Infertility Causes, Ovulatory Disorders
The ovary contains approximately 400,000 eggs at birth and ovulates one each month. Ovarian disease can cause the lack of ovulation (anovulation), irregular ovulation, or reduction in egg quality. The ovaries are stimulated by a series of hormonal interactions. The hypothalamus, a small gland at the base of the brain, secretes gonadotropin-releasing hormone, which stimulates the pituitary gland to produce follicle stimulation hormone (FSH). FSH stimulates the development of the ovarian follicles, which contain the eggs, and luteinizing hormone (also produced by the pituitary) causes ovulation of the mature egg.
A breakdown in these hormonal events will prevent proper ovulation. Clomid is often used to treat ovulatory disorders. It works at the hypothalamus to stimulate production of gonadotropin releasing hormone, which stimulates the pituitary to release FSH. Higher levels of FSH (Gonal-F, Follistim, and Repronex) are achieved when it is administrated by injection.
Externally administered FSH is used in IVF cycles because it stimulates the development of more eggs than clomiphene, which are needed in ART procedures. FSH is also used in intrauterine insemination (IUI) especially when the cause of infertility is low natural levels of FSH as in hypogonadotropic hypogonadism known as Kallman’s syndrome. Hyperthyroidism can also cause anovulation as can polycystic ovarian disease.
FSH products (Gonal-F) should only be administered by a fertility specialist thoroughly trained in their use. Precise monitoring with blood estradiol tests and ultrasound is necessary to insure the appropriate dose, reduce the chance for side effects, and minimize the incidence of multiple births.
Another condition that can cause anovulation is hyperprolactinemia. This condition is caused by a tumor (usually benign) located at the base of the pituitary gland. Treatment with the drug Parlodel (bromocriptine) is often very effective in treating this condition.
Other conditions that can cause ovarian dysfunction include anorexia, stress, excessive exercise, age, some medications, radiation, or high dose chemotherapy. Additionally, some women are rarely born lacking one or both ovaries. If both ovaries are absent, donor egg IVF is the only hope of producing a genetically related child. Test for these conditions are discussed in the “Fertility Tests” section.
PCOS is a common cause of infertility and is present in up to 20% of infertile women. PCOS should be thought of as a “syndrome” and women who have PCOS typically exhibit a cluster of symptoms. Many of the characteristics are related to the over production of androgens, which are male hormones (testosterone) and include: increased facial hair, lowering of the voice, difficulty loosing weight, irregular or absent ovulation and irregular periods.
Most PCOS patients are insulin resistant meaning that they produce too much insulin to metabolize a given amount of carbohydrate. Insulin levels are chronically elevated which leads to the overproduction of androgens by the ovaries. These hormonal changes ultimately result in elevated androgens and the symptoms result in elevated androgens and the symptoms of PCOS. Elevated insulin levels can also produce long- term health consequences such as diabetes and cardiovascular disease.
Glucophage (Metformin) is an insulin- sensitizing drug that is now a first line treatment for most PCOS patients. Metformin does not induce ovulation; rather it normalizes insulin levels thus reducing androgen production and allowing normal ovulation to occur. Many specialists are opting to prescribe Metformin as long-term therapy to reduce the complications of PCOS, such as diabetes and cardiovascular disease. If Metformin alone is not successful, Clomid or FSH can be added to the treatment regimen to induce ovulation.
PCOS is difficult to manage and a reproductive endocrinologist should treat these patients, especially if ovulation induction drugs are used. PCOS patients often have an exaggerated response to FSH that can lead to very serious side effects including hyperstimulation and multiple pregnancy. Specialists are trained to manage these potential complications. Dr. Borkowski has extensive experience successfully treating PCOS patients.
Elevated levels of prolactin, in the absence of pregnancy, may indicate hypothyroidism or a tumor on the pituitary gland and cause irregular or absent ovulation. Prolactin is a hormone that stimulates milk production in the female and its level rises during pregnancy. The tumor is usually benign and can sometimes be removed via surgery or prolactin levels are lowered using medication (bromocriptine). Once the elevated levels are normalized, the chances of pregnancy are usually excellent.
Thyroid hormones are produced by the thyroid gland and levels are measured with blood tests. Hypothyroidism (low levels) can cause an increase in prolactin and negatively impact fertility. Hyperthyroidism can negatively affect the male’s sperm.