Medical Conditions Heart disease, diabetes, or premature menopause can affect the onset and nature of menstruation. In addition, hormonal conditions can affect menstruation - certain hormones, such as prolactin or thyroid hormones, can cause delayed or absent menstruation. If this is the case, the condition can be diagnosed with a blood test. In general, it is important that a condition of hormonal imbalance and the reasons for it, be consulted with the doctor. Polycystic Ovary Syndrome Irregular menstruation is a symptom of polycystic ovary syndrome , in which many cysts (small sacs filled with clear fluid) develop in a woman's ovaries. In women suffering from the syndrome, ovulation will usually not occur at all, and the hormonal imbalance will be abnormal until appropriate treatment is received. Stress Stress is absolutely one of the harmful signs of modern life. It is a condition that can cause hair loss, lack of sleep , depression, skin problems , and weight fluc...