MedStar St. Mary's Hospital obstetrics offices offer non-invasive genetic screenings during pregnancy. If anything is abnormal, our patients are then referred to a high-risk OB for genetic counseling with whom we work closely.
Genetic counseling helps identify the risk of having a baby with birth defects, mental retardation, or an inherited disease. The process begins with a genetic counselor reviewing the parents' family, medical and obstetric histories. From this information, the counselor can determine and explain the possible genetic risks a couple may face in their pregnancy. Not every couple needs genetic counseling, but those with certain risk factors may find genetic counseling and testing helpful.
Risk factors include:
- Pregnancy at the age of 35 or older
- A history of multiple miscarriages
- A family history of a genetic disease
- A family history of mental retardation or birth defects
- Exposure to certain medications or drugs during pregnancy
- An ethnic or racial background in which a certain genetic disorder is more common (i.e. - sickle cell disease for African-Americans)
Once risks have been identified, a genetic counselor will discuss tests that are available to you and your baby. Certain blood tests may be offered to determine if parents are carriers for hereditary disorders. Other tests may be offered during the pregnancy to assess the baby for specific problems. These fetal diagnostic procedures may include:
- Amniocentesis: the sampling of amniotic fluid using a hollow needle inserted into the uterus, to screen for developmental abnormalities in a fetus
- Biophysical profiles: a prenatal test used to check on a baby's well-being using fetal heart rate monitoring (non-stress test) and fetal ultrasound
- Chorionic villus sampling: a prenatal test that involves taking a sample of some of the placental tissue to test for chromosomal abnormalities and some other genetic problems
- Detailed fetal ultrasound: an imaging technique that uses high-frequency sound waves to produce images of a baby in the uterus which can be used to evaluate possible problems or confirm a diagnosis
- Maternal serum screening (MSS): a blood test available to pregnant women to help determine the risk of Down syndrome, Edward syndrome or neural tube defects
- Ultrasound for Nuchal translucency: an ultrasound is used to measure a collection of fluid under the skin at the back of your baby's neck to determine whether or not a baby is likely to have Down's syndrome