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Z Weinraub

Publications and source records attributed to Z Weinraub.

At least 19 recordsLinked to original sources
PubMed1999

Comparison of nuchal translucency measurement and second-trimester triple serum screening in twin versus singleton pregnancies.

Maternal serum screening for Down syndrome (DS) in twin pregnancies poses difficulties due to a lack of precise biochemical information about each co-twin. The current study attempts, for the first time, to compare two screening methods: nuchal translucency (NT) measurement and serum screening for DS, in twin pregnancies. 60 women with twin pregnancies (study group) underwent both first-trimester NT scanning and mid-trimester triple-marker serum screening, and were followed throughout their gestation. Nuchal translucency measurements were compared with a matched control of 120 singleton pregnancies with a similar (+/-2 years) maternal age and fetal crown-rump length (CRL) (+/-3 mm). In both analyses, a risk of 1:380, or higher, of having a DS newborn was considered screen positive. Both mean maternal age (31+/-3 years) and CRL (62+/-11 mm) were similar in the study and control groups. The median NT measurement expressed as multiples of the median (MOM) for CRL was similar in the study and control groups (0.85 and 0.88, respectively). Based on NT measurements, 5 per cent of the pregnancies in the study group and 2.5 per cent in the control group were defined as screen positive (p =N. S). Mid-gestation serum screening was associated with 15 per cent and 6 per cent screen-positive rate in study and control groups, respectively (p<0. 05). There was a ratio of 1:3 screen-positive rate between first and second-trimester screening tests within the study group. This high false-positive rate results led to 18.3 per cent amniocentesis rate in the study group compared with 7.5 per cent of the control group (p<0.03). Only one co-twin which was picked up by the NT screen was further diagnosed as trisomy 21, and one co-twin with cardiac and neural tube defect was missed by the two screening tests and was later picked up in an anomaly scan. Although the current series is too small to provoke any changes in screening practice, when twin pregnancies are diagnosed, it seems very reasonable to offer them NT measurement. A larger group may be needed to clarify which approach is the most beneficial screening policy for this highly selected group of pregnant women.

Adult↗
PubMed1999

Can nuchal cord cause transient increased nuchal translucency thickness?

When detected in a first trimester scan, an increased thickness of nuchal translucency (NT) may be associated with chromosomal, cardiac or genetic disorders. However, less attention has been devoted to the outcome of those fetuses who have confirmed normal anatomies and karyotyping, but have abnormal first trimester scans. Thus, a challenging new issue is how to counsel such cases of transient increased NT in which the translucency rapidly vanishes with no evidence of other underlying abnormalities. Two cases of transient increased thickness of NT are reported. In both, a nuchal cord was ultrasonographically demonstrated and a thorough work-up revealed chromosomally and anatomically normal fetuses. The pathophysiological theories behind these observations and their significance are discussed. Based on these observations, we suggest that transvaginal sonography combined with Doppler flow studies should be utilized for the presize detection of cord patterns to accomplish the work-up in cases of increased NT.

Adult↗
PubMed1999

The feasibility of nuchal translucency measurement in higher order multiple gestations achieved by assisted reproduction.

Nuchal translucency (NT) measurement for screening chromosomal abnormalities and detecting fetal anomalies is an effective ultrasonographic marker, originally developed for singleton pregnancies. This study sought to evaluate the feasibility of NT measurements in higher order multiple gestations. Pregnant patients who conceived following assisted reproduction and were carrying three or more fetuses were enrolled in the study. Each fetus was ultrasonographically assessed, a NT measurement was obtained, and the findings were used for counselling prior to any invasive procedure. In all, 24 pregnant patients, initially carrying 79 fetuses aged 10-14 weeks of gestation, were compared with 79 consecutively matched, singleton controls, naturally conceived, having similar crown-rump lengths (+/- 3 mm). NT measurements were feasible for both study and control fetuses, which exhibited similar NT measurements for 5th, 50th and 95th centiles. Also, mean NT thicknesses [measurements in mm or multiple of the medians (MOM)] were similar for both groups (1.41 +/- 0.41 and 1.35 +/- 0.39 mm respectively and 0.87 +/- 0.23 and 0.83 +/- 0.25 MOM respectively). Prenatally no chromosomal abnormalities were detected in either group, and, of those infants who had no karyotyping, no traits were observed that warranted chromosomal analysis. NT measurements are feasible in higher order multiple gestations. Since there is no other effective screening modality for these pregnancies, it seems reasonable to recommend NT measurement for antenatal screening services for higher order multiple gestations.

Chromosome Aberrations↗
PubMed1998

Image magnification does not contribute to the repeatability of caliper placement in measuring nuchal translucency thickness.

The objective of this study was to assess whether nuchal translucency image magnification contributes to the repeatability of caliper placement. Twenty-seven women undergoing first-trimester ultrasound screening at 11-14 weeks were examined by two qualified examiners. Fetal nuchal translucency thickness was measured twice by each examiner on a regular-sized image and subsequently on the same still image magnified. Intraobserver repeatability coefficients of the regular-sized images were 0.28 mm and 0.34 mm for examiners A and B, respectively. Identical intraobserver repeatability coefficients of 0.28 mm were attained for both examiners on the magnified images. Interobserver repeatability of regular-sized image measurements showed a significant difference (p < 0.01) but the mean difference (+/- standard deviation) of 0.10 (0.18) mm was negligible. Similarly, interobserver repeatability of the magnified-image measurements yielded a significant difference (p < 0.02), but again with a small mean difference of 0.13 (0.26) mm. There were also significant differences when regular-sized images and magnified images were compared for both examiners: 0.08 (0.16) mm for examiner A (p < 0.02) and 0.10 (0.17) mm for examiner B (p < 0.01). Our results demonstrate that nuchal translucency image magnification does not contribute to the reproducibility of the measurement. Despite significantly smaller mean values obtained from the magnified images, compared to the regular-sized measurements, those differences do not justify modification of the criteria for caliper placement on magnified images. Blind repeated measurements on a regular-sized and/or magnified image are recommended as a tool for self-assessment, quality control and training.

Female↗
PubMed1998

Nuchal translucency audit: a novel image-scoring method.

OBJECTIVE: The aim of this study was to evaluate the feasibility and reproducibility of a novel image-scoring method of first-trimester nuchal translucency measurement as an objective tool of ongoing audit and training. DESIGN: This was an independent evaluation of nuchal translucency images by three separate reviewers unaware of the examiner. SUBJECTS: There were 105 consecutive singleton pregnancies undergoing first-trimester screening. METHODS: Each image was scored according to the following criteria: section (oblique, 0; mid-sagittal, 2), caliper placing (misplaced, 0; proper, 2), skin line (nuchal only, 0; nuchal and back, 2), image size (unsatisfactory, 0; satisfactory, 1), amnion (not visualized, 0; visualized, 1) and head position (flexion/hyperextension, 0; straight, 1). The final score was categorized into one of four quality groups: excellent (8-9), reasonable (4-7), intermediate (2-3), unacceptable (0-1). RESULTS: The distributions of the four quality groups were similar between the three reviewers: 11.4% were classified as excellent, 57.1% as reasonable, 25.7% as intermediate and 5.7% as unacceptable. Inter-reviewer agreement showed identical classification, by each pair of reviewers, from 65.7% to 74.3%, and partial agreement to neighboring quality groups from 25.7% to 34.3% of the cases. In none of the cases did the reviewers differ in categorizing cases to remarkably different quality groups. Application of the auditing method to the examiners showed similar distribution to the various quality groups and similar mean final score of 4.69 (0.39, SE), 4.54 (0.15, SE) and 4.65 (0.15, SE). CONCLUSIONS: The described image-scoring method represents a new approach towards the evaluation of ultrasound performance as a whole and nuchal translucency measurement in particular. It may be employed by every center in an independent manner with minimal resources and regardless of the method of risk assessment. More studies will be needed to determine the standards required from the examiners and to elucidate the contribution of the proposed auditing method to the examination's quality and the process of training.

Female↗
PubMed1998

[Trisomy 18 anomalies on sonography and calculated risk of chromosomal abnormalities during first trimester].

Trisomy 18 is a chromosomal disorder giving multiple anomalies. Its frequency depends on maternal age. We report a 28-year-old woman in her first pregnancy, who underwent first trimester scanning for screening. Due to increased nuchal translucency and exomphalos, chorionic villous sampling was performed. Cytogenetic diagnosis was trisomy 18 and termination of pregnancy was carried out immediately.

Abortion, Induced↗
PubMed1996

Sonographic assessment of cervical changes during pregnancy and delivery: current concepts.

Correct detection of premature contractions and incompetent uterine cervix is still a challenging obstetrical problem since these factors remain a major cause of perinatal loss. Ultrasonography offers additional important data for the prediction of these pathologies which have common sonographic patterns; shortening of the cervical length, funneling of the membranes and dilatation of the endocervical canal. The first section of this review highlights sonography of normal cervical anatomy, while the second section focuses on recent advances in sonographic detection of premature contractions and incompetent cervix. It is believed that due to its accuracy and reproducibility, this noninvasive technique should become more integrated into this aspect of antenatal care.

Cervix Uteri↗
PubMed1996

Three-dimensional saline contrast hysterosonography and surface rendering of uterine cavity pathology.

A new technique that combines saline contrast hysterosonography with three-dimensional surface rendering for the visualization of uterine intracavitary pathologies is described. A total of 32 patients suspected of having uterine cavity pathologies on the basis of previous ultrasonography, hysterosalpingography or hysteroscopy were involved in the study. They were examined by three-dimensional high-frequency endovaginal probes (Combison 530, Kretztechnik, Zipf, Austria), with normal saline used as an expander and contrast medium. Three perpendicular planes could be evaluated simultaneous, and surface renderings were readily available. Following the instillation of normal saline, the uterine cavity appears as an echo-free, well-defined structure, and the endometrium appears as an echogenic homogeneous lining around the cavity. Data acquisition time is short and images can be stored for later evaluation. Surface rendering of polypoid structures shows echogenic masses on a pedicle protruding into the uterine cavity. Submucous fibroids appear as mixed echogenic sites bulging into the cavity. Intrauterine synechiae appear as bands of varying thickness traversing the uterine cavity. Simultaneous display of the zone of interest in three perpendicular planes enhances imaging capabilities, while surface rendering provides a comprehensive overview of the surface area of the findings and their topographical orientation. Further research using this new technique is required to document its real contribution to ultrasonographic imaging.

Contrast Media↗
PubMed1996

Late selective termination of fetal abnormalities in twin pregnancies: a multicentre report.

OBJECTIVE: To evaluate the outcome of late selective fetal termination based on combined data from eight tertiary perinatal centres. DESIGN: Israeli law requires institutional committee approval for pregnancy termination. Moreover, after 24 weeks only a district superior committee can approve the termination. A total of 36 bichorionic twin pregnancies who underwent selective fetal termination after 24 complete gestational weeks were identified in eight Israeli centres. RESULTS: In 23 women (63.9%) the indication for selective termination was structural anomaly, and in 13 (36.1%) the indication was chromosomal abnormality. The mean gestational age at the time of diagnosis was 24.1 +/- 1.9 weeks. The termination procedure was performed at a mean gestational age of 25.5 +/- 2.0 weeks (median 25, range 24-33 weeks). There was one case of immediate procedure-related complication (i.e. amnionitis) and the unaffected infant died, which was the only perinatal death in this series. No evidence of coagulopathy was reported. Only five women (13.8%) delivered before 34 completed weeks. The mean gestational age at delivery was 36.9 +/- 2.9 weeks (28-41 weeks), and the mean procedure-to-delivery interval was 11.8 +/- 3.2 weeks (median 13, range 3-17 weeks). CONCLUSIONS: Late (> 24 weeks) selective termination in twin pregnancies is associated with favourable perinatal outcome of the healthy twin. In countries where the law permits late pregnancy termination, the parents should be informed of that possibility.

Adult↗
PubMed1996

Serial color Doppler flow of uterine vasculature combined with serum beta-hCG measurements for improved monitoring of patients with gestational trophoblastic disease. A preliminary report.

Weekly serum beta-hCG measurements and transvaginal ultrasound scans coupled with color Doppler flow were performed on 8 patients with hydatidiform mole. Two patients later developed persistent trophoblastic disease, necessitating chemotherapy. The correlation coefficients between Doppler flow indices, systolic-diastolic (S/D) ratio and pulsatility index (PI) with log beta-hCG were -0.96 and -0.97, respectively. The weekly S/D and PI indices were plotted on an individual curve. Only the 2 patients who developed persistent gestational trophoblastic disease had PI index levels of < or = 1.5 as early as 2 weeks after molar evacuation. At that stage their serum beta-hCG levels were not different from some of the other patients. In this preliminary report, the regression of the disease could be reliably assessed by observing the changes in low resistance flow which paralleled the gradual decrements in serial beta-hCG levels. Thus, the contribution of this noninvasive imaging technique encourages the authors to further investigate Doppler flow monitoring among a larger sample of patients suffering from various gestational trophoblastic diseases.

Adult↗
PubMed1995

Placental isoferritin levels during first trimester of normal and complete molar gestations.

Serum placental isoferritin levels (PLF) levels were measured in 33 patients admitted for routine scanning of a first trimester normal singleton pregnancy and six patients who were hospitalized for uterine evacuation of a complete molar gestation. Venous blood was obtained upon admission and before curettage, when necessary. Serum was separated into glass tubes, immediately frozen and stored at -20 degrees C until analysed. The mean serum PLF levels were 18.1 (+/- 14) U/ml and 5.5 (+/- 2) U/ml for normal and molar gestations, respectively, with a significant difference between the two groups (P = 0.001). Sixty-seven per cent of normal pregnancies had serum PLF levels > or = 10 U/ml, whereas none of the molar gestation group reached this threshold level. Furthermore, the molar gestation group's low serum PLF levels remained unchanged throughout the entire follow-up period and until their beta-human chorionic gonadotrophin levels were undetectable. Unlike normal pregnancies, the molar trophoblast does not seem to secrete or synthesize PLF, suggesting that the complete molar placenta has different protein-producing capabilities when compared with those found in normal pregnancies. Further studies, including serum PLF among other categories of gestational trophoblastic neoplasms, are recommended before this data can be integrated into routine clinical work.

Biomarkers↗
PubMed1995

First trimester embryo reduction: a medical solution to an iatrogenic problem.

The incidence of multiple pregnancies is increasing, mainly as a consequence of the widespread use of various infertility protocols. Since such gestations present a high risk of feto-maternal morbidity and mortality, selective first trimester fetocide remains one of the few reasonable options. We reviewed the literature dealing with the outcome of 804 multiple pregnancies following the use of transcervical, transvaginal or transabdominal approaches. Questions relating to dealing with technical failure, method of fetocide and procedural improvements are examined. In a comparison of the variables: miscarriage, preterm delivery, perinatal and neonatal loss rates, the transvaginal approach fares better, but statistical significance (P < 0.001) is achieved only for preterm delivery. We speculated that this might be attributable to the very early gestational age at which the procedure is usually performed. However, the transabdominal approach offers better results when post-manipulation maternal morbidity is considered, i.e. infection and vaginal bleeding. Since each option offers different advantages and disadvantages, additional experience and larger population samples are required to further clarify this important issue.

Female↗
PubMed1995

Changes in uterine artery Doppler flow velocity waveforms during the third stage of labor.

Transabdominal Doppler velocity waveform measurements of the uterine arteries during the third stage of labor were performed upon 25 patients with uncomplicated vaginal deliveries and 5 with prolonged third stage in order to further assess third-stage mechanisms. Based on Doppler flow measurements, three phases of the third stage of labor were observed: (1) a latent phase with a systolic/diastolic ratio (S/D) and a pulsatility index (PI) of 2.14 +/- 0.49 and 0.89 +/- 0.17, respectively; (2) a contraction and detachment phase with an S/D and PI of 2.53 +/- 0.53 and 1.28 +/- 0.37, respectively, and (3) an expulsion phase with an S/D and PI of 2.20 +/- 0.34 and 0.91 +/- 0.20, respectively (p < 0.05). During the third stage of labor, it was shown that uterine contractions squeezed the uterine vessels as they traversed the myometrium, leading to an increase in the extrinsic resistance, which was reflected by high resistance flow. Following placental separation and changes in the placental-site wall, there was slight uterine relaxation resulting in decreased uterine vessel resistance. This observation encourages the authors to continue investigating the contribution of ultrasound and Doppler flow for studies of the postpartum period.

Adult↗
PubMed1995

Improved techniques for first-trimester fetal reduction using simultaneous abdominal and transvaginal ultrasonographic guidance. Preliminary report.

Simultaneous transabdominal injection of potassium chloride (KCl) assisted by transvaginal ultrasonographic guidance was evaluated in 5 patients who conceived due to various assisted reproductive techniques and ovarian stimulation. All 5 underwent first-trimester fetal reduction for multiplicity of high-order pregnancies. Four sets of triplets were reduced to twin, and 1 twin pregnancy was reduced to a singleton. Less than 2 ml of 2 mEq/ml KCl per fetus was needed for each case. No fetal or maternal complications nor technical failure attributable to the procedure were recorded. All pregnancies were delivered > or = 35 weeks of gestation. Transabdominal fetal reduction using simultaneous transvaginal ultrasonographic guidance for selective feticide combines the benefits of both the transabdominal and transvaginal approaches, mainly in selected cases in which some experts prefer the abdominal route, but find it technically difficult to practice. Further experience is needed to confirm our encouraging preliminary results before drawing any definitive conclusions.

Abdomen↗
PubMed1994

Prevention of pregnancy-induced hypertension in twins by early administration of low-dose aspirin: a preliminary report.

PROBLEM: Effectiveness of early administered low-dose aspirin in prevention of pregnancy-induced hypertension (PIH) and fetal growth retardation in twin pregnancies was investigated in a randomized placebo controlled, double-blind trial in 47 twin pregnancies. METHOD: Twenty-four women received 100 mg of aspirin daily from mean gestational age of 17.7 wk, and 23 women ingested placebo from a mean gestational age of 18 wk until delivery. The placebo and aspirin group were similar in age, weight gain, zygosity, gravidity, parity, and obstetrical antecedents. Treatment lasted for a mean period of 16.8 wk and 18.3 wk in the placebo and aspirin groups, respectively. The mean gestational age at birth was 35.0 wk and 36.4 wk in the placebo and aspirin groups, respectively. RESULTS: PIH was noted in six women (26%) in the placebo group, but in only one woman (4%) in the aspirin treated patients (P < .05). The mean combined fetal weights of both twins, and the mean weight of the second twin at delivery were significantly higher in the aspirin treated mothers than in the placebo treated gravidas (mean difference of 781 g, P < .02 and mean difference of 488 g, P < .005, respectively). Intrauterine growth retardation (< 10th percentile) concerned 11 (24%) and six (13%) fetuses in the placebo and aspirin groups, respectively. No adverse effects of treatment to either the mothers or the infants were noted. CONCLUSION: Low-dose aspirin reduces the incidence of PIH and has a beneficial effect on fetal growth in twin pregnancies. Additional clinical trials are needed in order to define and select subgroups of twins where aspirin treatment is recommended.

Adult↗