Sammya Bezerra Maia e Holanda Moura

Prevention of Preeclampsia

Preeclampsia (PE) affects around 2–5% of pregnant women. It is a major cause of maternal and perinatal morbidity and mortality. In an attempt to prevent preeclampsia, many strategies based on antenatal care, change in lifestyle, nutritional supplementation, and drugs have been studied. The aim of this paper is to review recent evidence about primary and secondary prevention of preeclampsia.

Pre-Implantation Genetic Screening Techniques: Implications for Clinical Prenatal Diagnosis

Chromosomal aneuploidy is responsible for a significant proportion of pregnancy failures, whether conceived naturally or through in vitro fertilization (IVF). In an effort to improve the success rate of IVF, screening embryos for aneuploidy - or pre-implantation genetic screening (PGS) - has been proposed as a means of ensuring only euploid embryos are selected for transfer. Early PGS approaches were based on fluorescence in situ hybridization testing, and have been shown not to improve live birth rates. Recent developments in genetic testing technologies - such as next-generation sequencing and quantitative polymerase chain reaction, coupled with embryo biopsy at the blastocyst stage - have shown promise in improving IVF outcomes, but they remain to be validated in adequately powered, prospective randomized trials. The extent to which IVF with PGS lowers the a priori risk of aneuploidy in ongoing pregnancies so conceived has been poorly described, rendering it difficult to incorporate the potential benefit of PGS into existing prenatal aneuploidy screening regimens such as cell-free DNA testing or conventional combined nuchal translucency and maternal biochemistry assessment. Further data on the sensitivity and specificity of various forms of molecular PGS testing would improve our understanding of the effectiveness and accuracy of these technologies. This, in addition to further research into methods of risk combination and assessment, would allow us to help our patients make better- informed decisions about whether or not to proceed with invasive diagnostic tests.

Reference values of maternal ophthalmic artery doppler variables in the first trimester of normal pregnancy.

The aim of this study was to establish normative data for ophthalmic artery Doppler variables in the first trimester of normal pregnancy.

TNF-R1 as a first trimester marker for prediction of pre-eclampsia

Abstract Objective: To examine whether the maternal serum concentration of the soluble receptor-1 of tumor necrosis factor-α (TNF-R1) at 11–13 + 6 weeks of gestation is a predictor of development of pre-eclampsia (PE). Methods: This is a nested case–control study in which the concentration of TNF-R1 at 11 + 0 to 13 + 6 weeks was measured in 426 pregnant women in the first trimester. TNF-R1 values were expressed as multiples of the median (MoM) adjusted for maternal factors. The distributions of log TNF-R1 MoM in the control group and hypertensive disorders (early-PE [ePE], late-PE [lPE] and gestational hypertension [GH]) groups were compared. Logistic regression analysis was used to determine whether maternal factors, TNF-R1 or their combination make a significant contribution to the prediction of PE. Screening performance was determined by analysis of receiver–operating characteristics curves. Results: Median concentration of TNF-R1 (ng/ml) was higher in ePE (2.62 ± 0.67), lPE (2.12 ± 0.56) and GH (2.19 ± 0.45) compared to controls (2.04 ± 0.42), p = 0.001. Logistic regression analysis demonstrated that the addition of TNFR-1 to maternal factors did not make a significant contribution to the prediction of PE. Conclusions: The maternal serum TNF-R1 concentration at 11–13 + 6 weeks of gestation was increased in pregnancies which developed hypertensive disorders, however, the addition of TNFR-1 did not improve the detection rate of these conditions compared with maternal factors alone.

Comparison of three algorithms for prediction preeclampsia in the first trimester of pregnancy

OBJECTIVE To compare a new simple algorithm for preeclampsia (PE) prediction among Brazilian women with two international guidelines - National Institute for Clinical Excellence (NICE) and American College of Obstetricians and Gynecologists (ACOG). METHODS We performed a secondary analysis of two prospective cohort studies to predict PE between 11 and 13+6weeks of gestation, developed between August 2009 and January 2014. Outcomes measured were total PE, early PE (<34weeks), preterm PE (<37weeks), and term PE (≥37weeks). The predictive accuracy of the models was assessed using the area under the receiver operator characteristic curve (AUC-ROC) and via calculation of sensitivity and specificity for each outcome. RESULTS Of a total of 733 patients, 55 patients developed PE, 12 at early, 21 at preterm and 34 at term. The AUC-ROC values were low, which compromised the accuracy of NICE (AUC-ROC: 0.657) and ACOG (AUC-ROC: 0.562) algorithms for preterm PE prediction in the Brazilian population. The best predictive model for preterm PE included maternal factors (MF) and mean arterial pressure (MAP) (AUC-ROC: 0.842), with a statistically significant difference compared with ACOG (p<0.0001) and NICE (p=0.0002) guidelines. CONCLUSION The predictive accuracies of NICE and ACOG guidelines to predict preterm PE were low and a simple algorithm involving maternal factors and MAP performed better for the Brazilian population.

Simple approach based on maternal characteristics and mean arterial pressure for the prediction of preeclampsia in the first trimester of pregnancy

Abstract Aim: To propose a simple model for predicting preeclampsia (PE) in the 1st trimester of pregnancy on the basis of maternal characteristics (MC) and mean arterial pressure (MAP). Methods: A prospective cohort was performed to predict PE between 11 and 13+6 weeks of gestation. The MC evaluated were maternal age, skin color, parity, previous PE, smoking, family history of PE, hypertension, diabetes mellitus and body mass index (BMI). Mean arterial blood pressure (MAP) was measured at the time of the 1st trimester ultrasound. The outcome measures were the incidences of total PE, preterm PE (delivery <37 weeks) and term PE (delivery ≥37 weeks). We performed logistic regression analysis to determine which factors made significant contributions for the prediction of the three outcomes. Results: We analyzed 733 pregnant women; 55 developed PE, 21 of those developed preterm PE and 34 term PE. For total PE, the best model was MC+MAP, which had an area under the receiver operating characteristic curve (AUC ROC) of 0.79 [95% confidence interval (CI)=0.76–0.82]. For preterm PE, the best model was MC+MAP, with an AUC ROC of 0.84 (95% CI=0.81–0.87). For term PE, the best model was MC, with an AUC ROC of 0.75 (0.72–0.79). The MC+MAP model demonstrated a detection rate of 67% cases of preterm PE, with a false-positive rate of 10%, positive predictive value of 17% and negative predictive value of 99%. Conclusion: The MC+MAP model showed good accuracy in predicting preterm PE in the 1st trimester of gestation.

Renal interlobar vein impedance index as a first-trimester marker does not predict hypertensive disorders of pregnancy

The purpose of this study was to examine whether the maternal renal interlobar vein impedance index as assessed by first‐trimester sonography is able to predict the later development of hypertensive disorders of pregnancy.

D1. Renal interlobar vein impedance index (RIVI) as a first trimester marker for prediction of hypertensive disorders of pregnancy.

Abstract Objective: To examine whether the maternal renal interlobar vein impedance index (RIVI) as assessed by first trimester ultrasonography is able to predict the later development of hypertensive disorders of pregnancy. Methods: Venous Doppler parameters of both maternal kidneys were studied in 214 pregnant women at 11 + 0 to 13 + 6 weeks’ gestation. Subjects were classified according to the outcomes related to hypertensive disorders. Detection rates and areas under receiver operating characteristic (ROC) curves were determined for the maternal RIVI impedance as a first trimester predictor for preeclampsia (PE) and gestational hypertension (GH). Results: Among the 214 patients, 22 developed PE (10.3%), 10 developed GH (4.7%), and 182 were unaffected by hypertensive disorders (controls) (85%). In the overall study population, there was no difference in the RIVI between the right (0.44; 0.35–0.50) and left side (0.43; 0.35–0.53), p¼0.86. The average RIVI did not differ among women destined to develop PE (0.46; 0.38–0.57), GH (0.39; 0.33–0.46), or pregnancies uncomplicated by hypertensive disease (0.42; 0.37–0.50), p¼0.16. Area under ROC curve analysis demonstrated that RIVI was not predictive of hypertensive disorders of pregnancy. Conclusion: Maternal RIVI should not be considered a first-trimester marker of hypertensive disorders of pregnancy.

Predicting small for gestational age in the first trimester of pregnancy using maternal ophthalmic artery Doppler indices

Abstract Objective: To assess the capacity of maternal ophthalmic Doppler indices for predicting small for gestational age (SGA) newborns in the first trimester of pregnancy. Methods: We performed a prospective observational cohort study involving 499 singleton pregnancies during the first trimester scan (11–14 weeks). The following maternal ophthalmic Doppler indices were assessed: pulsatility index (PI), first diastolic peak velocity (PD1) and peak ratio (PR) = PD1/peak systolic velocity. We considered SGA all newborns with weight below 10th percentile. We used chi-square test (χ2) to compare the groups. We used area under receiver operating characteristics (ROC) curves with 95% confidence intervals (CI) and detection rate of 5% of false positive of each maternal ophthalmic Doppler index and the mean uterine artery PI for prediction SGA. Results: 27 (5.4%) patients delivered SGA newborns, 12 (2.4%) patients developed preeclampsia (PE) and delivered SGA newborns, and 460 had uneventful pregnancies (controls). We observed significant difference of PI and PR between SGA (SGA and SGA+PE) and control groups, p = 0.043 and p = 0.014, respectively. To 5% of false positive, the detection rate of SGA (SGA and SGA+PE groups) using PI, PD1 and PR were 14.8, 3.7, 14.8, 16.7, 16.7 and 16.7%, respectively. Mean uterine PI was significantly higher in the SGA+PE group (p = 0.003). Conclusion: The isolated use of maternal ophthalmic Doppler indices or in combination with uterine artery Doppler, in the first trimester of pregnancy, was not efficient to predict SGA newborns.

Brachial artery flow mediated dilation and pulsatility index change as independent predictors for hypertensive disorders in the second trimester of pregnancy

OBJECTIVE To assess brachial artery flow mediated dilatation (FMD) and pulsatility index change (PIC) as independent parameters for prediction hypertensive disorders (preeclampsia - PE and gestational hypertension - GH) in the second trimester of pregnancy. STUDY DESIGN We performed a prospective cohort study with 372 singleton pregnant women who underwent routine second trimester morphology scan. FMD and PIC were measured immediately after the ultrasound scan using the following formulas: FMD (%)=[(post occlusion arterial diameter-baseline arterial diameter)/baseline arterial diameter]×100 and PIC (%)=[(pulsatility index pre-pulsatility index post)/pulsatility index pre]. The control and hypertensive disorder groups were compared using the Kruskal-Wallis to continue variables and Chi-square and Fisher exact tests to categorical variables. We assessed the predictive accuracy of FMD and PIC by the area under the receiver operating characteristics (ROC) curve with its respective 95% confidence interval (CI). RESULTS We did not observe statistical difference between control and hypertensive disorder groups regarding the FMD and PIC (p=0.17 and p=0.38, respectively). Areas under ROC curve for prediction of GH using FMD and PIC were 0.59 (CI95% 0.48-0.71) and 0.60 (CI95% 0.47-0.73), respectively. Areas under ROC curve for prediction of PE using FMD and PIC were 0.55 (CI95% 0.46-0.64) and 0.52 (CI95% 0.61-0.69), respectively. CONCLUSION Brachial artery FMD and PIC as independent parameters did not show good prediction for hypertensive disorders in the second trimester of pregnancy.