Second Trimester Prenatal Testing: An Ob-Gyn Shares What To Expect

Prenatal testing is important to monitor you and your baby’s health, but exactly what is involved in these screenings? Here, an obstetrician-gynecologist talks about what to expect during your second trimester prenatal visits, including what tests may be done, when they usually happen, what they look for, how they’re performed and what the results may mean. When is the second trimester? Before we can discuss second trimester prenatal visits, we need to answer the question, “When does the second trimester start?” According to Dr. Sudheer Jayaprabhu, an ob-gyn at Christus Health in Texas, most definitions of second trimester have it stretching from week 13 to week 28 of the pregnancy. Prenatal testing during the second trimester Quad screen This voluntary blood test performed between weeks 16 and 18 measures several hormones produced during pregnancy. These tests, also called multiple markers, calculate the potential risk for Down syndrome, neural tube defects like spina bifida and Trisomy 18, according to Stanford Medicine. These tests aren’t always accurate, but are used to see who might need more testing. If there is an abnormal result,” Jayaprabhu says, “genetic counseling and ultrasound are usually performed by a Maternal Fetal Medicine specialist.” Amniocentesis (placing a needle...