Abstract：
OBJECTIVE: To determine whether serum placental growth factor (PlGF) at 19-23 weeks of gestation can improve the identification of risk for adverse outcomes.
METHODS: Prospective observational cohort study.
METHODS: Two English maternity units.
METHODS: Unselected singleton pregnancies attending routine ultrasound at 19-23 weeks of gestation.
METHODS: Outcomes ascertained by health record review. Diagnostic test properties evaluated clinical risk factors for pre-eclampsia (according to National Institute of Care Excellence) or fetal growth restriction (according to Royal College of Obstetricians and Gynaecologists), low PlGF at 19-23 weeks of gestation (<5th percentile) or both.
METHODS: Pre-eclampsia, gestational hypertension, stillbirth, birthweight below third percentile or neonatal intensive care unit (NICU) admission for ≥48 h.
RESULTS: In 30 013 pregnancies, risk factors were present in 9941 (33.1%), low PlGF was present in 1501 (5.0%) and both (\'two-stage\' screening) were present in 547 (1.8%) pregnancies. Risk factors detected 41.7%-54.7% of adverse outcomes, and could not meaningfully revise the risk (all positive likelihood ratios, +LR, <5.0; all negative likelihood ratios, -LR, ≥0.2). Low PlGF detected 8.5%-17.4% of adverse outcomes, but meaningfully increased risks (other than NICU admission) associated with delivery <37 weeks of gestation (+LR = 5.03-15.55); all -LRs were ≥0.2. \'Two-stage\' screening detected 4.2%-8.9% of adverse outcomes, with meaningful +LRs (6.28-18.61) at <37 weeks of gestation, except for NICU admission of ≥48 h, which had an +LR of 7.56 at <34 weeks of gestation; all -LRs were ≥0.2. No screening strategy meaningfully increased or decreased the detection of adverse outcome risk at term.
CONCLUSIONS: Clinical risk factor screening has a high screen-positive rate and a poor detection of adverse outcomes. False positives cannot be reduced by PlGF testing at 19-23 weeks of gestation; therefore, this cannot be recommended as a useful strategy on its own.
METHODS: Prospective observational cohort study.
METHODS: Two English maternity units.
METHODS: Unselected singleton pregnancies attending routine ultrasound at 19-23 weeks of gestation.
METHODS: Outcomes ascertained by health record review. Diagnostic test properties evaluated clinical risk factors for pre-eclampsia (according to National Institute of Care Excellence) or fetal growth restriction (according to Royal College of Obstetricians and Gynaecologists), low PlGF at 19-23 weeks of gestation (<5th percentile) or both.
METHODS: Pre-eclampsia, gestational hypertension, stillbirth, birthweight below third percentile or neonatal intensive care unit (NICU) admission for ≥48 h.
RESULTS: In 30 013 pregnancies, risk factors were present in 9941 (33.1%), low PlGF was present in 1501 (5.0%) and both (\'two-stage\' screening) were present in 547 (1.8%) pregnancies. Risk factors detected 41.7%-54.7% of adverse outcomes, and could not meaningfully revise the risk (all positive likelihood ratios, +LR, <5.0; all negative likelihood ratios, -LR, ≥0.2). Low PlGF detected 8.5%-17.4% of adverse outcomes, but meaningfully increased risks (other than NICU admission) associated with delivery <37 weeks of gestation (+LR = 5.03-15.55); all -LRs were ≥0.2. \'Two-stage\' screening detected 4.2%-8.9% of adverse outcomes, with meaningful +LRs (6.28-18.61) at <37 weeks of gestation, except for NICU admission of ≥48 h, which had an +LR of 7.56 at <34 weeks of gestation; all -LRs were ≥0.2. No screening strategy meaningfully increased or decreased the detection of adverse outcome risk at term.
CONCLUSIONS: Clinical risk factor screening has a high screen-positive rate and a poor detection of adverse outcomes. False positives cannot be reduced by PlGF testing at 19-23 weeks of gestation; therefore, this cannot be recommended as a useful strategy on its own.
摘要：
目的：确定妊娠19-23周的血清胎盘生长因子（PlGF）是否可以改善不良结局风险的识别。
方法：前瞻性观察性队列研究。
方法：两个英国产妇单元。
方法：未选择的单胎妊娠在妊娠19-23周时进行常规超声检查。
方法：通过健康记录审查确定的结果。诊断测试特性评估了先兆子痫（根据国家护理卓越研究所）或胎儿生长受限（根据皇家妇产科学院）的临床风险因素，在妊娠19-23周时低PlGF（<5百分位数）或两者兼而有之。
方法：先兆子痫，妊娠期高血压,死产,出生体重低于第三百分位数或新生儿重症监护病房（NICU）入院≥48小时。
结果：在30013次怀孕中，9941例(33.1%)存在危险因素，低PlGF在1501例(5.0%)妊娠中存在,而在547例(1.8%)妊娠中存在两种情况(两阶段筛查)。危险因素检测到不良后果的41.7%-54.7%，并且无法有意义地修改风险(所有正似然比，+LR,<5.0；所有负似然比，-LR,≥0.2)。低PlGF检测到8.5%-17.4%的不良结局，但与妊娠<37周(+LR=5.03-15.55)相关的风险显著增加(NICU入院除外);所有-LR均≥0.2.“两阶段”筛查检测到4.2%-8.9%的不良结局，在妊娠<37周时有意义的+LR（6.28-18.61），除NICU入院≥48小时外，妊娠<34周时的+LR为7.56；所有-LR均≥0.2。没有筛查策略有意义地增加或减少足月不良结局风险的检测。
结论：临床危险因素筛查具有较高的筛查阳性率和不良结局检测。在妊娠19-23周时，PlGF检测不能减少假阳性；因此，这不能被推荐为一个有用的策略。
方法：前瞻性观察性队列研究。
方法：两个英国产妇单元。
方法：未选择的单胎妊娠在妊娠19-23周时进行常规超声检查。
方法：通过健康记录审查确定的结果。诊断测试特性评估了先兆子痫（根据国家护理卓越研究所）或胎儿生长受限（根据皇家妇产科学院）的临床风险因素，在妊娠19-23周时低PlGF（<5百分位数）或两者兼而有之。
方法：先兆子痫，妊娠期高血压,死产,出生体重低于第三百分位数或新生儿重症监护病房（NICU）入院≥48小时。
结果：在30013次怀孕中，9941例(33.1%)存在危险因素，低PlGF在1501例(5.0%)妊娠中存在,而在547例(1.8%)妊娠中存在两种情况(两阶段筛查)。危险因素检测到不良后果的41.7%-54.7%，并且无法有意义地修改风险(所有正似然比，+LR,<5.0；所有负似然比，-LR,≥0.2)。低PlGF检测到8.5%-17.4%的不良结局，但与妊娠<37周(+LR=5.03-15.55)相关的风险显著增加(NICU入院除外);所有-LR均≥0.2.“两阶段”筛查检测到4.2%-8.9%的不良结局，在妊娠<37周时有意义的+LR（6.28-18.61），除NICU入院≥48小时外，妊娠<34周时的+LR为7.56；所有-LR均≥0.2。没有筛查策略有意义地增加或减少足月不良结局风险的检测。
结论：临床危险因素筛查具有较高的筛查阳性率和不良结局检测。在妊娠19-23周时，PlGF检测不能减少假阳性；因此，这不能被推荐为一个有用的策略。
