Should we see a genetic counselor?
Modern genetics has identified 3,000 different birth defects that can occur in one in 29 births. Yet the risk of an individual couple having a child with an abnormality depends on a variety of factors. Birth defects result from genes alone or from environmental causes such as drug or alcohol abuse, infections, or exposure to medications or chemicals. Some result from a combination of heredity and environment. Certain diseases, like cystic fibrosis, are transmitted by a parent who is a "carrier", which means that the parent doesn't have the disease but carries a recessive gene that the child inherits. Some birth defects can be fatal, while others present lifelong challenges.
Genetic counseling provides information about human genetics based on family history and various tests. Ideally, couples may want to discuss genetic counseling before they conceive. In pre-conception counseling, a genetic counselor looks at the couple's state of health, the woman's age, whether she has diabetes or a seizure disorder, family history, and ethnicity. The counselor will also recommend that the woman begin taking vitamins containing folic acid three months prior to conception in order to prevent birth defects. Genetic counseling is often advised for women older than 35 because chances of having a child with Down Syndrome increase with maternal age. If a woman has diabetes or a seizure disorder, she should discuss medications with her doctor before becoming pregnant. Family history and ethnicity are important reasons to consider genetic counseling because some disorders occur more often in particular groups (e.g. Tay-Sachs in Jewish Europeans, thalassemia in Asians and Mediterraneans, sickle cell anemia in African Americans, and cystic fibrosis in Caucasians). Obtaining a family medical history enables care providers to consider the health of parents, their parents and grandparents. Once she is pregnant, a woman is offered a "triple screen" test that can pick up abnormalities. This blood test is done between 14 and 22 weeks, and results are usually back in a week. This test "risk-sorts;" that is, it doesn't make a diagnosis but only suggests possibilities that require further testing — usually by ultrasound or amniocentesis.
Ultrasound is a non-invasive technique using sound waves to show an image of the uterus and fetus. It can measure, for example, thickness of the fetus's neck, which may indicate read more
