January 23, 2007 > Preventing Birth Defects
Preventing Birth Defects
Expectant mothers generally worry about the health of their unborn babies. Oftentimes, those worries are warranted. According to the Centers for Disease Control and Prevention (CDC), one of every 33 babies in the United States is born with a birth defect, ranging from minor to life-threatening.
While not all birth defects are preventable, many of them are. Educating parents about how they can increase their chances of having a healthy baby is the goal of National Birth Defects Prevention Month in January.
"A number of problems are caused by genetic abnormalities, such as sickle-cell anemia, Tay-Sachs disease and cystic fibrosis," says Dr. Elizabeth Kurkjian, a specialist in obstetrics and gynecology at Washington Hospital. "In these cases, a faulty or missing gene is the cause of the disorder, and it really can't be 'prevented.' However, parents who have a history of problems such as these in their families - or who already have an affected child - should discuss this with their doctor and consider being screened for genetic abnormalities before getting pregnant."
Dr. Kurkjian notes that some birth defects, such as Down syndrome, are due to chromosomal abnormalities, when a baby is born with too few or too many chromosomes, or a chromosome is damaged. "Down syndrome is one of a number of birth defects that are more common among older mothers," she says. "Studies show that a woman's risk of having a Down syndrome baby is one in 1,500 at age 20. By age 35, that risk has increased to one in 350. At age 40, the risk is one in 100. Older mothers also have a greater risk of high blood pressure and diabetes, which can complicate their pregnancies."
Another category of birth defects is that of "neural tube defects" such as spina bifida and brain anencephaly. Spina bifida happens when the spinal column doesn't close completely around the spinal cord. Anencephaly involves the lack of development of parts of the brain.
"Neural tube defects occur during the first few weeks of pregnancy, often before the mother realizes she is pregnant," Dr. Kurkjian explains. "Numerous studies have shown that these defects may be prevented if the mother gets enough folic acid, a B vitamin, prior to and during pregnancy. We encourage all women who are planning to become pregnant to make sure they get 400 micrograms of folic acid every day, either by taking a vitamin supplement containing folic acid or by eating breads and cereals that are enriched with the daily value of folic acid. A woman who has already had a baby with a neural tube defect should increase her intake of folic acid to 4 milligrams a day prior to becoming pregnant."
Once a woman is pregnant, there are screening tests available to detect problems such as Down syndrome and neural tube defects. Blood testing alone or in combination with ultrasound are the most common methods of screening. They are safe, simple and about 70% to 80% accurate. "Some women who are at higher risk may want to undergo amniocentesis to screen for birth defects," Dr. Kurkjian says. "This test entails taking a sample of the amniotic fluid surrounding the fetus in the uterus. The test is highly accurate for detecting many defects, but it can sometimes contribute to miscarriage."
Some birth defects are completely preventable, including fetal alcohol syndrome, which causes retarded growth and dysfunction of the central nervous system. "Avoiding alcohol, smoking and illegal drugs during pregnancy makes a huge difference in the health of your baby," Dr. Kurkjian stresses. "You also need to consult your doctor about any prescription or over-the-counter medications you are taking. Even mega-vitamin supplements can be harmful. For example, Vitamin A in large doses can cause birth defects. Expectant mothers also should limit their intake of fish such as tuna that can contain harmful levels of mercury. Eating a healthy diet and exercising regularly also will increase your chances of having a healthy baby."
Regular pre-natal visits to your doctor are essential during pregnancy, according to Dr. Kurkjian. "Ideally, women should consult their doctors before they try to become pregnant," she says. "Once you become pregnant, early and regular prenatal care is vital, both for you and your baby."
Tri-City Voice article re: birth defects