Is MSAFP Still a Useful Test for Detecting Open Neural Tube Defects and Ventral Wall Defects in the Era of First-Trimester and Early Second-Trimester Fetal Anatomical Ultrasounds?

Abstract

Introduction: To evaluate whether maternal serum α-fetoprotein (MSAFP) improves the detection rate for open neural tube defects (ONTDs) and ventral wall defects (VWD) in patients undergoing first-trimester and early second-trimester fetal anatomical survey. Material and Methods: A cohort of women undergoing screening between 2005 and 2012 was identified. All patients were offered an ultrasound at between 11 weeks and 13 weeks and 6 days of gestational age for nuchal translucency/fetal anatomy followed by an early second-trimester ultrasound at between 15 weeks and 17 weeks and 6 days of gestational age for fetal anatomy and MSAFP screening. All cases of ONTD and VWD were identified via query of billing and reporting software. Sensitivity and specificity for detection of ONTD/VWD were calculated, and groups were compared using the Fisher exact test, with p < 0.05 as significance. Results: A total of 23,790 women met the criteria for inclusion. Overall, 15 cases of ONTD and 17 cases of VWD were identified; 100% of cases were diagnosed by ultrasound prior to 18 weeks' gestation; none were diagnosed via MSAFP screening (p < 0.001). First-trimester and early second-trimester ultrasound had 100% sensitivity and 100% specificity for diagnosing ONTD/VWD. Discussion: Ultrasound for fetal anatomy during the first and early second trimester detected 100% of ONTD/VWD in our population. MSAFP is not useful as a screening tool for ONTD and VWD in the setting of this ultrasound screening protocol.

Predictive Value of Second-Trimester Biomarkers and Maternal Features for Adverse Pregnancy Outcomes

“…AFP also was used to screen for open neural tube defects and ventral wall defects, a way of assessment that has been less required since the introduction of sophisticated ultrasound for first-trimester and early second-trimester fetal anatomical surveys [14] . In the present study, we aimed to investigate the association between elevated maternal second-trimester serum HCG and AFP levels and adverse obstetric outcome.…”

Impact on spina bifida screening of shifting prenatal Down syndrome maternal serum screening from the second trimester to the first

“…In a recent study of 17 cases of open NTD, Roman et al 19 showed that MSAFP did not improve the detection rate of open NTD in a cohort of patients with an ultrasound scan in the first trimester and at 15-18 weeks. However, among the 15 diagnosed cases of open NTD, there were only five cases of spina bifida, the others being anencephaly and exencephaly.…”

“…The number of cases of spina bifida diagnosed per year was similar over the study period, i.e. 250, 249 and 240 in 2009, 2010 and 2011. Median gestational age at diagnosis was 22 weeks [IQ [10][11][12][13][14][15][16][17][18][19][20][21][22][23]. Termination of pregnancy was performed in 91.9% of cases at a median gestational age of 23 +4 weeks [IQ 20 +4 -25].…”

Current controversies in prenatal diagnosis 2: for those women screened by NIPT using cell free DNA, maternal serum markers are obsolete

“…No additional cases were detected by elevated MS‐AFP. The authors concluded that MS‐AFP is not useful as a screening tool for NTDs and VWDs following this protocol Prediction of pregnancy complications: It has been claimed that maternal serum markers are key in the novel paradigm, which has been called ‘the inverted pyramid of care’.…”