Irregular Periods Explained: The Main Reasons Why Your Period Is Out of Whack

June 15, 2022

mightIrregular periods always seem to come at the most inconvenient times. They make women question whether or not they are pregnant, and they make it crucial to keep their purses stocked with tampons just in case “shark week” decides to make an unwanted appearance. However, having an irregular period can be a way of a woman’s body telling them something is wrong. A regular menstrual cycle occurs every 21-35 days and lasts anywhere from 2-7 days. Once a woman has been menstruating for a while, her body will get into a pattern, which is why an irregular period is usually defined by an absent period or even two periods in one month. Every woman will likely experience an irregular period at least once in her life, and although in most cases they aren’t serious, it is important to look into what is causing the irregularity. Here are a few of the most common reasons women may be experiencing an irregular period.

Stress

Stress is one of the most common underlying causes of an irregular period. The stress hormone, cortisol, has a direct impact on how much estrogen and progesterone are produced in the female body. During stressful times, women may produce too much cortisol in their bloodstream, thus causing their menstrual cycle to change. For a woman to have a normal cycle, the hypothalamus part of the brain must send these hormonal signals to the pituitary gland, which then sends signals to the ovaries and the uterus. The hypothalamus is located beside the area of the brain that controls human emotion. When experiencing an increase in stress, the neurotransmitters in these regions can shut down the signals to the hypothalamus and therefore stop the hormonal signals to the ovaries and uterus. Evolutionarily speaking, this makes perfect sense. If a woman is under a lot of stress either physically or emotionally, it is not the best time for a pregnancy, so the system decides to shut down completely.

Diet

A woman’s diet and overall weight are another probable reason for an irregular period. When consuming foods that are high in carbohydrates and gaining excess weight, the body will produce fluctuating levels of certain hormones that in turn shift when a woman ovulates. It is the same for women who lose a substantial amount of weight. Typically, for a woman to maintain a regular menstrual cycle, her body fat percentage must be at least 17-22 percent. This again has to do with the evolutionary concept that when a woman’s body is in a state of starvation, it means it is not conducive to maintaining a healthy pregnancy and growing a nurtured baby.

Exercise

A woman’s body needs sufficient energy to menstruate properly. If a woman is exercising excessively to lose weight and burning too much of her energy at the gym, there will be no energy left for her body to draw from during her menstrual cycle. One of the hormones present during a woman’s menstrual cycle - called leptin - is stored and produced in the fatty tissue. Training excessively and influencing drastic weight loss changes can decrease body fat, causing this and other hormones to drop and contributing to an irregular period.

Birth Control Pills

A woman’s body can take several months to adjust to the high level of hormones that birth control pills provide. Additionally, one of the side effects of a low estrogen birth control pill is a light or non-existent period. For many women, this is a positive side effect. However, when women decide to stop taking their birth control pills, their cycle may take a few months to operate normally again. Birth control pills do not always cause women to miss their period; sometimes it might be once a woman has stopped taking birth control that they find they have hidden hormonal problems that weren’t visible due to being on the pill.

Polycystic Ovary Syndrome (PCOS)

This condition affects five to ten percent of women between the ages of eighteen and forty-four. Polycystic Ovary Syndrome causes cysts to form on the ovaries, thus interfering with regular ovulation. Additional symptoms of PCOS include hair growth in odd places, dandruff, weight gain, and infertility. Even though PCOS is much more complicated than a missed period, the absence of ovulation is one of the most common indicators of this disorder. If ovulation does not happen, the egg is not released from the ovary, which in turn causes progesterone withdrawal not to occur, so the uterine lining never sheds. In some cases, the uterine lining continues to build under the steady impact of estrogen until it is so heavy it can no longer sustain itself, and a heavy and long period occurs.

Menopause

Similar to becoming pregnant, menopause occurs when hormone levels in the woman’s body begin to change. Typically, menopause starts when a woman is in her late fifty's, but sometimes irregular periods can occur as early as ten years before menopause begins. As a woman approaches menopause, ovulation becomes infrequent so the menstrual cycle can infrequently come as well. The reason that menopause causes irregular periods is very simple, menopause is the suspension of ovulation. Women are born with only a certain number of eggs, so at this point in life, all of a woman's eggs have been used during menstrual cycles.

Pregnancy

Pregnancy is the most obvious reason as to why a regular menstrual cycle comes to a halt. A menstrual period occurs when a prepared uterine lining fails to embed a fertilized egg. When the fertilized egg succeeds at becoming implanted in the lining and continues to grow into a baby, a woman does not continue to shed her uterine lining. Therefore, stopping the menstrual cycle for the duration of her pregnancy, and in some cases longer if the woman is breastfeeding. If bleeding does occur during pregnancy, it is not normal and requires immediate attention from a health care provider.

Medication

Taking prescription or over-the-counter medication can also cause a menstrual period to occur later than normal. This happens mainly because many over-the-counter drugs can change the way the body produces the hormones estrogen and progesterone. Many medications can affect your menstrual cycle; these include anything from your standard aspirin to prescribed thyroid medication.

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