There are many factors that can influence the regularity of your menstrual cycle. In fact, the menstrual cycle is a very sensitive system, and can be affected by changes in your body and your environment. Some women can accurately predict their period to the day, while others wait a couple months wondering when it's going to arrive. Some irregularity for a few months at a time is usually nothing to worry about. However, if your period hasn't been regular in more than four months, it may be time to talk to a doctor.
Pregnancy should be the first cause of an irregular menstrual cycle to rule out. The most obvious change to your period during pregnancy is that it stops. This is because the body is no longer ovulating. However, there is still a possibility of spotting, even if you are pregnant, which may be mistaken for your period. If you suspect you may be pregnant, take a test to be safe.
Stress has a big impact on the many ways in which our bodies function. The menstrual cycle can be changed by chronic stress, or even just a short-term stressful event. This can explain why during finals week in college your period might be late, only adding further stress. If your menstrual cycle starts to become irregular, it could be a warning sign that you are under too much stress. You might not even realize that you are stressed out, but your body will let you know before the stress further compromises your health.
A change in diet could explain an irregular menstrual period. When your diet drastically changes, for better or worse, your body will react by preserving energy. One way it can preserve energy is by ceasing menstruation. Once your diet balances out and you are eating healthful meals, your menstrual cycle should even out. Consuming too few calories can lead to menstrual irregularity and sometimes you will stop menstruating altogether. Eating disorders like anorexia and bulimia wreak havoc on all of your body systems.
Regular exercise is great for the body and can do wonders at relieving symptoms associated with your menstrual cycle. However, too much vigorous exercise can stress out the body and cause hormone levels to change. This explains why some competitive athletes stop menstruating.
When a girl goes through puberty and starts her period, it is completely normal for her cycle to be irregular for a while. The hormones are fluctuating and trying to work out their own balance. It can take months and even years for the menstrual cycle to get on a predictable schedule.
Just like during menarche, women going through menopause will experience changes in hormone levels that affect their cycle. The menstrual cycle will likely become irregular during this time. Finally, menstruation will stop altogether.
Hormonal Birth Control
Birth control methods that contain hormones (like the pill, patch and other types) often cause changes in the menstrual cycle. Though they are ultimately supposed to regulate your period, it usually take a little while before your body gets used to them and settles into a regular pattern. You may experience breakthrough bleeding for the first few months. Many factors, such as the brand and type of contraception and whether you take your pill at the same time every day can affect your cycle.