria for PMDD or LLPDD.
The outline of the criteria for PMDD is shown in Table . Section A shows a list of symptoms. At least one of the symptoms, 1, 2, 3, or 4, is required for the diagnosis. Symptoms 1, 2, 3, and 4 are related to moods in depression. Section B shows a list of symptoms associated with disturbance in ordinary life and relationships with others. In section C, it is stated that an exacerbation of another psychiatric disorder should be ruled out. In section D, it is suggested that the diagnosis should be confirmed prospectively within at least 2 months. However, a provisional diagnosis that is not confirmed prospectively is allowed.
Table 1 Outline of PMDD criteria in DSM-IV 
Because PMDD is a proposed diagnosis in DSM-IV, PMDD is diagnosed as a "depressive disorder not otherwise specified". This indicates that PMDD is equivalent to other depressive disorders in some way. Many studies have found a correlation between premenstrual symptoms and depression. For example, women with PMDD or PMS have a greater history of depression [5
]. Lane and Francis [7
] estimated the percentage of women with a lifetime history of affective disorders who have premenstrual changes at roughly 60%. Moreover, women with premenstrual symptoms demonstrated a more severe depression than the control group [8
In most studies, premenstrual symptoms in healthy subjects have been investigated. However, studies in which premenstrual symptoms were assessed in women suffering from depressive disorders are few [5
]. One reason for this is the difficulty in defining premenstrual symptoms. If a woman with a depressive disorder experiences premenstrual symptoms, these symptoms may coexist with PMS or occur as premenstrual exacerbation (PME) of the depressive disorder. It is somewhat difficult to differentiate them. In this study, we examined the percentage of women with depressive disorders who fulfilled PMDD criteria using a self-rating questionnaire; these women may have included those with PME, as well as those with PMDD. We compared the characteristics of these women with healthy subjects with PMDD.