A woman's menstrual cycle typically follows a 28-day cycle, ending when the lining of the uterus is shed and bleeding occurs. Because the menstrual cycle signifies a woman's hormones are properly working, having a menstrual cycle is important to signify the body is in good health. However, a number of conditions and problems can interfere with a woman's ability to experience a normal menstrual cycle, which is known as amenorrhea. Contributing factors, such as pregnancy, sudden weight loss, overexercising, medical conditions and even stress can all contribute to a missed period, or several missed periods.
Effects of Stress
When a body is placed under constant and/or excessive stress, the body secretes the stress hormones adrenaline and cortisol. Adrenaline gives you more energy, such as the final push to stay up late to study; cortisol increases brain function and slows or stops functions the body considers nonessential. Some of these include cellular growth and the digestive process--and another factor is suppressing the reproductive system.
When the body produces too much cortisol, the areas of the brain identify reproductive functions--such as the menstrual cycle--as being unnecessary during a stressed response. Cortisol signals the brain to stop releasing reproductive hormones estrogen and progesterone. Both of these hormones are necessary to stimulate the menstrual cycle. Without them, the menstrual cycle cannot occur.
Stress doesn't necessarily result in the total cessation of a menstrual cycle. Depending upon a woman's unique hormone cycle and stress levels, stress can have a number of effects, ranging from onset of bleeding before a period to less bleeding than normal to a shorter period. These occurrences don't allow the body to thoroughly carry out its functions. If the stress is significant enough to affect menstruation, it's likely it's also enough to hinder other bodily functions. Therefore, it's important to keep stress levels low in order to help the body return to normal functioning.