Introduction There is a growing body of research showing that the menstrual cycle can affect mood, although research in those with an existing depressive disorder is still scarce. Studies estimate that 60% of women with depression experience premenstrual exacerbation (PME) of their depressive symptoms.

Aims With the TIDE study, we aim to 1) examine the feasibility of daily symptom tracking for two consecutive menstrual cycles to track PME, 2) estimate the prevalence of PME in depression in a clinical cohort and 3) examine whether PME is associated with other hormone-related mood symptoms (i.e., hormonal contraceptive side effects, peripartum depression).

Methods We aim to recruit 60 female participants aged 18 to 45, who are in treatment for a depressive episode and who have a regular natural menstrual cycle. Participants will participate in questionnaires at baseline, inquiring about demographic characteristics and previous experiences with hormonal contraceptives and pregnancy. Participants will complete retrospective menstruation questionnaires on days 1 and 10 of each menstrual cycle, as well as daily diaries for two consecutive menstrual cycles, inquiring about menstruation and mood symptoms. After completion of the diaries, participants will receive a symptom report, as well as a study evaluation questionnaire.

Results and conclusion We expect that providing the menstrual cycle overview of symptom severity will lead to increased symptom course insights in participants with PME, and that participants with PME will find it clinically relevant and significant to gain insight into symptom trajectories across the menstrual cycle.

The authors have declared no competing interest.

This study is funded by a 2024 Startstipendium grant from the Amsterdam University Fund (AUF).

I confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained.

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The details of the IRB/oversight body that provided approval or exemption for the research described are given below:

This study has been approved as a non-WMO study (nr. 2025.0018) by the Medical Ethical Committee of the Amsterdam University Medical Center.

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Study funding This study is funded by a 2024 Startstipendium grant from the Amsterdam University Fund (AUF).

Transparency and Openness statement: This study was not preregistered, nor was the data analysis plan. The study protocol, materials, data, and analytic code are available via osf.io/4f2y8.

The manuscript does not describe original data. The study protocol, materials, data, and analytic code are available via osf.io/4f2y8.

https://osf.io/4f2y8