Question 1
Prenatal testing is done to identify health issues that may interfere with the developing fetus. Within the first trimester, what lab test is usually obtained?
- A. Blood type and Rh factor
- B. Amniocentesis
- C. Maternal serum Alpha-fetoprotein
- D. Group B strep (GBS) vaginal culture
Show answer and rationale
Correct answer: A — Blood type and Rh factor
During the first trimester of pregnancy, one of the essential lab tests obtained is the blood type and Rh factor. This test is crucial for identifying the mother's blood type and Rh factor, which helps in determining any potential blood incompatibility issues that could arise between the mother and the fetus. Identifying such issues early in pregnancy allows healthcare providers to take necessary precautions to prevent complications that could affect the developing fetus. Amniocentesis, maternal serum Alpha-fetoprotein, and Group B strep (GBS) vaginal culture are typically not performed in the first trimester. Amniocentesis is usually done later in pregnancy to test for genetic disorders, maternal serum Alpha-fetoprotein is part of second-trimester screening for neural tube defects, and Group B strep (GBS) vaginal culture is typically done closer to delivery to assess the risk of neonatal infection. Therefore, the correct answer is A: 'Blood type and Rh factor.'