10 Reasons Why Your Monthly Cycle Is Late (and You Aren't Pregnant)

Every woman is familiar with their menstrual cycle & flow. Menstrual flows usually occur every 21 to 35 days and last 2 to 7 days. And the cycle is not the same for every woman. Some might have a regular cycle (about the same length every month) and others might have irregular cycle. The flow could be light or heavy, pain-free or painful, long or short, but one usually knows what is "normal" for herself.

For those who usually have a regular cycle, here are some reason why your monthly cycle is late.

  1. Natural reasons. Other than pregnancy, these are including breast-feeding & menopause.  
  2. Contraceptive. Some women who take contraceptive pills may not have their regular cycle, even after they are stop taking the pills, as it may take some time before the regular cycle return. Injected or implanted contraceptives  could also cause the same effect.
  3. Medications. Some medications can cause menstrual cycle to stop, including antipsychotics, antidepressants, blood pressure medications, allergy medications, chemotherapy drugs.
  4. Stress. Physical & mental stress could arise from continuous-not-so-relaxing travelling, major life changes (new job, moving to a new country, relationship problem, etc), excessive physical exercise with rigorous training, sleeping problem, extreme diet, etc. Physical & mental stress can alter the functioning of hypothalamus — a brain area that controls hormones releasing such as adrenal hormones, thyroid hormones and female hormones (progesterone & estrogen). The first hormone that response to stress is cortisol,  a hormone produced by adrenal gland. When adrenal hormones imbalance persist, it could lead to imbalance of thyroid hormones  & progesterone supply. Besides missing their menstrual cycle, some women may experience some bothering complaints such as feeling anxious & sad, difficulty to focus, poor memory, tiredness, sleeping problem, headaches, etc. Regular menstrual periods usually resume after stress management.
  5. Low body weight. Excessive low body weight & low body fat interrupts many hormonal functions in your body. Women who have an eating disorder, such as anorexia or bulimia, often stop having periods because of these abnormal hormonal changes.
  6. Thyroid hormone imbalance. Excess of thyroid hormones (hyperthyroidism) or low thyroid hormones (hypothyroidism) can cause menstrual irregularities. Symptoms of thyroid hormones imbalances include difficulty losing weight, low energy, constipation, hair loss, mood & memory problem, puffy eyes, etc. 
  7. Ovarian cyst. Some women may have a condition called Polycystic Ovary Syndrome, which accompany by excess of male hormone.
  8. Excess of male hormone. Women do have male hormones (androgen) even it is a lot less compare to men. Elevated levels of male hormones may result in symptoms such as excess facial & body hair, severe acne, or baldness.
  9. Pituitary tumor. A tumor in your pituitary gland can interfere with the hormonal regulation of menstruation.
  10. Scar tissue at uterus. Scar tissue at the uterus can sometimes occur after procedures such as curettage, cesarean section or treatment for uterine fibroids. The scar tissue prevents the normal buildup and shedding of the uterine lining.