First trimester placental volume is reduced in hypertensive disorders of pregnancy associated with small for gestational age fetus.

INTRODUCTION: Trophoblastic invasion and placental growth are critical for pregnancy outcome. The placental volume can be assessed by 3 D ultrasound using Virtual Organ Computer-aided Analysis (VOCAL). Epidemiological and clinical data suggest that there are two different clinical phenotypes of hypertensive disorders of pregnancy (HDP) that coexist at any gestational age: HDP associated to fetal growth impairment and HDP associated to appropriate for gestational age fetal growth. The aim of this study was to determine whether placental volume in the first trimester of pregnancy differs between women with HDP associated or not to fetal growth impairment and uncomplicated pregnancies. METHODS: This is a retrospective cross-sectional study of prospectively recruited data in which maternal characteristics, Doppler velocimetry of uterine arteries, and three-dimensional (3 D) volume of the placenta were collected at 11 + 1 - 13 + 6 gestational weeks. The placental quotient (PQ) was calculated as placental volume/crown rump length. RESULTS: In a 2-year period, we prospectively collected first trimester data of 1322 women. For the purposes of this cross-sectional study, 57 women that delivered a SGA fetus, 34 that developed HDP-AGA, and six that developed HDP-SGA, respectively, were included in the study as cases. The control group was made of 117 uncomplicated pregnancies. The PQ was higher in women with uncomplicated pregnancies (PQ median 16.36 cm3/cm) than in all other study groups (PQ in SGA: 13.02 cm3/cm, p < .001; PQ in HDP-AGA: 12.65 cm3/cm, p = .002; and PQ in women with HDP-SGA: 8.33 cm3/cm [IQR 6.50-10.13], p < .001). The lowest PQ was observed in women with HDP-SGA and was significantly lower than PQ in either women with SGA or those with HDP-AGA (p = .02 and p = .04, respectively). The mean uterine artery pulsatility index was the highest in women with HDP-SGA (median 2.30) compared to all other groups (uncomplicated pregnancies 1.48, p < .0001; women with SGA 1.59, p = .001; and women with HDP-AGA 1.75, p = .009). DISCUSSION: Our findings suggest that HDP associated with SGA is characterized by impaired placental growth and perfusion as soon as in the first trimester of pregnancy. The role of PQ, isolated or in association with other biophysical parameters, to predict HDP with fetal growth impairment remains to be evaluated.

The association of first trimester uterine arteries Doppler velocimetry with different clinical phenotypes of hypertensive disorders of pregnancy: a longitudinal study.

Introduction: Current classification of hypertensive disorders of pregnancy (HDP) is mostly based on temporal classification differentiating HDP according to early and late onset of the disease. However, epidemiological and clinical data suggest that there are two different clinical phenotypes of HDP that coexist at any gestational age: HDP associated to intrauterine growth restriction (HDP-IUGR) and HDP associated to appropriate for gestational age fetal growth (HDP-AGAf). The aim of the study was to evaluate the association of first trimester uterine arteries (UtA) by Doppler velocimetry, and maternal risk factors with HDP according to two different classifications: one based on gestational age at delivery (early- and late-HDP), and one based on longitudinal ultrasound evaluation of fetal growth (HDP-IUGR and HDP-AGAf), independently of the gestational age. Methods: Maternal characteristics and mean pulsatility index (PI) of UtA were collected at 11-13 gestational weeks. A longitudinal ultrasound follow-up of fetal growth in each trimester and clinical outcome were obtained in 4290 singleton pregnancies. Results: UtA-PI was significantly higher in women who developed HDP-IUGR (n = 22) and the odds ratio (OR) to develop HDP-IUGR from 25 to 39 weeks was 8.6 (p < .0001). HDP-AGAf (n = 112) was significantly associated with a higher BMI, multiparity, and maternal age, but not with UtA-PI (OR 1.3; p = .2). In women with an abnormal UtA-PI, the odds of developing early (n = 15) and late-HDP (n = 119) were 3.0 (p = .03) and 1.7 (p = .002), respectively. The AUCs for HDP-IUGR and early-HDP were 0.84 and 0.71, respectively. Discussion: UtA Doppler velocimetry in the first trimester was strongly associated with HDP-IUGR all along gestation, as a proxy of placental insufficiency, and showed no association with HDP-AGAf. Our findings suggest an efficacy of first trimester UtA Doppler velocimetry to identify HDP-IUGR independently of the gestational age, and a limited value for HDP not associated with intrauterine growth restriction (IUGR).

Bedside cardiovascular maternal interrogation in the first trimester to predict different phenotypes of hypertensive disorders in pregnancy.

OBJECTIVE: The aim is to evaluate if maternal cardiovascular indices, in the first trimester of pregnancy, might be useful to differentiate women who develop different hypertensive disorders of pregnancy (HDP). STUDY DESIGN: Method: 1399 pregnant women attending screening for chromosomal aneuploidies were recruited. The following parameters were measured: Doppler Velocimetry of uterine arteries; Peripheral blood pressure; Aortic Pressure derived from applanation tonometry. Primary outcome were: women who developed HDP associated with newborns with an appropriate weight for local gestational age standards (AGA) and women that developed HDP associated with a newborn weight below the 10th centile (SGA). RESULTS: Mean UtA PI was significantly higher in the HDP-SGA compared with controls. HDP-AGA showed a higher rate of family history of hypertension and a higher BMI. In HDP-AGA Brachial and Aortic mean pressure were higher than controls. The most significant contributors for all forms of HDP were mean UtA PI for HDP-SGA and mean arterial blood pressure for HDP-AGA. The multivariate logistic regression for HDP-SGA shows an AUC 0.88, whereas the AUC for the prediction of HDP-AGA group was 0.71. CONCLUSION: HDP-SGA were characterized by significantly higher values of UtA-PI, whereas HDP-AGA by mean aortic and brachial pressure and risk factors for endothelial dysfunction.

Assessment of coupling between trans-abdominally acquired fetal ECG and uterine activity by bivariate phase-rectified signal averaging analysis.

UNLABELLED: Couplings between uterine contractions (UC) and fetal heart rate (fHR) provide important information on fetal condition during labor. At present, couplings between UC and fHR are assessed by visual analysis and interpretation of cardiotocography. The application of computerized approaches is restricted due to the non-stationarity of the signal, missing data and noise, typical for fHR. Herein, we propose a novel approach to assess couplings between UC and fHR, based on a signal-processing algorithm termed bivariate phase-rectified signal averaging (BPRSA). METHODS: Electrohysterogram (EHG) and fetal electrocardiogram (fECG) were recorded non-invasively by a trans-abdominal device in 73 women at term with uneventful singleton pregnancy during the first stage of labor. Coupling between UC and fHR was analyzed by BPRSA and by conventional cross power spectral density analysis (CPSD). For both methods, degree of coupling was assessed by the maximum coefficient of coherence (CPRSA and CRAW, respectively) in the UC frequency domain. Coherence values greater than 0.50 were consider significant. CPRSA and CRAW were compared by Wilcoxon test. RESULTS: At visual inspection BPRSA analysis identified coupled periodicities in 86.3% (63/73) of the cases. 11/73 (15%) cases were excluded from further analysis because no 30 minutes of fECG recording without signal loss was available for spectral analysis. Significant coupling was found in 90.3% (56/62) of the cases analyzed by BPRSA, and in 24.2% (15/62) of the cases analyzed by CPSD, respectively. The difference between median value of CPRSA and CRAW was highly significant (0.79 [IQR 0.69-0.90] and 0.29 [IQR 0.17-0.47], respectively; p<0.0001). CONCLUSION: BPRSA is a novel computer-based approach that can be reliably applied to trans-abdominally acquired EHG-fECG. It allows the assessment of correlations between UC and fHR patterns in the majority of labors, overcoming the limitations of non-stationarity and artifacts. Compared to standard techniques of cross-correlations, such as CPSD, BPRSA is significantly superior.

Fetal and maternal heart rate confusion during intra-partum monitoring: comparison of trans-abdominal fetal electrocardiogram and Doppler telemetry.

OBJECTIVE: To compare intra-partum performance of trans-abdominal electrocardiogram with Doppler telemetry. METHODS: In this prospective longitudinal study, simultaneous monitoring with trans-abdominal ECG and Doppler telemetry was performed in 41 uncomplicated term singleton pregnancies during labour. RESULTS: The overall success rate for FHR monitoring was similar between trans-abdominal ECG and Doppler telemetry (88.5 ± 16.7% vs 89.4 ± 7.6%), except for the second stage of labour. A significantly higher rate of confusion (p < 0.001) between fetal and maternal heart was found for Doppler telemetry (4.5 ± 4.5%) compared with trans-abdominal ECG (1.3 ± 1.9%), especially in the second stage and during maternal movements. CONCLUSIONS: Trans-abdominal ECG monitoring is feasible, with comparable success rate to traditional Doppler telemetry, without interfering with maternal mobility or requiring midwife intervention. The reduction in maternal\fetal heart rate confusion from trans-abdominal ECG could reduce incorrect obstetric interpretation.