Some of the most common causes of delayed menstruation are hormonal imbalances, illnesses, changes in medications and menopause or pregnancy. Excessive exercise, rapid changes in weight, being either overweight or underweight and a poor diet can also contribute to irregular menstruation. A normal menstruation cycle is different for each woman, because some women menstruate as often as every 20 days and others menstruate only every 35 days. The length of the cycle also varies for each woman and can last from three to seven days.
Hormonal imbalances are a common cause for a delayed cycle. A common hormonal disorder is known as polycystic ovarian syndrome, and it can contribute to irregular menstruation or a missed period altogether. Emotional stress, anxiety, fatigue and hormone replacement therapy are some of the most common factors that interfere with the hormone levels. An interference also can be caused by a foreign substances in the body, such as environmental pollutions, chemicals, cigarette smoke and excessive use of certain cosmetics. Pregnancy and breastfeeding also are common causes of delayed menstruation.
A poor diet high in saturated fats, processed foods and many junk foods can deprive the body of the necessary nutrients that it needs to balance the hormone levels. Unhealthy changes in the diet and eating disorders can lead to rapid weight loss or rapid weight gain, both of which can interfere with the menstruation cycle. Excess weight in general tends to interfere with the hormones and thus is a major risk factor for delayed menstruation. Exercise can help one maintain a healthy weight, but it should be done in moderation, because regularly engaging in vigorous exercise interferes with the cycle as well.
Delayed menstruation also can be caused by certain medications, such as birth control pills, antidepressants and corticosteroids. It can take the body several cycles to readjust to the new amount of hormones in the body when a woman is going on or coming off birth control pills. Changes in other medicines also can result in delayed menstruation. Other common causes include an acute or long-term illness such as thyroid disease, a brain or pituitary tumor, infections and premature ovarian failure.
Perimenopause is the stage just before menopause in which the body begins to reduce the production of hormones. During this time, the cycles begin to change. This often results in a light or heavy cycle, a late period or a long menstruation cycle.