Conditions that affect the normal ovulation process resulting in failed or irregular ovulation are called ovulatory disorders. This also happens to be one of the most common causes of infertility in women. This is partly due to abnormal hormone levels like thyroid (thyroxine [T4] and triiodothyronine [T3]), insulin problems, pituitary gland disorders and other endocrine disorders in women.
Let’s start with the thyroid. The thyroid must be able to produce the needed amount hormones necessary for fetal and neonatal growth and development. There are many other major effects of abnormal thyroid levels but as it relates to infertility, they largely attribute to changes in ovulation and a woman’s period.
Ovulation can also be diminished by changes in the production of: sex hormone binding globulin (SHBG), follicle stimulating hormone (FSH), estrogen, and androgens just to name a few. The body compensates by fluctuating the production of thyroid releasing hormone (TRH) from the hypothalamus. These changes in TRH will ultimately affect the feedback loop between the hypothalamus, pituitary, and the ovary, leading to changes in a woman’s ovulation and menstruation. These changes can be very subtle, especially when symptoms of thyroid disorder are not obvious and do not lead to changes in periods or ovulation. Even before symptoms are able to present themselves they can lead to small changes in ovulation and endometrial receptivity, which then may have a profound effect on fertility.
Are there any symptoms?
The symptoms that a patient may experience differ for people who may have hypothyroidism and hyperthyroidism. Someone who has a hypothyroid may complain of: lethargy, mild weight gain, cold intolerance, constipation, dry skin, mental impairment, depression, irregular menses, and hoarseness. Physical symptoms noted by the physician on exam may include: an enlarged/tender thyroid gland, a low heart rate, changes in the texture of skin/hair, and changes in neurological reflexes. A person who has a hyperthyroid will complain of: nervousness, fast heart rate, heat intolerance, weight loss, emotional changes, and neck tenderness. Physical symptoms may include: an enlarged or nodular thyroid gland, bulging of the eyes (exophthalmos), rapid heart rate, tremors, changes in the skin and hair, and in severe cases loss of muscle tissue and cardiac changes noted on EKG.
A simple blood test to measure the thyroid stimulating hormone (TSH), is the most efficient and sensitive test for hypo or hyperthyroidism available. An elevated TSH value will indicate thyroid failure and a lack of adequate amounts of thyroid hormone to maintain normal body functioning. On the other hand, a low TSH value indicates excess production of thyroid hormone.
For those who are super sluethers by keeping tabs on their numbers, the normal range of serum TSH is 0.5 – 5.0 mU/ml. If the TSH value is abnormal, then an estimate of T4 becomes necessary to further evaluate the exact location of the source of the hormone problem (i.e.: the thyroid, the pituitary, or hypothalamus).
Because hyperthyroidism and hypothyroidism are like night and day, the treatments are also different based on the type of thyroid disorder. Someone with hypothyroidism will require thyroid replacement therapy to supply the thyroid hormone that the body is not able to produce.
For someone with hyperthyroidism, treatment is based on decreasing production of thyroid hormones. In most instances, medications are administered to inhibit both thyroid gland production and secretion of T3 and T4. Some people may even temporarily require other medications to counteract the effects of excess thyroid hormone throughout the body until such time as the quantities of thyroid hormone have been reduced. Once the source of increased thyroid hormone production is found, treatment with radioactive iodine will be used to destroy the site of overproduction.