An integrated model for the prediction of preeclampsia using maternal factors and uterine artery Doppler velocimetry in unselected low-risk women

OBJECTIVE: The purpose of this study was to develop a predictive model for preeclampsia. STUDY DESIGN: This was a prospective screening study for preeclampsia using uterine artery Doppler ultrasound in unselected low-risk singleton pregnancies at community hospitals in the UK (n = 32,157). Logistic regression models were developed and their predictive ability assessed using the area under the receiver operator curve (AROC). RESULTS: Six hundred twelve (2.0%) women developed preeclampsia, and 144 (0.5%) required early delivery (<34 weeks). A model using both maternal and ultrasound factors had an AROC of 0.798, which was higher than ultrasound alone (0.729, P < .0001) or maternal factors alone (0.712, P < .0001). In early onset disease, the ROC of ultrasound alone (0.922) was not significantly improved by adding maternal predictors (0.945, P = .27). In contrast, late onset disease was better predicted by the combined model (AROC 0.798) than ultrasound alone (AROC 0.729, P < .0001) or maternal factors alone (AROC 0.712, P < .0001). CONCLUSION: The combination of uterine artery Doppler ultrasound and maternal factors provided the best estimate of risk.     

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

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.     

Prediction of the small for gestational age twin fetus by Doppler umbilical artery waveform analysis

In 89 consecutive twin pregnancies, monthly Doppler ultrasound measurements were made of the umbilical artery blood flow velocity waveforms of each fetus. In total, 453 Doppler studies were performed. Of the 178 infants, 32 were small for gestational age (SGA); only 24 of the 82 SGA Doppler studies were abnormal, giving an overall sensitivity of the test in the prediction of the SGA fetus of 29% and a positive predictive value of 34%. Furthermore, neither the sensitivities nor the positive predictive values were above 50% in any of the gestational-age intervals individually studied. We conclude that Doppler study of umbilical artery flow velocities is not of much value in the prediction of SGA infants in twin pregnancies, although persistently absent end-diastolic velocities were associated with poor outcome.     

The clinical significance of Doppler umbilical artery velocimetry in the small for gestational age fetus

Fifty-four women who were delivered of small for gestational age infants were studied antenatally by serially continuous-wave Doppler velocimetry. Outcomes were compared in the normal and abnormal systolic/diastolic ratio groups. Seventy-eight percent had an abnormal systolic/diastolic ratio. The group with an elevated systolic/diastolic ratio had a significantly higher incidence of abnormal fetal heart rate, pregnancy-induced hypertension, oligohydramnios, cesarean section for fetal distress, and admission into the neonatal intensive care unit. One third of the newborns required intermittent positive pressure ventilation. Average birth weight and gestational age at delivery were significantly lower and there were six perinatal deaths in the group with an elevated systolic/diastolic ratio and none in the group with a normal systolic/diastolic ratio. These data suggest that the small for gestational age fetus with normal umbilical artery velocimetry is at significantly lower risk than are those with abnormal ratios. This implies that management of the small for gestational age fetus may now be aided by a functional classification based on the umbilical artery velocity waveform.     

Doppler velocimetry of the arcuate arteries in adolescent pregnant women: predictive value in small for gestational age newborn infants]

A prospective study on 25 adolescent pregnant women was carried out. A single measurement of the systolic-diastolic ratio (S/D) was taken using continuous Doppler on arcuate arteries on both sides of the uterus. All measurements were taken after the 16th week of amenorrhea. The relationship between Doppler velocimetry and birthweight was established. Seven newborns were small for gestational age. The sensitivity of this method was 94.4% and specificity was 57.1%. Positive predictive value was 80.0% while negative predictive value was 85.0%. The importance of measuring both arcuate arteries and determining the site of placental insertion for proper interpretation of results is stressed.     

Placental vascularization in early onset small for gestational age and preeclampsia

The objective was to determine whether chorionic villous vascularization is diminished in cases of early onset (<34 weeks) small for gestational age (SGA) and/or preeclampsia (PE). Placental morphometrical measurements were performed in 4 gestational-age-matched groups complicated by SGA, SGA with PE, PE, and spontaneous preterm delivery without SGA or PE as the reference group. Using a video image analysis system, in randomly selected intermediate and terminal villi, the stromal area and the following villous vascular parameters were manually traced and analyzed: number of total, centrally and peripherally localized vessels, vascular area, and vascular area density. No differences were observed in intermediate and terminal villous vascular area. Preeclampsia was associated with smaller terminal villous stromal area (reference 2299 μm2, SGA 2412 μm2, SGA + PE 2073 μm2, and PE 2164 μm2, P = .011), whereas SGA was associated with an increased terminal villous vascular area density (reference 26.1%, SGA 35.7%, SGA + PE 33.4%, and PE 32.0%, P = .029). Compared with preserved flow, lower terminal villous vascular area density was found in cases with absent or reversed end-diastolic (ARED) umbilical artery flow (39.3% vs. 30.3%, P = .013). These data demonstrate that villous vascularization was not influenced by PE, whereas in terminal villi an increased vascular area density was associated with SGA. Lower terminal villous vascular area density was associated with ARED flow in SGA pregnancies, indicating an increased risk of fetal compromise.     

Prediction of smallness for gestational age by maternal serum human chorionic gonadotropin levels and by uterine artery Doppler study

OBJECTIVES: To compare the utility of maternal serum human chorionic gonadotropin (MShCG) levels with that of uterine artery Doppler study in predicting small for gestational age (SGA) birth and pregnancy-induced hypertension (PIH). METHODS: MShCG assay and uterine artery Doppler study were performed in 359 consecutive pregnant women with singleton pregnancies. MShCG levels > or =2.0 multiples of the median at 15-18 weeks' gestation were considered to be elevated. An abnormal uterine artery Doppler velocimetry at 21-24 weeks' gestation was defined as a mean pulsatility index above the 95th percentile or the presence of an early diastolic notch in either uterine artery. The predictive values of MShCG levels and uterine artery Doppler velocimetry were evaluated for the risk of SGA birth and PIH. RESULTS: Forty-one subjects gave birth to SGA infants, and 20 developed PIH. Patients with MShCG elevation or abnormal uterine artery Doppler velocimetry showed a significantly higher incidence of SGA infants than the controls. The sensitivity and specificity of MShCG elevation for SGA birth were 17.1 and 93.4%, respectively, compared with abnormal uterine artery Doppler velocimetry, which had 24.4 and 94.3%, respectively. There was no significant difference between these methods. Elevated levels of MShCG and abnormal uterine artery Doppler velocimetry were not associated with PIH. CONCLUSION: Elevated levels of second-trimester MShCG were as sensitive and specific in predicting SGA births as abnormal uterine artery Doppler velocimetry.     

Prediction of superimposed preeclampsia using uterine artery Doppler velocimetry in women with chronic hypertension

OBJECTIVE: To assess the role of uterine artery (UtA) Doppler to predict superimposed preeclampsia in women with chronic hypertension. METHODS: In a cohort of 182 women with chronic hypertension, UtA Doppler studies were performed before 25 weeks (mean 19.7 +/- 2.1 weeks) and repeated later in pregnancy (mean 28.5 +/- 3.7 weeks). RESULTS: The incidence of preeclampsia was 13% (24/182). Rates of preeclampsia increased with advancing gestation of abnormal UtA Doppler: 7% when UtA Doppler were normal at early exam, 18% when abnormal at early exam, and 28% when abnormal at late exam (Chi-square for trend: P < 0.001). The rate of preeclampsia among 40 women with abnormal early but normal late UtA Doppler was similar to that of women with normal findings at early exam (8 vs 7%; P = 1.00). Logistic regression analysis showed that the ability of UtA Doppler to predict preeclampsia was independent from other variables [Odds Ratio (OR) 7.1, 95% Confidence Interval (CI) 2.6-18.9). Receiver operating characteristic (ROC) curve identified a UtA value of 0.58 as the optimal threshold for the prediction of preeclampsia. CONCLUSION: The later in pregnancy the abnormal UtA Doppler findings are observed, the greater the risk of preeclampsia. Normalization of UtA Doppler after 25 weeks reduces the risk of preeclampsia to 8%.     

Are small for gestational age infants at higher risk for intracranial lesions?

The association of small for gestational age (SGA) and central nervous system (CNS) abnormalities is controversial. Some reports suggest that SGA infants are at higher risk, whereas other data indicate that growth retardation may have a protective effect on the CNS. We compared the cranial ultrasound results of 197 SGA infants with 197 appropriate for gestational age (AGA) neonates, matched for gestation and gender, to determine if growth retardation is associated with a difference in ultrasound detectable CNS abnormalities. Infants with external dysmorphology or toxoplasmosis, rubella, cytomegalovirus, herpes simplex (TORCH) infections were excluded. We found 51 (26%) intracranial abnormalities in the SGA infants compared with 41 (21%) in the AGA controls (difference not significant). The most common lesions were hemorrhagic or ischemic, and the incidence was similar for both groups, 43 (22%) for SGA and 35 (18%) for AGA infants. The type and severity of hemorrhagic or ischemic lesions was also the same. Ventriculomegaly, not associated with hemorrhage, and structural lesions were also comparable, nine (5%) in the SGA and six (3%) in the AGA infants. We conclude that SGA infants without external dysmorphology or TORCH infections are not at increased risk for CNS abnormalities detectable by cranial ultrasound.     

Identification of patients at risk for preeclampsia with the use of uterine artery Doppler velocimetry and copeptin

Purpose: To investigate the relationship between maternal copeptin levels and uterine artery Doppler examination and progress of preeclampsia.

Materials and methods: A cross-sectional study was designed with women those were screened at 20?+?0 – 24+ 6 weeks’ gestation between May 2014 and August 2014. The obstetric records of all normotensive women were examined. Uterine artery Doppler velocimetry results and serum copeptin levels were measured. The patients were divided into two groups according to normal (n?=?67) and abnormal uterine artery Doppler (n?=?21) findings.

Results: Maternal age was significantly lower in group 1 (n?=?21, 23.9%) than in group 2 (n=?67, 76.1%) (p?p?=?0.002).

Conclusions: Copeptin levels are significantly higher in patients who develop preeclampsia.     

Decreased cerebrovascular resistance in small for gestational age infants

Using a transcutaneous Doppler technique we found a significantly lower cerebrovascular resistance and higher cerebral blood flow velocity indicating vasodilatation and increase of cerebral blood flow in small for gestational age infants compared with appropriate for gestational age infants during the first days of life. We speculate that these findings are due to a continuation of the fetal situation in which chronic hypoxia, mostly caused by pregnancy-induced hypertension, possibly causes a prostacyclin-induced vasodilatation.     

早发型重度子(癎)前期母体子宫动脉及胎儿血流动力学的研究

目的通过观察分析早发型重度子痢前期母儿血液动力学变化特点，结合其母儿预后，进一步探讨母儿血流动力学监测在早发型重度子痢前期的临床诊治及预后估计中的应用价值。方法采用前瞻性病例一对照研究方法，应用彩色多普勒超声对36例早发型重度子痢前期和72例正常同期孕妇进行血液动力学有关参数测定（包括UA-S／D、UA—PI、MCA—S／D、MCA-PI、UtA—S／D、UtA-PI），并结合其预后进行统计分析。结果在早发型重度子痢前期组和正常妊娠组，胎儿UA、MCA血流及孕妇UtA血流的S／D、PI值均随着妊娠的进展，呈逐渐下降的趋势，早发型重度子痢前期的UA—S／D，UA-PI，UtA-S／D，UtA-PI比正常妊娠时明显增高（P〈0．05），而MCA-S／D和MCA—PI在妊娠33周前则比正常妊娠组降低，妊娠33周后有显著性差异。当早发型重度子痢前期出现母胎血流动学变化时，围产儿不良结局的发生率高于正常妊娠组。本研究中有7例胎儿产前出现脐动脉舒张末期血流缺如（AEDV），全部合并FGR，围产儿死亡6例。结论母胎血流动学参数在早发型重度子痢前期时常发生明显的改变，并与不良的围产儿结局有关，AEDV的出现意味着胎儿循环已出现或临近失代偿阶段，警示预后不良。