For about 10 percent of all infertile couples, the cause of the infertility cannot be readily determined by conventional diagnostic procedures. Such cases are referred to as "unexplained infertility."
Modern IVF technology is making great strides in helping to identify some of the causes of so-called unexplained infertility. Improved testing techniques have made infertility easier to diagnose, and the majority of cases can now be diagnosed and generally are treatable.
Recent research has demonstrated that many women with unexplained infertility ultimately are found to have pelvic endometriosis that cannot yet be detected by direct vision during laparoscopy or surgery. For example, a condition called nonpigmented endometriosis, in which the endometrium may be growing inside the pelvic cavity with many of the same deleterious effects as overt endometriosis, cannot be detected by direct vision because no visible bleeding has occurred in these lesions. The fertility of these patients may be every bit as much compromised by these conditions as if they had detectable endometriosis.
Sometimes infertility is due to nonreceptivity of the uterine lining (endometrium) to the embryo (fertilized and divided egg). This can be due be the lining being too thin to accommodate the implanting root system of the embryo, scarring of the lining, infection or immunologic factors. The latter is fast becoming an important consideration, especially in cases of unexplained failure following the use of fertility drugs (with or without "artificial" insemination or IVF).
Dr. Geoffrey Sher is founder of Sher Institutes of Reproductive Medicine and has long been considered a pioneer in the science and business of reproductive medicine. He has assisted more than 25,000 women in the births of their babies after treating their infertility.
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