Certainly, here are 10 common causes of delayed menstruation: 2. Stress: High stress levels can disrupt hormonal balance, leading to irregular cycles. 3.Weight Fluctuations**: Rapid weight gain or loss can affect your menstrual cycle. 4. **Illness**: Chronic illnesses, like polycystic ovary syndrome (PCOS), can lead to irregular periods. 5. **Medications**: Certain medications, including contraceptives, may impact menstrual regularity.