Toal Meghana, Chaddha Vandana, Windrim Rory, Kingdom John
Department of Obstetrics and Gynaecology (Maternal-Fetal Medicine Division Placenta Clinic), Mount Sinai Hospital, University of Toronto, Toronto ON.
Department of Obstetrics and Gynaecology (Maternal-Fetal Medicine Division Placenta Clinic), Mount Sinai Hospital, University of Toronto, Toronto ON; Department of Medical Imaging, Mount Sinai Hospital, University of Toronto, Toronto ON.
J Obstet Gynaecol Can. 2008 Mar;30(3):198-206. doi: 10.1016/S1701-2163(16)32756-6.
We evaluated the role of placental morphology ultrasound and uterine artery Doppler in predicting adverse perinatal outcomes in women with unexplained elevated serum alpha-fetoprotein (AFP) or human chorionic gonadotropin (hCG) levels in the second trimester of pregnancy.
Women with a serum AFP > 2.0 MoM (n = 83) or serum hCG > 2.5 MoM (n = 68) had placental imaging at 19-23 weeks' gestation. Abnormal placental morphology (i.e., a maximum thickness of > 4 cm or > 50% of length) and abnormal uterine artery Doppler [UTAD] (mean pulsatility index > 1.45) were related to placental complications of pregnancy. Relative risks were derived for all women. Likelihood ratios were derived for the subset (55/83) in the group with elevated AFP who had no medical and/or obstetrical risk factors.
Compared with elevated serumh CG, an elevated serum AFP was associated with higher rates of perinatal mortality (15.6% vs. 4.3%), preterm birth at < 32 weeks' gestation (26.5% vs. 7.3%), small-for-gestational age (SGA) birth weight < 10th centile (24.1% vs. 10.3%) and severe intrauterine growth restriction (IUGR) (8.4% vs. 2.8%). Thirty-seven (44.5%) women with elevated serum AFP had an adverse perinatal outcome, and 23 of these women (67%) had no prior medical and/or obstetric risk factors. Abnormal tests of placental function were more common in the elevated serum AFP group than in the hCG group (UTAD 30.1% vs. 11.6%; placental morphology 30.2% vs. 16.2%). Abnormal UTAD and abnormal placental morphology had similar positive likelihood ratios for a range of adverse perinatal events in the elevated AFP group (1.3-4.4) and were increased when both tests were abnormal (likelihood ratio 5.0 for preeclampsia, 4.5 for preterm delivery < 32 weeks, 4.9 for intrauterine fetal demise). In the elevated hCG group abnormal UTAD and abnormal placental morphology predicted SGA (likelihood ratios 5.2 and 4.9) and IUGR (likelihood ratios 4.7 and 7.3) but did not predict preeclampsia or preterm birth.
Assessment of placental function using either morphology or UTAD at 19-23 weeks' gestation identifies a subset of women at increased risk of adverse perinatal events with an elevated serum AFP. These tests have more limited value in women with an elevated serum hCG because of the lower prevalence of adverse perinatal events.
我们评估了胎盘形态超声和子宫动脉多普勒在预测妊娠中期血清甲胎蛋白（AFP）或人绒毛膜促性腺激素（hCG）水平不明原因升高的孕妇围产期不良结局中的作用。
血清AFP>2.0倍中位数（MoM）（n = 83）或血清hCG>2.5 MoM（n = 68）的孕妇在妊娠19 - 23周时进行胎盘成像。胎盘形态异常（即最大厚度>4 cm或长度的>50%）和子宫动脉多普勒异常[UTAD]（平均搏动指数>1.45）与妊娠胎盘并发症相关。得出所有女性的相对风险。对AFP升高且无医学和/或产科风险因素的组中的子集（55/83）得出似然比。
与血清hCG升高相比，血清AFP升高与更高的围产期死亡率（15.6%对4.3%）、妊娠<32周的早产（26.5%对7.3%）、小于胎龄（SGA）出生体重<第10百分位数（24.1%对10.3%）以及严重宫内生长受限（IUGR）（8.4%对2.8%）相关。37名（44.5%）血清AFP升高的女性有围产期不良结局，其中23名女性（67%）无既往医学和/或产科风险因素。血清AFP升高组胎盘功能异常测试比hCG组更常见（UTAD 30.1%对11.6%；胎盘形态30.2%对16.2%）。在AFP升高组中，UTAD异常和胎盘形态异常对于一系列围产期不良事件具有相似的阳性似然比（1.3 - 4.4），当两项测试均异常时似然比增加（子痫前期似然比5.0，<32周早产似然比4.5，宫内胎儿死亡似然比4.9）。在hCG升高组中，UTAD异常和胎盘形态异常预测SGA（似然比5.2和4.9）和IUGR（似然比4.7和7.3），但不能预测子痫前期或早产。
在妊娠19 - 23周时使用形态学或UTAD评估胎盘功能可识别出血清AFP升高且围产期不良事件风险增加的一部分女性。由于围产期不良事件的发生率较低，这些测试在血清hCG升高的女性中的价值更有限。
