You were expecting your monthly visitor, your Aunt Flo, your little friend, or whatever you like to call her, but she hasn’t arrived. Besides the obvious reason for a late period, what could be causing your period to be late? There are plenty of reasons why your period might be delayed that do not include pregnancy. Here are 11 of the most common reasons for a late period.
The typical menstrual cycle is 28 days long. If you have a regular cycle, your period may come every 28 days like clockwork. However, having a regular cycle is no guarantee that your period will always arrive when expected. Since the time of ovulation can vary from month to month, it’s possible that this month you ovulated a little later than you normally would have, and your period is not actually late, even though it seems like it is. In addition, if you don’t keep track of your cycles, it’s easy to mix up the date of your last period, and thus miscalculate when to expect your next one.
You may have heard that stress can delay your period, and stress is in fact one of the most common causes of a missed period. Usually when stress delays your period though, it is because you were under stress around the time you would have ovulated. If ovulation is delayed, your period, which normally comes 14 days later, is also delayed. Stress around the time of your period does not normally make your period late – or not very late – provided that you ovulated when you normally do. Worrying can cause your period to be a day or two late, but it won’t push your period out much later than that. If you ovulated around the time you normally do, your period should arrive within 14 to16 days after ovulation, whether you are under stress or not.
Like stress, illness can also make your period late. If you are ill around the time you would have ovulated, this may keep you from ovulating or temporarily delay ovulation. If ovulation is late, your period will be late as well. If your period is late, think back to how you were feeling a couple weeks earlier. If you were sick, this could very well explain why your period hasn’t showed up.
Having an eating disorder or being underweight can disrupt your menstrual cycles or cause them to stop all together. It was once thought that anorexia nervosa was the only eating disorder that caused menstrual irregularities, but newer studies have found that any eating disorder can cause problems with menstruation. When a woman doesn't have enough body fat, her body has a hard time making the necessary estrogen to support ovulation. If you aren't ovulating, you won't have a period or your periods will become irregular.
Being overweight can disrupt your menstrual cycles. Your ovaries produce estrogen, but body fat is also a source of estrogen. When a woman has low body fat she doesn't produce enough estrogen, but when she is overweight she may produce too much estrogen. Estrogen and progesterone work together to maintain a healthy menstrual cycle. Normally during the first half of your cycle estrogen levels increase until they reach a certain threshold. When your estrogen levels reach this threshold, it triggers ovulation. When your body has a steady flow of estrogen though, your body doesn't differentiate the high estrogen level as an ovulation trigger because your estrogen levels are always at a higher level. This interferes with ovulation. If you aren't ovulating regularly, your cycles can become sporadic and unpredictable.
PCOS, or Polycystic Ovarian Syndrome, is a disorder that is caused by having excessive male hormones. All women produce some male hormones (or androgens) but women with PCOS produce higher levels of androgens. This can cause the ovaries to malfunction and keep her from ovulating. Normally during ovulation a woman will produce several follicles, but one will become the dominant follicle that is released during ovulation. Women with PCOS instead produce many small follicles, but because of the extra androgens none of them fully mature. Because she is not able to ovulate, her cycles may become irregular.
It is fairly common for women with thyroid disorders to have issues with ovulation and irregular menstrual cycles. Doctors aren't clear on why the thyroid causes problems with the menstrual cycle. Sometimes women with thyroid disorders don't ovulate or if they do they may have a weaker ovulation and shorter luteal phase. Anything that interferes with normal ovulation can cause your period to be late or to become irregular.
Every woman is born with around 1 to 3 million eggs. Every time she ovulates she releases one of these eggs. She also loses some of her eggs as she ages. Some of them die. Some of them get old and are no longer quality eggs. When she no longer has any quality eggs, she stops ovulating, and in turn stops having a period. For most women this happens sometime around the age of 45. Sometimes this will happen earlier than expected. When a woman stops having a period before she turns 45 it is referred to as early menopause; if she stops having a period before 40 it is called premature menopause.
Change in Schedule
Anything that puts stress on your body can cause ovulation to be delayed. If you start a new job, travel, or change your wake-up time, it may take your body a little while to adjust to the change. If the change in routine took place around when you would have ovulated, it may stop ovulation or push your ovulation date back. If this happens, your period will be delayed or you might even skip a cycle.
Being an Athlete
Endurance athletes and women who exercise excessively sometimes stop having a period, even if they are at a healthy body weight. A demanding exercise program puts a lot of stress on a woman's body. When this happens her body may stop menstruating as a way to conserve energy. Additionally, women who exercise a lot may have extremely low body fat. Without body fat, a woman's body can't produce enough estrogen to ovulate.
Most hormonal birth control contain synthetic versions of the hormones estrogen and progesterone. By altering your hormone levels, birth control stops ovulation, changes the quality of your cervical mucus, and thins your uterine lining which makes implantation difficult. After you have taken birth control for a while your lining may become thinner, your period may become lighter, or you may stop having a period altogether. Some birth control methods will keep you from having a period, or will reduce the frequency of your menstrual cycles. Moreover, during the first few cycles on birth control, your menstrual cycle may take a while to adjust. This may cause your period to be delayed.