The Thyroid Factor
The Effects Of A Dysfunctional Thyroid
Undiagnosed and untreated thyroid disease is a cause of infertility in women. Hyper- or hypo-thyroidism both have a profound effect upon whether woman can become and stay pregnant. The malfunctioning of the thyroid gland can alter the balance of reproductive hormones in a woman's body and stop ovulation. However, by keeping thyroid levels under control through medication, having regular professional care, and taking proper care of herself, a woman can experience a successful outcome to her pregnancy desires.
The way thyroid disease can affect fertility is through causing anovulation-meaning no egg is released from the ovaries. Without an egg to be fertilized, conception is a moot point. A malfunctioning thyroid upsets the natural reproductive hormone balance in the body and, even though a woman may be having a regular menstrual period, she may not be ovulating. Sadly, that fact often goes unnoticed for a long time.
Ovulation Is Affected
The pituitary gland produces luteinizing hormone (LH) which stimulates the release of an egg from an ovary, making it available for fertilization. If there is either a deficiency or over abundance of thyroid hormone, it may affect the LH and there may not be ovulation. The best way to tell if ovulation is happening is to test the LH levels. The test is easy to accomplish with an ovulation predictor kit, which identifies the LH surge that triggers ovulation.
Luteal phase defect, or a shortened luteal phase, is another result of thyroid malfunction. This problem can cause an inability in the uterus to hold a fertilized egg. Because the luteal phase is not long enough, endometrial tissue production is limited and so there is not enough lining in the uterus to sustain a pregnancy.
Overproduction Prolactin = Infertility
When the thyroid is not actively functioning (hypothyroidism), there can be an increase of the hormone called prolactin. Prolactin is produced by the pituitary gland and is important to the production of breast milk in post-partum women. Excessive amounts of prolactin may prevent ovulation or cause irregular or absent menstrual cycles. The culprit in these cases is the hormone thyrotropin releasing hormone (TRH), which is produced by the hypothalamus. Hypothyroidism is also complicit in another cause of infertility, PCOS.
The Thyroid Stimulating Hormone Test
In order to determine whether the thyroid is creating the fertility problem, the TSH (thyroid stimulating hormone) levels are key. A TSH test indicates where the levels are in the body. Many labs believe that levels of .5 to 5.5 TSH are fine; however, many endocrinologists prefer to have levels much lower at .3 to 3.0. Frequently a woman with a thyroid disorder is unable to conceive or carry a pregnancy unless her TSH levels are as low as 1.0 to 2.0.
It is very important that a well-trained and experienced endocrinologist with extensive background in thyroid-related infertility be involved in the diagnosis and treatment of women suffering with thyroid dysfunction. With proper diagnosis, treatment, and maintenance a woman can experience the joy of pregnancy and birth.