Blood Tests for Men
For most infertile men, the semen analysis is the only test which needs to be done – after all, the only job of a man is to provide sperm to fertilise the egg ! For men with a low sperm count, there is no need to do any other tests, since these do not provide any useful information. However, many doctors still do blood tests for measuring the levels of key reproductive hormones, such as prolactin, FSH, LH and testosterone. These are just a waste of time
and money since they provide no useful information and do not alter the treatment plan.
For men with azoospermia ( zero sperm count), additional blood tests may be useful . The serum FSH (follicle-stimulating hormone) level test is a useful one for assessing testicular function. If the reason for the azoospermia is testicular failure, then this is reflected in a raised FSH level. This is because, in these patients, the testis also fails to produce a hormone called inhibin (which normally suppresses FSH levels to their normal range). A high FSH level is usually diagnostic of primary testicular failure, a condition in which the seminiferous tubules in the testes do not produce sperm normally, because they are damaged.
This test is done by a radioimmunoassay or chemiluminescent assay, and since it is a sophisticated test, it is best done in a specialized laboratory. Abnormal test results should be repeated and rechecked for confirmation. The other reason for a high FSH level in some men is the consumption of clomiphene (a medicine often prescribed for the empiric treatment of oligospermia). This is why the test should be done only when no medication is being taken. While a high FSH level is diagnostic of testicular failure, a normal FSH level provides no useful information. Thus, men with complete testicular failure may also have normal FSH levels.
While a high FSH level suggests primary testicular failure, it cannot differentiate between partial testicular failure and complete testicular failure. This means that even men with very high FSH levels can have occasional areas of sperm production in their testes, and these testicular sperm can be used for TESA-ICSI ( testicular sperm aspiration and intracytoplasmic sperm injection) treatment.
Rarely, the FSH level may be low. A low FSH level is found in patients with hypogonadotropic hypogonadism. Hypogonadotropic hypogonadism is an uncommon (but treatable!) cause of azoospermia. Along with an FSH level test, most doctors also do a LH (luteinizing hormone) level test, which provides mostly the same information.
A testosterone level test provides information on whether or not the testes are producing adequate amounts of the male hormone, namely, testosterone. Most infertile men have normal testosterone levels, because the compartment for testosterone production is separate from the compartment which produces sperm, and is usually intact in infertile men. A low testosterone level causes a decreased libido and this can be treated by testosterone replacement therapy in the form of tablets or injections. Of course, this therapy will not increase the sperm count.
Types of Infertility Blood Tests
There are various blood tests conducted for both men and women to test infertility causes.
1. Luteinizing Hormone (LH) and Progesterone Tests
This infertility blood test determines if the women is ovulating. In the males, the LH test can help discover if he has a pituitary gland problem.
In females, the Lutenizing Hormone helps regulate the menstrual cycle and egg production (ovulation).
• FSH testing
Sometimes women have irregular supply of egg in the ovaries. The follicle-stimulating hormone (FSH) test is conducted to determine the condition of a woman’s egg supply (ovarian reserve). The FSH test helps control a womans menstrual cycle and also the egg production. The FSH is also produced by the pituitary gland. In males with a low sperm count, the FSH test is used to find the source of the problem. Very high or Very low FSH levels may indicate that the egg or sperm count is very low or may not be produced at all.
• Testosterone Test
This test is conducted for males. This test determines if the pituitary gland or the testicles are causing infertility in the male. Low testosterone may indicate low sperm count leading to infertility.
• Antibody Blood Tests for Infertility
Sometimes there are antisperm antibodies in the blood, semen and vaginal fluids. Antibody infertility blood tests are conducted to detect these antibodies. These antibodies damage or kill the sperm. It becomes very difficult for the sperm to fertilize an egg in such cases. The antibodies look for special proteins in the blood to attack the sperm, semen and in the vaginal fluids.