The menstrual cycle is the monthly series of changes the female body goes through to prepare for pregnancy. Each month, one of the ovaries releases an egg (this process is called ovulation). Some hormonal changes occur at this time to get the uterus ready for pregnancy. But if the released egg isn’t fertilized during ovulation, the lining of the uterus sheds through the vagina resulting in the menstrual period. In adult women, the menstrual cycle lasts from 21 to 40 days, with the average being 28 days. The cycle recurs until menopause, about age 50, at which time ovarian function ceases and brings the woman’s reproductive life to an end.
The menstrual cycle is counted from the first day of one period to the first day of the next period. The cycle isn’t the same but unique to each woman. Menstrual bleeding might happen every 21 to 35 days and last 2 to 7 days. For the first few years after menstruation begins, long cycles are common but tend to shorten and become more regular as people age.
The menstrual cycle might be regular i.e. about the same length every month or somewhat irregular. The period might be light or heavy, painful or pain-free, long or short.
Certain kinds of birth control, such as extended-cycle birth control pills and intrauterine devices (IUDs), will change a menstrual cycle. When you get close to the time when your menstrual cycles will end, called menopause, your cycle might become irregular again. However, the risk of cancer of the uterus gets higher as you age, hence it is important to talk with your health care provider about any irregular bleeding around menopause.
Menstrual cycle irregularities may occur for different reasons, including:
- Pregnancy or breast-feeding.A missed period can be an early symptom of pregnancy. Breast-feeding typically delays the return of the period after pregnancy.
- Eating disorders, extreme weight loss or too much exercising.Eating disorders such as anorexia nervosa, extreme weight loss and higher physical activity can interrupt the period.
- Polycystic ovary syndrome (PCOS).People with this common disorder may have irregular periods. They also can have enlarged ovaries that contain small collections of fluid — called follicles — located in each ovary. These follicles can be seen during an ultrasound exam. People who have PCOS often have more follicles in the ovaries than other people.
- Premature ovarian failure.Premature ovarian failure refers to the loss of typical ovarian function before age 40. People who have this condition, also known as primary ovarian insufficiency, might have irregular or occasional periods for years.
- Pelvic inflammatory disease (PID).This infection of the reproductive organs can cause irregular menstrual bleeding.
- Uterine fibroids.Uterine fibroids are growths in the uterus that are not cancer. They can cause heavy and prolonged menstrual periods.
How to calculate the menstrual cycle
Calculating the menstrual cycle involves tracking the start and end dates of the periods over several months. To get started:
- Keep a menstrual calendar: Begin by recording the first day of your period each month. This will help establish a pattern and identify the length of your cycle.
- Determine the Length of Your Cycle: Count the number of days from the first day of your period to the day before your next period begins. Repeat this process for at least three consecutive months to determine the average length of your cycle.
- Identify the Ovulation Phase: Ovulation usually occurs around the middle of the menstrual cycle, typically 14 days before the next period. You can use this to estimate the fertile window and increase or decrease the chances of conception.
If you want to track more than the basics, a period tracking app can help. These handy tools are easily accessible on your smartphone and make logging data and symptoms quick and easy. However, period tracking apps may not be 100% accurate. Any information they give you about your cycle and predicted fertility windows is just an estimate.
Importance of knowing how to calculate your menstrual cycle
- Reproductive Health: Understanding your menstrual cycle enables you to recognize irregularities or abnormalities that may indicate underlying health issues. It allows you to identify irregular cycles, excessively heavy or light bleeding, or the absence of period altogether, which could be indicative of hormonal imbalances, polycystic ovary syndrome (PCOS), or other reproductive disorders. Timely detection and management of these conditions can help maintain fertility and overall well-being.
- Family Planning: Knowledge of your menstrual cycle is crucial for family planning, whether you’re trying to conceive or aiming to avoid pregnancy. By identifying your fertile days, you can plan intercourse accordingly, maximizing your chances of conception or utilizing contraceptive methods effectively.
- Managing Menstrual Symptoms: Tracking your cycle allows you to anticipate and manage menstrual symptoms better. By identifying the premenstrual phase, you can prepare for potential mood swings, bloating, or discomfort. This awareness helps you prioritize self-care activities, such as exercise, a healthy diet, and stress reduction techniques, to alleviate discomfort and improve your overall well-being.
Consequences of not knowing how to calculate your menstrual cycle:
- Unplanned Pregnancies: Without awareness of your fertile window, there is an increased risk of unplanned pregnancies. This can lead to emotional and financial stress, as well as impact life choices and career plans.
- Delayed Diagnosis of Reproductive Disorders: Irregular or absent menstrual cycles may indicate underlying reproductive disorders that require medical attention. Failing to recognize these signs due to a lack of understanding can result in delayed diagnosis and potential complications.
- Emotional and Physical Discomfort: Menstrual symptoms can be overwhelming, affecting both your emotional and physical well-being. Without knowledge of your cycle, it becomes challenging to predict and manage these symptoms effectively, leading to unnecessary discomfort and stress.
Knowing your menstrual cycle is crucial for women to maintain reproductive health, plan pregnancies effectively, and manage menstrual symptoms. By understanding how to calculate your menstrual cycle and tracking it consistently, you empower yourself with valuable information that enables informed decisions regarding family planning, seeking medical care, and self-care. It also empowers you to take charge of your reproductive health and overall well-being, fostering a healthier and more fulfilling life.
References
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- Hillard PJ. Menstruation in adolescents: what do we know? And what do we do with the information?. J Pediatr Adolesc Gynecol. 2014
- Menstruation – Normal menstruation | Britannica
- Menstrual cycle: What’s normal, what’s not – Mayo Clinic
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- The Importance Of Understanding Your Menstrual Cycle – GirlTalkHQ