Performance of the first-trimester Fetal Medicine Foundation competing risks model for preeclampsia prediction: an external validation study in Brazil.

BACKGROUND: The current version of the Fetal Medicine Foundation competing risks model for preeclampsia prediction has not been previously validated in Brazil. OBJECTIVE: This study aimed (1) to validate the Fetal Medicine Foundation combined algorithm for the prediction of preterm preeclampsia in the Brazilian population and (2) to describe the accuracy and calibration of the Fetal Medicine Foundation algorithm when considering the prophylactic use of aspirin by clinical criteria. STUDY DESIGN: This was a cohort study, including consecutive singleton pregnancies undergoing preeclampsia screening at 11 to 14 weeks of gestation, examining maternal characteristics, medical history, and biophysical markers between October 2010 and December 2018 in a university hospital in Brazil. Risks were calculated using the 2018 version of the algorithm available on the Fetal Medicine Foundation website, and cases were classified as low or high risk using a cutoff of 1/100 to evaluate predictive performance. Expected and observed cases with preeclampsia according to the Fetal Medicine Foundation-estimated risk range (≥1 in 10; 1 in 11 to 1 in 50; 1 in 51 to 1 in 100; 1 in 101 to 1 in 150; and <1 in 150) were compared. After identifying high-risk pregnant women who used aspirin, the treatment effect of 62% reduction in preterm preeclampsia identified in the Combined Multimarker Screening and Randomized Patient Treatment with Aspirin for Evidence-Based Preeclampsia Prevention trial was used to evaluate the predictive performance adjusted for the effect of aspirin. The number of potentially unpreventable cases in the group without aspirin use was estimated. RESULTS: Among 2749 pregnancies, preterm preeclampsia occurred in 84 (3.1%). With a risk cutoff of 1/100, the screen-positive rate was 25.8%. The detection rate was 71.4%, with a false positive rate of 24.4%. The area under the curve was 0.818 (95% confidence interval, 0.773-0.863). In the risk range ≥1/10, there is an agreement between the number of expected cases and the number of observed cases, and in the other ranges, the predicted risk was lower than the observed rates. Accounting for the effect of aspirin resulted in an increase in detection rate and positive predictive values and a slight decrease in the false positive rate. With 27 cases of preterm preeclampsia in the high-risk group without aspirin use, we estimated that 16 of these cases of preterm preeclampsia would have been avoided if this group had received prophylaxis. CONCLUSION: In a high-prevalence setting, the Fetal Medicine Foundation algorithm can identify women who are more likely to develop preterm preeclampsia. Not accounting for the effect of aspirin underestimates the screening performance.

Application of 4 birthweight curves and local reference range at a University Hospital of Rio de Janeiro, Brazil.

BACKGROUND: Numerous fetal growth curves have been developed from various subpopulations and geographic locations worldwide. OBJECTIVE: To determine the birthweight standard at the Maternity School and compare it to currently used standards in the clinical practice services. STUDY DESIGN: Cross-sectional, observational, and descriptive study. Data from infants born between 2011 and 2016 were collected from the Maternity School Hospital of the Federal University of Rio de Janeiro to define the 10th, 25th, 50th, 75th, and 90th percentiles of the birthweight by gestational age. It was determined the performance of the INTERGROWTH-21st, Fenton, Alexander, and Lubchenco for the Maternity School standards. RESULTS: After the 33rd week of pregnancy, the INTERGROWTH standard was similar to the local standard for small-for-gestational-age infants and Fenton for large-for-gestational-age infants at Maternity School Hospital. The INTERGROWTH standard was found to be inadequate to classify small-for-gestational-age infants, which are babies at major risk for morbidity and mortality at the onset of the 33rd week of pregnancy. CONCLUSION: It was possible to define reference values for birthweight for the maternal school hospital considering at least 33 weeks of pregnancy with a 95% confidence interval. The comparison of the INTERGROWTH, Fenton, Alexander, and Lubchenko standards to the maternal school hospital curve showed that the Fenton curve was the most suitable for the diagnosis of small for gestational age.

The prevalence and perinatal repercussions of preeclampsia after the implementation of a prophylaxis protocol with aspirin.

OBJECTIVES: To evaluate the prevalence and perinatal repercussions of preeclampsia (PE) after the implementation of a prophylaxis protocol with aspirin in singleton pregnancy at Maternity School of Federal University of Rio de Janeiro, Rio de Janeiro, Brazil (2015-2106). METHODOLOGY: PE prevalence according to gestational age (GA) and the prevalence ratio (PR) between PE and prematurity, small for gestational age (SGA), and fetal death were calculated in patients assisted during 2015 and 2016. RESULTS: PE occurred in 373(10.75%) of 3468 investigated cases, where PE < 37 weeks was of 2.79% and PE greater than 37 weeks was of 7.95%. A total of 413 (11.9%) prematurity cases, 320 SGA (9.22%), and 50 fetal deaths (1.44%) occurred. In the PE group, 97 premature newborns (PR 0.90) and 51 SGA (PR 1.16) were born, and two fetal deaths occurred (PR 7.46). Concerning PE < 37 weeks, 27 SGA cases (PR 1.42) and two fetal deaths (PR 2.62) were observed. Regarding PE greater than 37 weeks, 24 SGA (PR 1.09) were born, and no fetal deaths were observed. Our findings were compared to previously published results. CONCLUSIONS: PE was significantly associated with SGA newborns, especially premature PE. Prescribing aspirin for PE prophylaxis based only on clinical risk factors in a real-life scenario does not appear to be effective but resulted in a PE screening and prophylaxis protocol review and update at ME/UFRJ.

External validation of first trimester combined screening for pre-eclampsia in Brazil: An observational study.

OBJECTIVE: To validate a combined algorithm for early prediction of pre-eclampsia (PE) in the Brazilian population. STUDY DESIGN: This is an unplanned secondary analysis of a cohort study. Consecutive singleton pregnancies undergoing first-trimester screening for PE involving examination of maternal characteristics, medical history, and biophysical markers were considered eligible. Women were classified as low-or high-risk using a cutoff of 1/200, but the individual risk was not used to dictate management, as aspirin prophylaxis was given to women based solely on clinical risk factors. Receiver-operating characteristics (ROC) curves for PE, preterm PE(PE < 37) and early 34(PE < 34) were constructed and detection rates(DR) and false-positive rates(FPR) were calculated, adjusting for the effect of aspirin. Propensity score analysis was utilized to account for possible confounding by indication. MAIN OUTCOME MEASURES: Screening performance and PE rates. RESULTS: Among 1695 women, 323(19.1%) were classified as high-risk for PE and 1372(80.9%) were considered low-risk. Aspirin use was registered in 62(3.7%) in the high-risk group and 33(1.9%) in the low-risk group. There were 164(9.7%) women who developed PE, including 41(2.4%) with PE < 37 and 18(1.1%) PE < 34.Subgroups with aspirin had higher incidence of PE, suggest confounding by indication. The algorithm had an AUC of 0.87, DR of 72% for PE < 34; an AUC of 0.8, DR of 59% for PE < 37, both with FPR of 18%. Accounting for effect of aspirin, we observed an improvement in DR of PE < 37 to 67%. CONCLUSION: Using combined predictive algorithm for preterm PE prediction is feasible in clinical practice in low/middle-income countries. Aspirin use needs to be accounted for when evaluating the performance of screening.