Finding out you are pregnant, especially with your first child, can be an exciting time filled with joy, wonder and apprehension. There is so much to learn, so much to do and so much to look forward to. Caring for yourself and ensuring the health of both you and the baby should be atop the list of priorities. In order to accomplish this, there are a number of tests that doctors recommend performing during the first trimester, or first three months, of pregnancy.
Blood Test
During your first prenatal doctor's visit, your doctor will perform a complete medical history and physical examination. Drawing blood to perform routine blood tests will be a part of this. A complete blood count, known as a CBC, provides information on the total number of white blood cells, red blood cells and platelets, revealing your overall health.
In addition, your blood will be tested for Rh factor. Rh is an antigen (a substance that stimulates the body's immune system) found on red blood cells. It is especially important for pregnant women to know if they are Rh positive, meaning the antigen is present, or Rh negative because if the baby is not the same, a condition known as Rh incompatability, serious health problems could arise in future pregnancies.
Ultrasound
An ultrasound is a non-invasive test that uses sound waves to produce a picture of the baby. In the first trimester, the ultrasound helps to determine the size, age and position of the embryo. During the first trimester it may be necessary to perform a transvaginal ultrasound, through a probe inserted in the vagina, to obtain a clear picture.
First Trimester Screen
The first trimester screen uses a combination of blood tests and ultrasound to determine the risk for specific chromosomal abnormalities. Although this test does not provide a definitive diagnosis, the American Pregnancy Association reports that it is the most accurate non-invasive test available. The test will not only identify chromosomal defects, including Down syndrome trisomy 21 and trisomy 18, but it also can also detect other abnormalities, such as cardiac disorders.
Chorionic Villus Sampling
Chorionic villus sampling, called CVS, is another test that can determine certain defects. The chorionic villus is the portion of the placenta that attaches to the lining of the uterus. The test is performed by removing a sample of the placenta through either a catheter through the cervix or needle through the abdomen. This test, which is performed between weeks 9 and 11, is usually recommended for women over the age of 35, because they are at increased risk for having a baby with genetic defects, according to the Palo Alto Medical Center. The test is not without disadvantages, as some women will experience minor bleeding following the procedure, and it does increase the risk for miscarriage.
