--- title: Stress, your history, and cortisol: what the research says ยท Niyora description: Why does this hit harder when life has been hard? How your stress system shifts across the cycle. url: https://niyora.com/research/stress-and-cortisol/ --- - [Niyora](https://niyora.com/) - [Research](https://niyora.com/research/) - Stress, your history, and cortisol [Research](https://niyora.com/research/) # Why does this hit harder when life has been hard? How your stress system shifts across the cycle, and what early hard experiences seem to do to premenstrual symptoms. 2 findings. Best evidence here: **strong**. ## Stress, your history, and cortisol - Strong PMS / cycle Your stress-hormone response changes across your cycle. Cortisol / HPA-axis reactivity shifts across menstrual cycle phases (meta-analysis) [HPA meta-analysis](https://www.sciencedirect.com/science/article/abs/pii/S0091302222000218) - Moderate PMDD If your body learned early that the world isn't safe, these weeks can land harder. Higher childhood adversity -> stronger premenstrual mood worsening + altered late-luteal cortisol [PubMed Central](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10653441/) [See all the research findings](https://niyora.com/research/), each with a link to its study. ## Keep reading [PMS anxiety](https://niyora.com/pms/anxiety/) ## Three steps for the moment it happens Niyora gives you three steps for that moment: reflect on what happened, regulate in about a minute, and respond with a clearer head. [Take the quiz](https://niyora.com/quiz/) [Get Niyora](https://apps.apple.com/app/niyora-pms-emotions/id6764561688)