Prenatal tests during the second trimester would typically include different types of marker tests and also regular ultrasound scans to see the foetus is developing correctly.
The below list gives a comprehensive list of the most common tests that a mother has to undergo during the second trimester:
- Maternal serum alpha-fetoprotein (MSAFP) and multiple marker screening – One of these tests which are genetic screening tests are routinely offered to mothers during the second trimester.The MSAFP measure levels of alpha-fetoprotein produced by the foetus. Abnormal levels of hormones may indicate complications related to the foetus or placenta.These tests are known by different names owing to the test procedure. When the blood drawn for the MSAFP test is also used to check levels of the estriol hormone and hCG, it’s called the triple test.
When the marker called Inhibin-A is added to the screen, it is known as the quad marker test.
If a Rh negative mother is carrying a Rh positive baby, then there are chances that blood from the mother’s body would cross over to the placenta and cause harm to the baby.
- Ultrasound scans – This is a test that all parents eagerly await. Done somewhere around the 20th week, the ultrasound scans help in ascertaining the due date, checking for multiple births, detecting complications like placenta previa or slow foetal growth or other malformations like cleft palate.
New-age 3D scans can now show almost life-like 3D images of the developing baby.
- Fetoscopy – It is an endoscopic process that detects diseases or defects like amniotic band symptom, congenital diaphragmatic hernia etcetera. This process, however, carries risk to the mother and the foetus and is hence not a very commonly recommended process.
- Blood Glucose screening – This is also a typical second-trimester test done usually between the 24th and 28th This test is important to detect diabetes which can cause large babies and difficult deliveries.
- Foetal Doppler ultrasound – This ultrasound test uses sound waves to evaluate the type and pattern of blood flow through the blood vessels to the placenta.
- Amniocentesis – This is an optional test prescribed sometime between the 15th and 18th weeks, especially for women above 35, or women who have a higher-than-usual risk of contracting a genetic disorder, or for women whose multiple marker test results have yielded abnormal results.The analysis of this test, which involves inserting a needle through the mother’s abdomen into the amniotic sac and withdrawing fluid that contains foetal cells, can detect genetic disorders in almost 100 percent cases and neural tube defects in almost 99 percent of the cases.