Quadruple Marker Test - Second Trimester is a screening test that is used in pregnancy to check the risk of certain chromosomal conditions and birth defects in the unborn baby. It does not require an invasive procedure (a small blood sample), can be used to help prepare for the possible child's need for genetic testing, and can be used to help guide the decision to consider more invasive tests, if required, and in the planning stages.

Recommendations are that this is carried out between 15 to 22 weeks of gestation, and ideally at 16-18 weeks of gestation. The test is useful for pregnant women who are older in age, have a previous family history of genetic diseases, abnormal ultrasound findings, and for anyone who would like additional information regarding their child's health in the uterus.

Some of the tests performed are Beta Human Chorionic Gonadotropin (β-hCG), Maternal Alpha-Fetoprotein (AFP), Unconjugated Estriol (uE3), and Inhibin A. Blood tests of these biomarkers are taken from the mother and used in addition to other factors such as maternal age, weight, and gestational age to assess the potential risk for certain fetal abnormalities.

This screening can be useful to assess for the possibility of chromosomal abnormalities (Down syndrome – Trisomy 21, Edwards syndrome – Trisomy 18, neural tube defects/spina bifida). In situations where further tests are required to establish a pregnancy, the test can reduce the number of in-depth tests required when investigating.

A crucial part of the second trimester prenatal tests, the Quadruple Marker Test determines the development and genetic status of a fetus. Early risk assessment helps to receive medical advice, and then medical tests and assistance with pregnancy management, leading to better maternal and foetal results.