Pregnant women can count on a number of things if they are receiving regular healthcare throughout the pregnancy including that they will be having a lot of appointments especially in the last few weeks of pregnancy and that they will be having quite a few prenatal testing right from the very beginning of the pregnancy right up to the delivery of the baby. One question that many pregnant women ask professions is: If my first trimester tests are all normal, why do I need more prenatal tests during my second trimester?
We all dream about becoming pregnant and just popping out a happy, healthy baby without having to have any discomfort in between the conception and birth but the reality is that there are a lot of physical discomfort involved in being pregnant including the prenatal testing that goes on during the pregnancy. We all understand that the prenatal tests are important because they are designed to monitor the health of the mom and the baby but we would prefer not to have to have them if all is well with the baby according to early tests. There are many reasons why prenatal testing in the second trimester is crucial to the health and well-being of the mom and baby.
The purpose of first trimester prenatal testing is to verify the pregnancy, confirm the viability of the pregnancy, date the pregnancy, and rule out any abnormalities of the fetus. Some of the more common first trimester testing that is done and can be reassuring to the woman includes free beta-hCG and PAPP-A, a detailed ultrasound which includes a NT measurement of the fetus, and urine tests for the presence of protein. Although these tests are designed to verify and assure the health of the fetus many of the second trimester tests are designed to give more information that health professions need to know in order to protect the mom and baby as well as to assure a safe and healthy delivery of the baby. Many of the first trimester screening tests cannot determine neural-tube defects such as spina bifida. The alphafetoprotein (AFP) test is a screening test that is done at 16 weeks. Most obstetricians recommend a high-quality level ultrasound at around 20 weeks of pregnancy. The second trimester of pregnancy starts at week 13 and ends at week 28.
According to the Palo Alto Medical Foundation Website, AFP (Alpha-Fetal Protein) or Serum Triple Test, Ultrasound, Amniocentesis and Glucose Tolerance Test are all important second trimester prenatal tests.
The AFP is important because it helps detect some of the defects known in pregnancy that the baby can develop such as Down syndrome, neural tube, trisomy 21, trisomy 18, and spina bifida. Blood tests can be done to perform the following tests:
AFP
uEST
hCG
The levels of hCG (human chorionic gonadotropin) typically start to drop during the second trimester and usually give an idea of viability when done in the first trimester.
Ultrasounds are performed during the second trimester so that professionals can evaluate the anatomy scan of the fetus. Ultrasounds can be ordered at anytime during the pregnancy but many healthcare professionals perform one around 18 to 20 weeks even in pregnancies that are normally progressing for many reasons including to determine the size, and fetal position as well as the amount of amniotic fluid and position of the placenta all important facts for delivery.
Amniocentesis is a prenatal test performed between the 14th and 17th week of pregnancy. The test can help medical professionals determine if the fetus has developed certain chromosomal abnormalities or other birth defects that can have serious consequences for the fetus or the mom. Typically this test is suggested if the mom is 35 years of age or older at conception. Many tests can be performed using the amniotic fluid including one to determine information regarding Rh incompatibilities between the blood types of the mom and fetus, genetic testing for the purpose of determining the presence of diseases such as Down syndrome, and tests to determine if the fetus is at risk for abnormal brain or nervous system defects such as neural tube defects.
The Glucose Tolerance test also called the GTT is a blood test. This test is done to determine the mom’s risk of developing gestational diabetes, a disease that can have an impact on the health of the mom and the fetus.
If the GTT reveals high results the pregnant woman will be asked to take another test known as the Oral glucose tolerance test or OGTT.
Although it takes time and may be uncomfortable to participate in these second trimester prenatal testing, the purpose of the tests are to determine the health of the fetus and to assure that everything will be done medically to assure a safe and healthy labor and delivery.
Source:
Palo Alto Medical Foundation. Your Second Trimester Testing and Exams http://www.pamf.org/pregnancy/second/prenatal.html