The effectiveness of prenatal serum biomarker screening for neural tube defects in second trimester pregnant women: a meta-analysis.
BACKGROUND
Neural tube defects (NTDs) are common and serious birth defects all over the world. Prenatal screening for NTDs using maternal serum alpha-fetoprotein (MSAFP) during the second trimester of pregnancy has been widely used, but its effectiveness remains unclear.


METHODS
We evaluated the studies published in the English and Chinese on MSAFP screening for NTDs. The homogeneity of the studies was evaluated by the forest graph. Meta-analysis was applied to calculate the combined effect values and their 95% confidence intervals.


RESULTS
As many as 22 articles were selected according to the criteria and were included in the meta-analysis, for a total of 684,140 pregnant women screened during the second trimester. All the studies selected were homogenous according to the forest graph (chi(2) = 25.17, P > 0.10). The combined relative risk estimate was 0.25 and its 95% confidence interval was 0.21 to 0.29. The combined protective rate was 75%. The sensitivity and specificity of MSAFP screening were 75.1 and 97.7%, respectively.


CONCLUSIONS
Use of MSAFP during the second trimester in pregnant women is an effective measure for the screening of NTDs.
Wang
Zhi-Ping
ZP
Department of Epidemiology and Health Statistics, School of Public Health, Shandong University, Jinan, Shandong, China. zhiping9312@yahoo.cn
Li
Hui
H
Hao
Lian-Zheng
LZ
Zhao
Zhong-Tang
ZT
D015982:Bias; D015415:Biomarkers / Q000097:blood*; D001774:Blood Chemical Analysis / Q000379:methods / Q000592:standards; D004526:Efficiency; D005260:Female; D006801:Humans; D008403:Mass Screening / Q000379:methods; D009436:Neural Tube Defects / Q000097:blood / Q000175:diagnosis* / Q000453:epidemiology; D011237:Predictive Value of Tests; D011247:Pregnancy; D011262:Pregnancy Trimester, Second / Q000097:blood*; D011296:Prenatal Diagnosis / Q000379:methods* / Q000592:standards / Q000706:statistics & numerical data; D012680:Sensitivity and Specificity
D015415:Biomarkers