Yaron Y, Hamby D D, O'Brien J E, Critchfield G, Leon J, Ayoub M, Johnson M P, Evans M I
Center for Fetal Diagnosis and Therapy, Hutzel Hospital/ Wayne State University, Detroit, Michigan 48201, USA.
Am J Med Genet. 1998 Jan 23;75(3):297-9. doi: 10.1002/(sici)1096-8628(19980123)75:3<297::aid-ajmg14>3.0.co;2-k.
Increased levels of second trimester maternal serum alpha-fetoprotein (MSAFP) have long been established as a marker for neural tube defects (NTDs). In addition, decreased levels of maternal estriol in the third trimester have been reported in pregnancies with anencephalic fetuses. The purpose of this study was to evaluate whether early second trimester unconjugated serum estriol (uE3) is an independent predictor of NTDs. The study included 57,031 patients who underwent maternal serum screening with MSAFP at 14-22 weeks gestation. Of these, 23,415 also had uE3 measurements. There were 63 cases of NTD, an overall incidence of 1.1 per 1,000. Elevated MSAFP (> or =2.5 MOM) was detected in 1,346 patients, 48 of which had NTDs. Decreased uE3 (< or =0.5) was detected in 1,437 patients, 17 of which had NTDs. The incidence of NTDs was significantly higher in patients with low uE3, compared to patients with normal/high uE3 (1.15% vs. 0.09%, P < 001). Finally, 51 patients had both increased MSAFP and decreased uE3; 16 of these had NTDs, 14 of which were anencephalics. In conclusion, both elevated MSAFP and low maternal serum estriol are predictive of NTD but have a low sensitivity. The combination of abnormally elevated MSAFP and low estriol is highly predictive of NTD in particular anencephaly.
孕中期母体血清甲胎蛋白（MSAFP）水平升高长期以来一直被确立为神经管缺陷（NTDs）的一个标志物。此外，据报道无脑儿妊娠中孕晚期母体雌三醇水平降低。本研究的目的是评估孕中期早期未结合血清雌三醇（uE3）是否为NTDs的独立预测指标。该研究纳入了57031例在妊娠14 - 22周接受MSAFP母体血清筛查的患者。其中，23415例还进行了uE3检测。有63例NTDs病例，总发病率为每1000例中有1.1例。1346例患者检测到MSAFP升高（≥2.5中位数倍数），其中48例患有NTDs。1437例患者检测到uE3降低（≤0.5），其中17例患有NTDs。与uE3正常/高的患者相比，uE3低的患者中NTDs的发病率显著更高（1.15%对0.09%，P<0.001）。最后，51例患者MSAFP升高且uE3降低；其中16例患有NTDs，14例为无脑儿。总之，MSAFP升高和母体血清雌三醇降低均为NTDs的预测指标，但敏感性较低。MSAFP异常升高与雌三醇降低相结合对NTDs尤其是无脑儿具有高度预测性。
