Regular Pregnancy Tests Segregated by Trimesters
Prenatal tests are a crucial part of pregnancy, designed to monitor the health of both mother and baby. These medical tests, performed throughout pregnancy, serve to assess maternal health risks, detect genetic or structural abnormalities, and ensure the baby's optimal development.
First Trimester (Weeks 10–13)
The first trimester is an important period for prenatal testing. Several tests are conducted during this phase to ensure the baby's development is on track and to identify any potential risks.
- Nuchal Translucency (NT) Ultrasound: This ultrasound measures fluid at the back of the baby's neck to assess the risk of chromosomal abnormalities like Down syndrome.
- Double Marker Test (Maternal Blood Test): This test measures pregnancy-associated plasma protein-A (PAPP-A) and human chorionic gonadotropin (hCG); abnormal levels can indicate genetic risks when combined with the NT scan.
- Non-Invasive Prenatal Testing (NIPT): This blood test analyses fetal DNA circulating in maternal blood for chromosomal disorders, and can be done as early as 10 weeks.
- Carrier Screening: This optional genetic screening of parents for inherited conditions helps identify potential risks.
- Detailed First-Trimester Ultrasound (DFTU): High-resolution anatomy scans at 12–13 weeks detect structural anomalies early, especially in high-risk pregnancies.
- Confirmatory Pregnancy Blood Tests and Ultrasound: These tests confirm pregnancy, check the fetal heartbeat, and estimate gestational age.
Second Trimester (Around 18–22 Weeks)
The second trimester is another crucial period for prenatal testing. Tests during this phase focus on detecting structural anomalies, monitoring fetal growth, and screening for genetic disorders.
- Anatomy Scan Ultrasound: This detailed fetal anatomy survey detects structural anomalies and confirms fetal growth.
- Triple or Quad Marker Tests (Maternal Blood Tests): These tests measure substances like alpha-fetoprotein (AFP), estriol, hCG, and inhibin-A to screen for neural tube defects and chromosomal conditions.
- Screening for Gestational Diabetes and Anemia: These tests are typically performed at 24–28 weeks.
- Amniocentesis (Invasive Diagnostic Test): This optional diagnostic test analyses fetal chromosomes and DNA, usually after abnormal screening results or high-risk factors; it is performed in the second or third trimester.
Third Trimester
The third trimester focuses on monitoring fetal growth and wellbeing, as well as maternal health.
- Follow-up Ultrasounds: These ultrasounds monitor fetal growth and wellbeing as needed.
- Amniocentesis or Cordocentesis: Invasive tests may be performed in select cases for diagnosing certain conditions or fetal blood sampling.
- Routine Blood and Urine Tests: These tests monitor maternal health parameters and detect complications.
Prenatal tests are essential for early identification of potential genetic disorders, fetal structural issues, maternal complications, and for guiding further diagnostic or management decisions. Most screening tests are non-invasive and safe for both mother and fetus, while invasive tests provide definitive diagnoses but carry some risk.
Some additional tests include the Second Trimester Screening Test, which screens for Down syndrome and neural tube defects like anencephaly and spina bifida, and is performed between the 16th and 18th week of pregnancy. Electronic foetal heart monitoring tracks the baby's heart rate during pregnancy, labour, and delivery to determine the baby's well-being. The Integrated or Sequential Screening uses a combination of ultrasound images and blood tests to determine the risk of Down syndrome, spina bifida, brain disorder, and spinal cord disorder.
These tests are vital in ensuring a healthy pregnancy and baby. Every woman who goes through pregnancy needs routine prenatal testing. Non-routine tests are recommended for women with high-risk pregnancies, such as women who are over 35 years of age, teens, have had a premature baby, have a family history of genetic conditions, or have other risk factors.
