Second Trimester Screening of Preeclampsia Using Maternal Characteristics and Uterine and Ophthalmic Artery Doppler.

PURPOSE: To establish the performance of a multi-parametric test including maternal risk factors and maternal uterine and ophthalmic artery Doppler in the second trimester of pregnancy for the prediction of preeclampsia (PE). MATERIALS AND METHODS: We performed a prospective observational cohort study with pregnant women who underwent a second trimester morphology scan. Maternal uterine and ophthalmic artery Doppler examinations were performed in 415 singleton pregnancies between 18 and 23 weeks of gestation. Additional history was obtained through participant questionnaires, and follow-up occurred to the time of discharge post-delivery. The control and PE groups were compared to continuous variables using the Kruskal-Wallis test and to categorical variables using the Chi-square and Fisher exact tests. Univariate and multivariate logistic regression analyses were performed to determine the best model for the prediction of PE. RESULTS: 40 (9.6 %) pregnant women developed PE. We observed significant differences in the body mass index (BMI) (p < 0.001), parity (p < 0.001), mean arterial pressure (MAP) (p < 0.001), and pulsatility index (PI) of uterine artery Doppler (p < 0.001) between PE and control groups. The best model for the prediction of PE included maternal characteristics, MAP, maternal uterine and ophthalmic artery Doppler with area under receiver operating characteristics (ROC) curve of 0.710 (95 % confidence interval, 613 - 0.807) with a sensitivity of 45 % to a false-positive rate of 10 % and 35 % to a false-positive rate of 5 %. CONCLUSION: Maternal ophthalmic artery Doppler did not promote a significant increase in the PE detection rate during the second trimester scan.

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.

Renal Interlobar Vein Impedance Index as a First-Trimester Marker Does Not Predict Hypertensive Disorders of Pregnancy.

OBJECTIVES: 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. METHODS: Venous Doppler parameters of both maternal kidneys were studied in 214 pregnant women at gestational ages of 11 weeks to 13 weeks 6 days. Patients were classified according to outcomes related to hypertensive disorders. Detection rates and areas under receiver operating characteristic curves were determined for the maternal renal interlobar vein impedance index as a first-trimester predictor of preeclampsia and gestational hypertension. RESULTS: Among the 214 patients, 22 (10.3%) developed preeclampsia; 10 (4.7%) developed gestational hypertension; and 182 were unaffected by hypertensive disorders (controls; 85.0%). In the overall study population, there was no difference in the impedance index between the right (0.44; 95% confidence interval, 0.35-0.50) and left (0.43; 95% confidence interval, 0.35-0.53) sides (P = .86). The average impedance index did not differ among women destined to develop preeclampsia (0.46; 95% confidence interval, 0.38-0.57), gestational hypertension (0.39; 95% confidence interval, 0.33-0.46), or pregnancies uncomplicated by hypertensive disease (0.42; 95% confidence interval, 0.37-0.50; P = .15). Low detection rates and the area under the curve analysis demonstrated that the impedance index was not predictive of hypertensive disorders of pregnancy. CONCLUSIONS: The maternal renal interlobar vein impedance index should not be considered a first-trimester marker of hypertensive disorders of pregnancy.

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.

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.

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

BACKGROUND: The aim of this study was to establish normative data for ophthalmic artery Doppler variables in the first trimester of normal pregnancy. METHODS: Maternal ophthalmic artery Doppler signals were recorded in 409 singleton pregnancies at 11-14 weeks' gestation, in mothers presenting consecutively for routine antenatal care. Pulsatility and resistance indices (PI, RI), peak systolic velocity (PSV), first peak diastolic velocity (PD1), and peak ratio (PR) were measured. Quartile regression was used to estimate reference ranges in the late first trimester of pregnancy. RESULTS: Mean ± SD values for maternal ophthalmic artery Doppler parameters between 11 and 14 weeks' gestation were RI = 0.81 ± 0.12, PI = 2.06 ± 0.57, PSV = 36.41 ± 12.1, PD1 = 21.07 ± 7.62, and PR = 0.58 ± 0.11. All clinical and Doppler variables were normally distributed. PD1 values were higher in patients who smoked, and in those with diabetes or a history of pre-eclampsia. PR values were higher in patients with diabetes and chronic hypertension, and lower in the nulliparous; these values declined as gestation advanced from 11 to 14 weeks, whereas the other variables remained unchanged. CONCLUSIONS: We provide reference values for maternal ophthalmic artery Doppler variables in the first trimester of normal pregnancy.

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.