Hello and welcome to ‘Ask A Doctor’ service. I have reviewed your query and here is my advice. If you are of the age that you still get your menstrual period, bleeding during an acute illness can occur from the stress of your illness on your body. Many women get irregular periods when their body is under physical stress from illness, and also from intense physical activity or rapid weight changes. So if you are of reproductive age, the bleeding is nothing to worry about. If you are menopausal, any vaginal bleeding is abnormal and is definitely not related to your illness or any medication you were given. Causes of vaginal bleeding after menopause can include uterine cancer, so it is important to be evaluated fully if you are in that age group. So in summary, severe illness can affect your menstrual cycle and cause irregular bleeding if you are of reproductive age. However, if you are post-menopausal, vaginal bleeding is not normal and should be evaluated by a gynecologist. I hope I was able to adequately answer your question today and that my advice was helpful. Let me know if I can assist you further. Best wishes, Dr. Brown