Middle cerebral artery peak systolic velocity to predict fetal hemoglobin levels in twin anemia-polycythemia sequence.

OBJECTIVE: To evaluate the diagnostic accuracy of middle cerebral artery peak systolic velocity (MCA-PSV) Doppler measurements in prediction of hemoglobin levels in twin anemia-polycythemia sequence (TAPS). METHODS: This study involved a consecutive cohort comprising monochorionic twin pregnancies complicated by TAPS managed at three European fetal medicine centers between 2005 and 2013. The accuracy of MCA-PSV, measured immediately prior to fetal hemoglobin (Hb) measurement by fetal or cord blood sampling, for prediction of anemia and polycythemia was assessed using 2 × 2 tables. RESULTS: A total of 116 measurements (74 recorded in donors and 42 in recipients) from 43 twin pregnancies complicated by TAPS were available for analysis. MCA-PSV multiples of the median (MoM) values correlated well with Hb levels (r = - 0.86; P < 0.001). The sensitivity of MCA-PSV ≥ 1.5 MoM to predict severe anemia (Hb deficit > 5 SD below the mean) in TAPS donors was 94% (95% CI, 85-98%); specificity was 74% (95% CI, 62-83%); positive and negative predictive values were 76% (95% CI, 65-85%) and 94% (95% CI, 83-98%), respectively. The sensitivity of MCA-PSV ≤ 1.0 MoM to predict polycythemia (Hb level > 5 SD above the mean) in TAPS recipients was 97% (95% CI, 87-99%); specificity was 96% (95% CI, 89-99%); positive and negative predictive values were 93% (95% CI, 81-97%) and 99% (95% CI, 93-100%), respectively. CONCLUSION: MCA-PSV measurement has high diagnostic accuracy for predicting abnormal Hb levels in fetuses with TAPS.

[Vasa previa: Of the diagnosis to neonatal prognosis]. / Vasa prævia: du diagnostic au pronostic néonatal.

Vasa previa is a rare complication of pregnancy (1/2000 to 1/6000) with a high fetal mortality rate (75 to 100%). We will discuss two case reports of vasa previa: the first was diagnosed before labor, while the second was during delivery. In the first case, the diagnosis of vasa previa was confirmed by a transvaginal ultrasound and color doppler, while the second case involved late diagnosis during delivery and after gross examination of the placenta. Risk factors for vasa previa are: low-lying placenta, bilobed or succenturiate lobed placenta, velamentous and in vitro fertilization (IVF). Antenatal diagnosis of vasa previa is crucial because it allows for prophylactic caesarean section and prevents severe Benckiser's hemorrhage responsible for a very high neonatal mortality.