Primary dysmenorrhea (PD) is characterized by menstruation with painful periods in women without pelvic organ damage. It constitutes a gynecological dysfunction that manifests itself with pain in the lower abdomen, which may radiate to the paravertebral region and thighs. PD pain can impair activities of daily living (ADLs) and affect women's behavior, even causing anxiety and depression.

To assess PD and mood disorders (anxiety and depression) in young nulliparous women and identify their associations.

A descriptive, observational, cross-sectional study was carried out with a convenience sample of young nulliparous women. Women aged between 18 and 30 years, who had never been pregnant and were not taking medication to treat mood disorders, were selected. The participants were evaluated by the same examiner using the socio-clinical questionnaire, visual analogue pain scale (VAS) and hospital anxiety and depression scale (HADS). In the data analysis, the averages and standard deviation of the variables were calculated, according to the distribution of the sample's normality, and the groups with and without PD were compared using the t test for independent samples, and the correlation analysis between PD, anxiety and depression by Pearson's correlation coefficient (R). Data were analyzed using the Statistical Program for Social Sciences (version 23) considering a significance level of 5%.

The sample consisted of 69 nulliparous young adult women with a mean age of 21.86 ± 3.16 years. The prevalence of PD was 65.21% (n=45) and from this group, 35 participants reported that PD affected their performance in ADLs. The level of dysmenorrhea pain was low, with an average VAS of 3.59 ± 3.16 points. Most participants mentioned a regular menstrual flow and average pain of 3.59 ± 3.16 by VAS. In the characterization of behavioral aspects, a prevalence of 59.42% (n=41) was identified in screening for anxiety and 23.18% (n=16) for depression. There was no statistically significant difference between the groups with and without PD regarding mood disorders, although the group with PD had higher values ​​for such disorders. There was a weak direct correlation between anxiety and PD (R=0.30) and a moderate direct correlation between depression and PD (R=0.33).

PD and mood disorders are prevalent among young nulliparous women. Women with PD do not have more mood disorders compared to women without PD, however women who have PD, anxiety and/or depression tend to have higher levels of mood disorders concomitantly.

In scientific terms, women who have PD concomitantly with anxiety and/or depression tend to have higher levels of PD and mood disorders, which may negatively impact their lives. In clinical terms, this study demonstrates the importance of the professional's appreciation of the assessment of dysmenorrhea and mood disorders that can influence clinical therapeutic practice.