Why is Prenatal Diagnosis Important?
Pregnant women who undergo prenatal diagnosis do so for several reasons. As mentioned, a major purpose of the diagnosing process is to assess for congenital anomalies, which account for 20 to 25% of perinatal deaths. A pregnant women may come to our office to undergo prenatal diagnosis for a variety of reasons, including:
- To manage the rest of her pregnancy in a more efficient way
- To determine her pregnancy’s outcome
- To plan for any possible complications regarding the birth process
- To plan for issues that could be present in the newborn
- To make sure the baby is born in the safest possible situation
- To identify any conditions that could affect future pregnancies
Along with the reasons listed above, New Jersey Perinatal Associates offers prenatal diagnostic procedures to expecting mothers who have had abnormal ultrasound findings or positive results from prenatal screening evaluations, or who have had previous pregnancies that were affected by a chromosomal condition. Diagnostic procedures are also recommended to those who are 35 years or older, have a family history of a specific genetic condition requiring diagnosis, or are looking for additional reassurance about the well-being of their pregnancy. Occasionally, testing is performed later in pregnancy to test for certain infections.
How We Test and Evaluate an Unborn Fetus at NJPA
Both 3D and 4D ultrasounds are used to diagnose structural aspects of a fetus while it still exists in the mother’s uterus, and they are a crucial part of diagnosing any issues with the fetus in the prenatal stages. Physicians use ultrasounds to routinely check the size, location, age, and number of fetuses in the womb, in addition to looking for present birth defects, the volume of amniotic fluid, and movement of the fetus. Ultrasounds can also detect breathing & heartbeats. During an ultrasound, a transducer and a handful of gel are used on the pregnant woman’s abdomen, which emits the image and audio of the fetus and its environment.
Some tests, such as amniocentesis and chorionic villi sampling (CVS), are invasive. At our offices in NJ, however, we also offer our patients NIPT – a simple blood test that is non-invasive to both you and your baby. NIPT, or non-invasive prenatal testing, can detect up to 99% of fetuses with Down syndrome, other chromosomal abnormalities like trisomy 18 and 13, and sex chromosome irregularities. With a higher success rate and lower false positive rate than other available screenings used in the first trimester, it has become an extremely common screening test for pregnant women.
Genetic Counseling in NJ
During the early stages of pregnancy, women may undergo genetic counseling, conducted by one of our genetic counselors on staff. A prenatal genetic questionnaire and review of your medical history will occur, and the counselor will discuss inherited medical traits from your family. After that takes place, a standard genetic analysis will determine the risks your child could have, and any birth defects or genetic conditions that may be more likely during your pregnancy. Your genetic counselor will talk to you about certain testing options, accompanying risks, benefits, and limitations. Genetic counseling is highly recommended for women age 35 or older, couples who are first cousins, those who have abnormal results from previous genetic screenings or tests, and those with a family history of inherited disorders.
Different from genetic counseling, genetic screening addresses a woman’s risk of giving birth to a baby with any chromosomal abnormalities and the conditions associated with them. Some genetic screenings are performed during the first trimester, usually between the 10th and 13th week of pregnancy, although they can be done in the second trimester as well. These tests evaluate the substances in a pregnant woman’s blood and an ultrasound of the fetus.
Chorionic Villus Sampling (CVS) and Amniocentesis at NJPA
Chorionic villus sampling (CVS) is a prenatal diagnostic test done in the first trimester. A sample of the placenta is removed either through the abdominal wall (transabdominal) or through the cervix (transcervical). Ultrasound guidance allows a thin tube or needle to retrieve the tissue sample, while safely monitoring your baby. Amniocentesis may be performed starting in the 16th week of pregnancy. This procedure involves removing a small amount of fluid from around the fetal sac and is performed with a needle.
All of our physician providers are experienced in performing CVS and amniocentesis. Along with our genetic counseling team, we will help you to understand the sampling results. Our health care team is here to support you and your loved ones if you are faced with difficult decisions.