Cusick W, Rodis J F, Vintzileos A M, Albini S M, McMahon M, Campbell W A
Department of Obstetrics and Gynecology, University of Connecticut Health Center, Farmington, USA.
J Reprod Med. 1996 May;41(5):327-32.
To determine if a correlation exists between the level of maternal serum alpha-fetoprotein (MSAFP) elevation and the rate of adverse pregnancy outcome, to examine the timing of pregnancies ending in fetal or neonatal death, and to develop a protocol for antepartum surveillance in an effort to prevent these adverse outcomes.
Singleton pregnancies with a single second-trimester elevated MSAFP > or = 2.0 multiples of the median (MoM) were eligible if a targeted ultrasound evaluation (< 24 weeks) was in agreement with the dates and no fetoplacental anomaly was detected. Three groups were established based on the second-trimester MSAFP elevation: 2.0-2.49, 2.5-2.99 and > or = 3.0 MoM.
Among the 383 patients enrolled, delivery data were available on 333 infants. Stratified by MSAFP elevations of 2.0-2.49, 2.5-2.99 and > or = 3.0 MoM, the rates of adverse pregnancy outcome were: (1) preterm birth: 14.3%, 15.6%, 20.3%; (2) small for gestational age at birth: 7.4%, 11.1%, 22.2%; and (3) perinatal deaths (neonatal and fetal): 2.6%, 3.3%, 5.6%. Seven pregnancy losses (three neonatal and four fetal deaths) occurred prior to 28 weeks. Of these seven, six fetuses exhibited intrauterine growth retardation by 23-26 weeks' gestation, and five of six were associated with MSAFP levels > or = 2.5 MoM. Four losses (two neonatal and two fetal deaths) occurred after 28 weeks. Of these, three involved structurally normal infants with normal growth who died after 34 weeks. All three of these pregnancies exhibited MSAFP elevations < 2.5 MoM.
In pregnancies with an unexplained elevated second-trimester MSAFP, the rate of adverse pregnancy outcomes is increased with higher elevations. Any proposed program to improve pregnancy outcome in patients with unexplained MSAFP elevations must include efforts aimed at preventing preterm delivery, repeat ultrasound at 24-26 weeks to rule out early-onset intrauterine growth retardation in pregnancies with elevations > or = 2.5 MoM and fetal biophysical monitoring, even in normally grown fetuses, instituted at 32 weeks to detect fetuses at risk for intrauterine death.
确定母血清甲胎蛋白（MSAFP）升高水平与不良妊娠结局发生率之间是否存在相关性，研究妊娠结局为胎儿或新生儿死亡的时间，并制定一项产前监测方案以预防这些不良结局。
如果孕中期单次MSAFP升高≥2.0倍中位数（MoM）的单胎妊娠，其靶向超声评估（<24周）与孕周相符且未检测到胎儿胎盘异常，则符合入选标准。根据孕中期MSAFP升高水平分为三组：2.0 - 2.49、2.5 - 2.99和≥3.0 MoM。
在纳入的383例患者中，有333例婴儿的分娩数据可用。按MSAFP升高水平2.0 - 2.49、2.5 - 2.99和≥3.0 MoM分层，不良妊娠结局发生率如下：（1）早产：14.3%、15.6%、20.3%；（2）出生时小于胎龄：7.4%、11.1%、22.2%；（3）围产期死亡（新生儿和胎儿）：2.6%、3.3%、5.6%。7例妊娠丢失（3例新生儿死亡和4例胎儿死亡）发生在28周之前。在这7例中，6例胎儿在孕23 - 26周时出现宫内生长受限，其中6例中有5例与MSAFP水平≥2.5 MoM相关。4例丢失（2例新生儿死亡和2例胎儿死亡）发生在28周之后。其中，3例涉及结构正常且生长正常的婴儿，他们在34周后死亡。这3例妊娠的MSAFP升高均<2.5 MoM。
在孕中期MSAFP不明原因升高的妊娠中，升高水平越高，不良妊娠结局的发生率越高。任何旨在改善MSAFP不明原因升高患者妊娠结局的方案都必须包括预防早产的措施，对MSAFP升高≥2.5 MoM的妊娠在24 - 26周进行重复超声检查以排除早发型宫内生长受限，以及在32周进行胎儿生物物理监测，即使是生长正常的胎儿，以检测有宫内死亡风险的胎儿。
