tion to seek testing. The committee believes that clients should be encouraged to inform relatives about pertinent genetic information, but that only rare circumstances would warrant disclosure of genetic information without the consent of the client (see Chapter 8),

Prenatal Diagnosis

Some of the most difficult issues today in genetic diagnosis, testing, and screening surround prenatal diagnosis. The ability to diagnose genetic disorders far exceeds any ability to treat or cure them, and this situation is likely to prevail for a substantial period into the future. Since few diagnosable disorders are now treatable or preventable, few options yet exist for the use of genetics knowledge. Reproductive planning and decision making constitute one of the principal uses of such genetic knowledge, including evaluation of reproductive risk, decisions about whether to selectively abort fetuses identified as affected or highly likely to be affected by diagnosable genetic disorders, or preparing for the birth of an affected child. To compound the difficulties and uncertainties of such decision making, many of the genetic disorders that can now be diagnosed are highly variable in their expressivity, yet information about severity is rarely available through prenatal diagnosis. Prenatal diagnostic decisions are among the most personal in anyone's life and involve difficult psychological, ethical, legal, and social issues for anyone faced with them.

Some prenatal tests are screening tests (e.g., maternal serum alpha-fetoprotein), and other techniques permit diagnosis of certain genetic disorders. Again, the education and counseling needs will differ depending on the nature of the disorder for which the test is being done and the indication for the procedure. The majority of prenatal diagnoses are conducted for advanced maternal age, which increases the risk of a chromosomal abnormality, such as Down syndrome, in the fetus. In general, prenatal diagnosis for advanced maternal age is considered a genetic screening procedure because, although the risk of a chromosomal abnormality increases with age, it does so uniformly across the population (i.e., women of the same age carry the same risk). The majority of obstetrician-gynecologists now routinely offer prenatal diagnosis to women aged 35 and older. These physicians could conduct pretest education and counseling, and/or nurses appropriately trained in prenatal genetics could also provide pretest education and counseling. In the event a fetus is identified to have or be at high risk for a genetic disorder, however, posttest counseling should be conducted by a trained genetics professional in collaboration with the primary care physician.

The educational component of prenatal diagnosis includes information about the testing procedure, as well as the risks of the procedure for both mother and fetus in relation to the chances of detecting an abnormality. All of the options available when an abnormality is detected should then be discussed with the client, including the option of terminating the pregnancy. Psychosocial counseling



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