Course : MOC Part IV: Evaluation of Abnormal Maternal Serum Screening
It is appropriate to offer all prenatal patients aneuploidy assessment either through screening or diagnostic testing. If a patient opts for aneuploidy screening, this may be accomplished through first trimester, integrated or sequential screening beginning in the first trimester or, in the second trimester, through triple or quadruple screening. The results of the screening refines a patient’s age related risk for Down syndrome and other aneuploidies. Patients identified to be at increased risk for fetal aneuploidy through any of these screening methods requires further evaluation, including confirmation of gestational age, sonographic evaluation of fetal anatomy, and prenatal diagnosis.
Aneuploidy screening that incorporates second trimester analytes include maternal serum alpha fetoprotein (MSAFP) which can identify fetuses at risk for open fetal defects, such as neural tube abnormalities, omphalocoele, or gastroschisis, as well as rarer disorders such as congenital nephrosis. It can also signal an unsuspected multiple gestation or fetal demise. Patients with unexplained elevations in MSAFP remain at risk for adverse pregnancy outcomes including intrauterine growth restriction, placental abruption, or stillbirth.
The management of a patient with abnormal maternal serum screening results requires confirmation of the patient’s gestational age, and review of her family, medical, and pregnancy histories. The patient should undergo counseling regarding the clinical implications and significance of the increased risk, and access to a more definitive evaluation for the fetal condition. The discussion should include the benefits and risks of available testing, as well as the importance of the information to the patient. Targeted prenatal imaging for fetal anomalies and invasive diagnostic testing (chorionic villus sampling or amniocentesis) are routinely offered to patients with abnormal serum screening based on the serum screening results.
ACMG Members and ACMG Trainees ($25)
Counsel patients and document abnormal maternal serum screen.