Is This the Reason Your Period is Irregular?

No matter when you joined the period club, you know the joys of tender breasts, sleep disturbance, weird bowel movements, inconvenient acne, and all of the feels. Theoretically, it happens every month—right?

Well, maybe not.

Menstruation is often overlooked as a tool to tell us about the state of our health. Super long cycles, light or heavy bleeding, skipped periods, or strange colors can give us useful information about our overall health.

A regular menstrual cycle

What is regular can vary amongst women. Regardless, it’s helpful to know what a regular menstrual cycle looks like for most women: 

  • A regular period cycle lasts 26-32 days. Wherever your timeline falls, the goal is consistency each month.
  • One period symptom may be a slight heaviness in your lower abdomen. If your cramping requires hot water bottles or medication, you should speak to your doctor.
  • The color of blood should be bright red to cranberry color. You shouldn’t experience heavy clotting. 
  • Bleeding should last anywhere from 4-7 days. As you get older, the amount of bleeding you experience should lessen.

If your cycle isn’t as described above, it’s worth digging in to figure out what’s going on with Auntie Flo.  

Here are some possible causes for an irregular period:

  • Stress can affect the hypothalamus — the part of your brain responsible for regulating your period
  • Birth control can disrupt or disappear your natural cycle 
  • Perimenopause can cause a collection of period-related symptoms that mimic menopause before the body fully commits 
  • Polycystic ovarian syndrome, hyperthyroidism, or hypothyroidism can cause hormonal imbalances

In this article, we want to focus specifically on how hypothyroidism affects your period and how to work toward a healthier menstrual cycle. 

What is hypothyroidism?

Hypothyroidism is a condition in which the thyroid gland is not able to produce enough thyroid hormone. The thyroid is a butterfly-shaped gland at the base of your neck. As part of the endocrine system, the thyroid gland makes and stores hormones that help regulate your body’s metabolism in the form of blood pressure, blood temperature, and heart rate. When your thyroid hormone production drops, your body processes slow down and change. This condition affects virtually every system in your body.

Common symptoms of hypothyroidism include: 

  • Fatigue
  • Increased sensitivity to cold
  • Dry, scaly skin
  • Weight gain or increased difficulty losing weight
  • Muscle aches, tenderness, and stiffness
  • Heavier than normal or irregular menstrual periods
  • Thinning hair or hair loss
  • Feelings of depression
  • Impaired memory or brain fog
  • Enlarged thyroid gland (goiter)

Thyroid function has much to do with your reproductive system. An imbalance of thyroid hormones can cause heavy menstrual periods (menorrhagia), infrequent menstrual periods (oligomenorrhoea), or absent menstrual periods (amenorrhea).

How an underactive thyroid can cause irregular periods

Heavy, irregular, or absent menstrual periods are likely all connected to metabolic disturbances in the carefully regulated system between the hypothalamus, pituitary gland, and ovaries. This system controls female reproduction. When one spoke of the wheel is out of balance, it can cause the whole system to go off course.

Often we think of metabolism as being explicitly related to our diet or weight. And while this isn’t incorrect, metabolism is the set of chemical reactions happening in all of our cells, all the time. When your thyroid hormone production drops, your body’s metabolism slows.

An increase in prolactin

Hypothyroidism causes an increase in the levels of thyroid-releasing hormone (TRH), which in turn stimulates the release of thyroid-stimulating hormone (TSH) and prolactin. Prolactin is a hormone produced by the pituitary gland. Often referred to as the “milk hormone,” its job is to support ovulation, reproduction, immunity, blood cell formation, and above all, stimulate breast milk production.

Too much prolactin can interfere with the normal production of other hormones like estrogen and progesterone. This interference can change or stop ovulation and can lead to irregular or skipped periods. 

Bleeding without ovulating

Hypothyroidism may cause anovulatory bleeding. 

You assume that your period is a sign that you’re ovulating, but this isn’t always the case. What is meant to happen during ovulation is for the ovary to release an egg. However, sometimes the body skips ovulation, in spite of monthly bleeding. This is known as anovulation. 

Usually, the release of an egg stimulates the production of progesterone, which helps to regulate the menstrual cycle. If the egg doesn’t release, then there is an insufficient level of progesterone, meaning that estrogen begins to circulate unopposed.

Estrogen controls the growth of the uterine lining during the first part of the cycle. Without progesterone to keep it in check, unopposed estrogen can lead to excessive growth of the uterine lining. This excessive production may cause heavy bleeding. 

Treat hypothyroidism to regulate your period

If you experience menstrual irregularity, speak to your doctor about taking a blood test to understand how your thyroid is functioning. Many labs only look at thyroid-stimulating hormone (TSH), but it’s critical to also measure fT3, fT4, and TPO antibodies to understand the full picture.

Should your results show that your thyroid is underactive, it is easily treatable in almost everyone. Optimizing your thyroid levels with medication is usually the first step in minimizing symptoms like menstrual changes. When choosing thyroid medication with your doctor, remember that there is no one-size-fits-all treatment. 

Beyond taking thyroid hormone, you can support your thyroid with nutrition and lifestyle modifications. Talk to a doctor who can assess your symptoms, history, and lab results to determine the best treatment plan for you.

January is National Thyroid Awareness Month

In December 2019, Paloma Health conducted a survey of 232 thyroid patients to better understand the current state of thyroid care in the United States. Sixty-eight percent of participants say they waited over a year with symptoms for diagnosis. Over half of those people waited over three years!

If you’ve experienced frustrating period symptoms, you know that this is unacceptable. 

For each at-home thyroid blood test kit purchased on Paloma Health’s website during Thyroid Awareness Month in January, Paloma will gift a free test kit to a friend of your choosing. 

Get your #ThyroidChecked to learn if it may be to blame for your irregular period.

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