Does Thyroid Affect Periods?

The thyroid gland in the neck, an essential endocrine organ, controls metabolic activities by releasing the hormones triiodothyronine (T3) and thyroxine (T4). These hormones interdependently regulate reproductive processes, menstrual irregularities, and hormonal rates.

Thyroid disorders may make the menstrual cycle irregular or change the pattern of bleeding experienced by the women. This article evaluates the complex relationship between thyroid health and menstruation, including their symptoms, diagnosis, and management, to provide a deeper understanding of their crucial connection.

The Link Between Thyroid Function and Menstrual Health

Thyroid hormones are essential modulators of the menstrual cycle via a complex Hypothalamic-Pituitary-Gonadal (HPG) axis on the ovaries. These hormones affect reproductive function, influencing the release of Follicle-Stimulating Hormone (FSH) and Luteinising Hormone (LH), which are necessary for ovulation.

However, when there is a disorder in the thyroid, such as hyperthyroidism and hypothyroidism, the gland distorts the intricate balance of hormones. Hypothyroidism lowers T3 (triiodothyronine) and T4 (thyroxine) levels, which increases the production of prolactin hormone.

Prolactin is known to inhibit ovulation, another reason why women can experience irregular menstrual periods. On the other hand, hyperthyroidism increases metabolism, causing changes in hormonal balance and disruption of menstrual cycles. These variations directly influence the ovaries' ability to produce adequate estrogen for menstrual cycle regulation.

Common Menstrual Irregularities Associated with Thyroid Disorders

Oligomenorrhea or infrequent menstrual cycles are common in cases of hypothyroidism, while polyamenorrhea, meaning frequent cycles, indicates hyperthyroid pathology. Hypermenorrhea, excessive menstrual bleeding, is seen mainly in hypothyroid states.

The most definitive signal is amenorrhea, a condition where the menstrual cycle is absent at all. Though it rarely occurs, inflammation may take place in both hyper and hypothyroid states if the hormonal shift is severe. The last significant effect of thyroid dysfunction is anovulation, which implies failure of ovulation and leads to fertility problems.

Types of Thyroid Disorders Affecting Menstrual Cycles

Thyroid disorders are one of the lesser-known aspects of gynaecological health and infertility, which might have a significant impact on women’s menstrual cycles. Knowing how hypothyroidism or hyperthyroidism, two thyroid disorders, can affect a woman’s menstrual cycle is essential for effective management of women’s health.

Hypothyroidism and its Impact on Periods

• Reduced levels of thyroid hormones result in persistent and abundant menstrual flow.
• Irregular or infrequent menstrual cycles (oligomenorrhea).
• Increased risk of anovulation impacting the chances of conceiving.
• High levels of prolactin complicate the hormonal balance.
• Predisposition to the development of ovarian cysts.
• Possibility of an increase in the cycle duration.

Hyperthyroidism and Menstrual Disturbances

• Frequent periods or shorter time spans between two consecutive periods (polymenorrhea).
• Reduced and less frequent menstrual flow.
• Early menopause due to changes in hormonal regulation.
• Increased likelihood of spotting between periods.
• Reduced total menstrual flow.
• Higher risk of premature ovarian insufficiency.

Symptoms Indicating Thyroid-Related Menstrual Issues

Thyroid-associated menstrual changes are a range of bodily signs and symptoms indicative of endocrinological dysfunction. Thyroid dysfunction may exhibit significant alterations in the menstrual pattern, such as irregular bleeding or the complete absence of periods for several months, a condition called amenorrhea.

Other symptoms include unanticipated weight gain or loss, persistent fatigue, muscle and joint pain, and changes in metabolism. These problems are usually accompanied by depression, skin dryness, changes in hair texture and constipation.

Recognising Menstrual Cycle Changes

Menstrual irregularities play significant roles in informing probable thyroid problems. Hypoactive thyroid function can lead to the development of lengthy or abundant menstrual flow, as well as the absence or irregularity of the menstrual cycle.

It may also influence peri-pubertal development. Some women may develop an early onset of menstruation or delayed menstruation or may experience menopause before forty years of age. 

Diagnosis of Thyroid Disorders and Menstrual Irregularities

Diagnosis of thyroid-related menstrual problems should involve both endocrinological and gynaecological evaluations.

Thyroid Function Tests

Thyroid function tests are beneficial for identifying hormonal dysfunction. In other cases, the basic diagnostic exam entails TSH (Thyroid-Stimulating Hormone), T4, and T3 hormone tests. Values above the normal range are diagnostic of hypothyroidism, and values below the normal range are diagnostic of hyperthyroidism.

Gynaecological Evaluation

Gynaecological assessment systematically analyses menstrual history, cycles, and symptoms. An internal examination includes pelvic ultrasounds or a physical examination to determine if there are likely to be any structural problems or reproductive health concerns. Tracking of ovulation yields further information concerning hormonal fluctuations.

Treatment and Management of Thyroid Disorders and Menstrual Irregularities

A combination of pharmacological therapies and lifestyle changes are required in women who experience thyroid dysfunction and menstrual health issues. The purpose is to regain reproductive hormone homeostasis, regulate menstrual cycles, and enhance fertility.

• Levothyroxine (Synthroid): A synthetic form of the hormone used to help treat hypothyroidism to supplement the missing thyroid hormones.
• Antithyroid Drugs (Methimazole, Propylthiouracil): Drugs that help to reduce the levels of hormones in hyperthyroidism.

These drugs are used to normalise thyroid function and relieve symptoms associated with it. Levothyroxine helps restore normal TSH, while antithyroid medication lowers the thyroid gland's output.

Advanced Interventions

• Radioactive Iodine Therapy: A process that eliminates thyroid tissue in managing hyperthyroidism.
• Thyroid Surgery (Thyroidectomy): It involves excision of the thyroid lobe or all thyroid gland, which is common in cancerous diseases, large thyroidopathies, or large nodules.

Lifestyle Modifications and Their Effect on Menstrual Health

Consumption of a balanced diet helps regulate the menstrual cycle. Daily physical activities, such as practising yoga and meditating, help regulate hormones. Stress management also helps thyroid control and regular menstruation.

Proper sleep hygiene helps balance hormones and regulate menstrual cycles. Limiting caffeine and alcohol consumption also helps prevent fluctuations in hormone levels.

Long-term Complications if Thyroid Disorders are Left Untreated

Unaddressed thyroid conditions can lead to numerous secondary effects on key aspects of overall health, including fertility issues and other systemic health concerns. If left untreated, thyroid disorders can significantly affect reproductive health in the following ways:

• Hypothyroidism leads to problems of dysmenorrhoea, oligomenorrhoea and anaemia, infertility due to difficult ovulation, and threatened abortions, among others.
• Hyperthyroidism may increase the risk of adverse birth outcomes, including preterm birth and low birth weight and is associated with an increased risk of miscarriage.

Other Health Risks Related to Untreated Thyroid Disorders

Hypothyroidism can raise cholesterol levels and reduce cardiac output, leading to heart problems, while hyperthyroidism may cause arrhythmias, tachycardia, and even heart failure. Both conditions can also result in anxiety, depression, and mood swings that deeply affect mental well-being.

Fatigue and weakness are common with hypothyroidism, making daily tasks difficult. It can also cause weight gain due to a slower metabolism, while hyperthyroidism often leads to weight loss and weakness. Additionally, hypothyroidism can lead to dry skin, hair loss, brittle nails, and memory issues like brain fog.

When to Consult a Healthcare Provider?

Changes in the menstrual cycle, such as prolonged or heavy periods or the need to change pads or tampons frequently, may indicate thyroid irregularities. Other signs include irregular cycle lengths or periods occurring after long intervals.

Any change in menstrual flow, whether heavier or lighter, should be taken seriously. Difficulty with conception, especially alongside irregular cycles, may point to thyroid-related infertility. Thyroid function tests and early evaluation can help with diagnosis and treatment.

Conclusion

Thyroid disorders can severely impact menstrual health, making timely professional care essential. Recognising common symptoms, seeking early diagnosis, and using effective management strategies are key to addressing thyroid-related menstrual issues and maintaining hormonal balance. Early intervention is crucial for protecting reproductive health.