The Link Between Hypothyroidism and Fertility
Why an Under-active Thyroid Can Impair Conception
Hypothyroidism is a condition that results from an under-active thyroid. The thyroid is a small organ of the endocrine system and is located on the neck, covering the trachea. The thyroid plays an important role in maintaining the body’s state of homeostasis (a state of metabolic equilibrium) by secreting hormones that govern physiological processes. Some of these include metabolism of carbohydrates and fat, body temperature, blood calcium levels, and protein synthesis.
A person who is suffering from hypothyroidism may experience depression, intolerance to cold temperatures, fatigue, constipation, and weight gain. For women, hypothyroidism can also impair fertility.
Complex biofeedback mechanisms dictate hormone production and secretion. The pituitary gland in the brain, often referred to as ‘the master gland’, serves as a relay center for modulating the activity of other endocrine glands. When the thyroid does not produce enough hormones to do its job effectively, the pituitary gland responds by trying to stimulate the thyroid even more; you can think of this as being analogous to a horse drawn buggy. When the horse slows down, the driver cracks a whip to stimulate the horse to move faster. In this case, the thyroid is the horse and the pituitary gland is the driver. But because the function of the thyroid is impaired, it fails to respond, just as a horse with a lame foot would.
The chronic yet ineffective increased stimulation of the thyroid by the pituitary results in changes in the levels of hormones that trigger the release of an egg from the ovary-namely leuteinizing hormone, or LH.
Since LH is required to trigger ovulation, the impairment of LH production by thyroid dysfunction results in infertility. Often times a woman who is infertile because of hypothyroidism experiences long or absent menstrual cycles. When she finally does experience a period, the bleeding is heavy due to excessive endometrial formation.
A simple blood test is all that is required to test for hypothyroidism. If you are experiencing any of the symptoms mentioned in this article you should consult your physician, as untreated thyroid dysfunction can lead to long term health problems, and in some cases death.