From: Reducing stillbirths: screening and monitoring during pregnancy and labour
Source | Location and Type of Study | Intervention | Stillbirths/Perinatal Outcomes |
---|---|---|---|
Reviews and meta-analyses | |||
Baschat et al. 2004 [49] | Germany, Netherlands, UK, USA, Spain, Sweden. Review. 8 studies included. N = 320 fetuses with normal Doppler, N = 202 with elevated ductus venosus (DV) Doppler indices (N = 101 with umbilical artery absent or reversed end-diastolic flow (UA A/REDV), N = 34 with DV reversed atrial velocity (DV-RAV). | Assessed association of umbilical artery Doppler and ductus venosus Doppler with perinatal outcome in preterm growth-restricted fetuses. | Perinatal mortality was 5.6% (16/282) with normal DV, 11.9% (12/101) with UA A/REDV, 38.8% (64/165) with abnormal DV and 41.2% (7/17) with DV-RAV |
Alfirevic and Neilson 1996 [50] | Australia, Sweden, UK (Chester, Edinburgh), South Africa (Tygerberg), Ireland (Dublin), Netherlands (Maastricht). Meta-analysis (Cochrane). 11 RCTs included (N = 6753 high-risk pregnant women). | Assessed the effects of Doppler umbilical artery waveform analysis (intervention) vs. no Doppler (controls) on obstetric care and fetal outcomes. | SBR: OR = 0.79 (95% CI: 0.46–1.34) [NS] [24/3325 vs. 31/3428 in intervention vs. control groups, respectively]. PMR: OR = 0.71 (95% CI: 0.50–1.01) [NS] [53/3433 vs. 75/3532 in intervention vs. control groups, respectively]. |
Intervention studies | |||
Baschat et al. 2003 [47] | Germany. Prospective cohort. N = 224 pregnancies with growth-restricted fetuses <37 weeks gestation. | Used logistic regression to assess the predictive ability of Doppler diagnosis of absent or reversed umbilical artery end-diastolic velocity, absence or reversal of atrial systolic blood flow velocity in the ductus venosus and pulsatile flow in the umbilical vein to predict stillbirth and perinatal mortality. | PMR: Umbilical artery waveform analysis most predictive compared to other Doppler modalities (R2 = 0.49, P < 0.001) SBR: Umbilical artery waveform analysis most predictive compared to other Doppler modalities(R2 = 0.48, P < 0.001). In cases of abnormal or reversed end-diastolic umbilical artery flow, venous pulsatility improved prediction of stillbirth. |
Giles et al; DAMP Study Group 2003 [52] | Australia, New Zealand, Southeast Asia. Tertiary level referral hospitals. Multi-centre RCT. Pregnant women (N = 526) with twin pregnancies at 25 wks gestation. | Compared the impact of Doppler ultrasound umbilical artery flow velocity waveform analysis (intervention) vs. no Doppler (controls) on pregnancy outcomes. Standard ultrasound biometric assessment in both arms. | Fetal death (miscarriage + SB): OR = 0.14 (95% CI: 0.01–1.31) [NS] [0/262 vs. 3/264 in intervention vs. control groups, respectively. PMR: 9/1000 vs. 11/1000 live births in intervention vs. control groups, respectively [NS] |
No authors listed 1997. [171] | France. 20 centres. Multicentre RCT. Low risk pregnant women (N = 3898) at 28 wks of gestation. | Compared the impact of umbilical Doppler 28–34 wks gestation (intervention) vs. no routine umbilical Doppler except in cases of clinical indication (controls). | SBR: OR = 0.40 (95% CI: 0.04–2.44) [NS] [2/1948 vs. 5/1943 in intervention vs. control groups, respectively]. PMR: OR = 0.33 (95% CI: 0.06–1.33) [NS] [3/1948 vs. 9/1943 in intervention vs. control groups, respectively]. |
Davies et al. 1992 [172] | UK (London). Single centre; unselected population. RCT. Singleton pregnancies (N = 2600) > 20 wks gestation. | Compared the impact of routine umbilical and uterine artery Doppler ultrasound to assess placental perfusion (intervention) vs. no Doppler (controls) on pregnancy outcomes. Standard ANC in both arms. | SBR: 11/1246 vs. 4/1229 in intervention vs. control groups, respectively. PMR (uncorrected): RR = 2.4 (95% CI: 1.00–5.76) [NS] [17/1246 vs. 7/1229 in intervention vs. control groups, respectively]. PMR (normally formed): RR = 3.95 (95% CI: 1.32–11.77). [16/1246 vs. 4/1229 in intervention vs. control groups, respectively]. |
Whittle et al. 1994 [173] | UK (Glasgow). RCT. Singleton pregnancies (N = 2986) < 26 wks gestation at 1st ANC visit. Doppler ultrasound at 26–30 wks and 34–36 wks gestation in all women. | Compared the impact of umbilical artery Doppler ultrasound revealed to clinician (intervention) vs. concealed from clinician (controls). | SBR: OR = 0.34 (95% CI: 0.10–1.07) [NS] [3 vs. 8 in intervention vs. control groups, respectively.] |
Observational studies | |||
Hugo et al. 2007 [48] | South Africa (Cape Town). Secondary hospital. Case series. Singleton pregnant women (N = 572) referred for suspected poor fetal growth. | Investigated the use of a personal computer- based, continuous-wave Doppler machine by a trained midwife to assess umbilical artery flow velocity waveforms with respect to the resistance indices (RIs). | PMR: [RIs < P75]: 13.2 [RIs: P75-95]: 39.1 [RIs > P95]: 41.7 SGA (%): [RIs < P75]: 27.2% [RIs: P75-95]: 41.2% [Ris > P95]: 55.6% |
Theron et al. 1992 [41] | South Africa. Prospective cohort study. Pregnant women (N = 127) with poor symphysis fundal growth (N = 39 abnormal Doppler flow velocimetry, N = 88 normal velocimetry). | Compared the impact of poor Doppler flow velocimetry of umbilical artery (exposed) with normal flow (unexposed). | PMR: OR = 33.2 (95% CI: 6.6–109.6; P < 0.000001). [43.6% vs. 2.3% in exposed vs. unexposed groups, respectively]. Fetal death (miscarriage + SB): [28.2% vs. 0% in exposed vs. unexposed groups, respectively; (P < 0.0005)]. |
Torres et al. 1995 [42] | Spain (Barcelona). Hospital Clinic. Prospective observational study over a 2-year period. Hypertensive pregnant women (N = 172; N = 166 with live births, N = 6 fetal deaths). | Assessed the use of umbilical artery Doppler in predicting SB. Compared the impact of absent (exposed) vs. normal end-diastolic velocity (unexposed). | SB: All had absence of end-diastolic velocity (sensitivity 100%). Fetal death (miscarriage + SB): 6/9 vs. 0/163 in absent vs. normal flow. Absent end-diastolic velocity in predicting fetal death: sensitivity: 100%, specificity: 98.2%, positive predictive value 66.7%, negative predictive value 100%. |