To understand factors that may contribute to individual differences in menstrual symptom experience. This information is crucial for developing interventions to manage menstrual symptoms effectively. Many people who menstruate experience symptoms such as cramps, low back pain, or changes in bowel frequency. However, we still don’t fully understand why these symptoms vary from person to person. By collecting blood, menstrual/vaginal fluids, urine, and stool samples, and learning about diet and symptoms, we aim to uncover the causes of these menstrual symptoms.