Ovulatory Disorders Caused by Thyroid Dysfunction

Many organs from all areas of the human body rely upon thyroid hormone to function as they should. Thyroxine (T4) and triiodothyronine (T3), both thyroid hormones, are critical for normal development of the fetus and neonate. These hormones also ensure adult organs and their systems function properly. This includes the following parts of the body:

  • Skeleton
  • Cardiovascular system
  • Metabolism of lipids and carbohydrates
  • Neuromuscular system

Ovulation, menstruation and other processes are largely affected by abnormal production of thyroid hormones. Impaired ovulation can result from altered levels of the following hormones:

  • Estrogen
  • Sex hormone binding globulin (SHBG)
  • Androgens
  • Follicle stimulating hormone (FSH)
  • Other hormones

To compensate for these impairments, the body changes its hypothalamus production of thyroid releasing hormone. In turn, these thyroid releasing hormone alterations affect the pituitary gland, hypothalamus and ovaries. The result is alteration of ovulation and menstruation.

Changes in ovulation and menstruation may be subtle. This is particularly true when symptoms of the dysfunctional thyroid are not markedly present and do not cause changes in ovulation or menses. There may be profound effects on fertility even before symptoms manifest, however. This happens in the early stages of thyroid dysfunction, which can cause undetected changes in endometrial receptivity and ovulation.


Diagnosis of Thyroid Dysfunction Causing Ovulatory Disorders

Diagnosis and treatment of thyroid disorders are important for diagnosis of associated ovulatory disorders. Symptoms of hypothyroidism and hyperthyroidism differ, as do patient complaints as part of each type of thyroid dysfunction.

A hypothyroid patient may experience the following symptoms:

  • Lethargy
  • Mild weight gain
  • Cold intolerance
  • Dry skin
  • Constipation
  • Depression
  • Hoarseness
  • Mental impairment
  • Irregular menses

A physical exam by a doctor may provide the following findings of hypothyroidism:

  • Enlarged and/or tender thyroid gland
  • Changes in texture of skin and hair
  • Low heart rate
  • Changes in neurological reflexes

Hyperthyroid patients will often complain of the following symptoms:

  • Fast heart rate
  • Sleeplessness
  • Emotional changes
  • Neck tenderness
  • Weight loss
  • Heat intolerance
  • Nervousness

Physical findings of a doctor’s examination may include:

  • Nodules or enlargement of the thyroid gland
  • Exophthalmos, bulging of the eyes
  • Rapid heart rate
  • Changes in hair and skin
  • Tremors
  • Loss of muscle tissue
  • EKG-notable cardiac changes

Measurement of thyroid stimulating hormone (TSH) through a blood test is the most effective means of determination of a diagnosis of hypothyroidism or hyperthyroidism. TSH value elevation presented by hypothyroidism indicates thyroid failure. In these patients, not enough thyroid hormone exists to maintain normal functioning of the body. When low TSH is presented by the blood test, this means that excess thyroid hormone is being produced.

Serum TSH ranges of 0.5 to 5.0 mU/ml are normal. Abnormal TSH values must lead to evaluation of the serum free-T4. This will help determine the precise location of the thyroid’s dysfunction. The dysfunction can be at the thyroid, hypothalamus or pituitary.


Treatment of Thyroid Dysfunction

The type of thyroid dysfunction will determine best treatment. Hypothyroid patients are prescribed thyroid replacement therapy. This replaces the body’s deficient thyroid hormone.

Hyperthyroidism treatment works to decrease production of thyroid hormones. To accomplish this, medications are prescribed to inhibit the thyroid’s production and secretion of T3 and T4. Other medications may be temporarily needed by some patients to resolve effects of excess thyroid hormone in the body. When thyroid hormones are successfully reduced through prescribed therapies, these supplemental medications can be eliminated. The primary treatment for overproduction of thyroid hormone is use of radioactive iodine to destroy the problem area.