First-trimester sonographic prediction of obstetric and neonatal outcomes in monochorionic diamniotic twin pregnancies

OBJECTIVES

The purpose of this study was to investigate whether discordant nuchal translucency and crown-rump length measurements in monochorionic diamniotic twins are predictive of adverse obstetric and neonatal outcomes.

METHODS

We conducted a multicenter retrospective cohort study including all monochorionic diamniotic twin pregnancies with two live fetuses at the 11-week to 13-week 6-day sonographic examination who had serial follow-up sonography until delivery. Isolated nuchal translucency, crown-rump length, and combined discordances were correlated with adverse obstetric outcomes, individually and in composite, including the occurrence of 1 or more of the following in either fetus: intrauterine growth restriction (IUGR), twin-twin transfusion syndrome (TTTS), intrauterine fetal death (IUFD), growth discordance (≥ 20%), and preterm birth before 28 weeks' gestation. Correlations with adverse composite neonatal outcomes were also studied. A receiver operating characteristic curve analysis and a logistic regression analysis with a generalized estimating equation were conducted.

RESULTS

Fifty-four of the 177 pregnancies included (31%) had an adverse composite obstetric outcome, with TTTS in 19 (11%), IUGR in 21 (12%), discordant growth in 14 (8%), IUFD in 14 (8%), and preterm birth before 28 weeks in 10 (6%). Of the 254 neonates included in the study, 69 (27%) were complicated by adverse composite neonatal outcomes, with respiratory distress syndrome being the most common (n = 59 [23%]). The areas under the curve for the combined discordances to predict composite obstetric and neonatal outcomes were 0.62 (95% confidence interval, 0.52-0.72), and 0.54 (95% confidence interval, 0.46-0.61), respectively.

CONCLUSIONS

In our population, nuchal translucency, crown-rump length, and combined discordances in monochorionic diamniotic twin pregnancies were not predictive of adverse composite obstetric and neonatal outcomes.

Systematic review of sonographic findings of placental mesenchymal dysplasia and subsequent pregnancy outcome

OBJECTIVE

To describe the sonographic features and pregnancy outcomes of placental mesenchymal dysplasia (PMD), an entity often misdiagnosed as molar pregnancy.

METHODS

We reviewed PMD cases from our institution and performed a systematic review of the existing literature. Inclusion criteria for the review were diagnosis of PMD as defined by placental pathology, description of placental morphology on antenatal ultrasound and reporting of pregnancy outcomes.

RESULTS

We found three cases of PMD at our institution. Patient 1 had elevated human chorionic gonadotropin (hCG) and an enlarged, hydropic placenta at 13 weeks, suggestive of a molar pregnancy. Patient 2 also had elevated hCG with large, vascular placental lakes on ultrasound suggesting placenta accreta or molar pregnancy. Case 3 involved placentomegaly and fetal anomalies suggestive of Beckwith-Wiedemann syndrome. From the literature review, 61 cases met the inclusion criteria. The most common sonographic features included enlarged (50%) and cystic (80%) placenta with dilated chorionic vessels. Biochemical aneuploidy screening abnormalities were relatively common as were fetal anomalies, Beckwith-Wiedemann syndrome and other genetic abnormalities. Pregnancy complications included intrauterine growth restriction (IUGR; 33%), intrauterine fetal death (IUFD; 13%), and preterm labor (33%). Pregnancies without fetal anomalies, IUGR, IUFD or preterm labor had normal neonatal outcomes despite PMD (9%).

CONCLUSIONS

The differential diagnosis of PMD includes molar pregnancy and other placental vascular anomalies. PMD is associated with adverse pregnancy outcome, so heightened surveillance with genetic evaluation, serial growth scans and third-trimester assessment of wellbeing should be considered. PMD must be differentiated from gestational trophoblastic disease because management and outcomes differ.

Fetus papyraceus in dichorionic diamniotic twin pregnancy: a case report

INTRODUCTION

The actual rate of multiple pregnancies is significantly larger than that observed during labor due to the fact that in the course of pregnancy intrauterine death of one or more fetuses may occur.

CASE PRESENTATION

A twenty-six old woman (GII, PII) reported to hospital in 26 weeks of DC/DA twin gestation complicated by intrauterine death of one fetus in the second trimester of a spontaneous pregnancy. Pregnancy ended at term with vaginal birth of a single live fetus. After birth, entanglement of the fetal umbilical cord around the leg of the dead fetus was discovered. It was the most probable cause of death.

CONCLUSIONS

Conservative management is preferred in case of intrauterine demise of one of the fetuses in DC/DA twin pregnancy. One of the reasons of fetal death may be entanglement of the umbilical cord around fetal small parts. The time of fetal death can be determined on the basis of the length of the thigh bone (Femur Length - FL).

Virtual autopsy by computed tomographic angiography of the fetal heart: a feasibility study

OBJECTIVE

To determine the feasibility of postmortem computed tomographic (pm-CT) angiography for fetal heart evaluation.

METHODS

Following termination of pregnancy (TOP) or intrauterine fetal death (IUFD) beyond 18 weeks' gestation, 33 fetuses were examined by pm-CT; in eight contrast medium was injected through the umbilical cord and in 25 contrast medium was injected directly into the heart. Logistic regression analysis was used to investigate the effect on the ability to visualize cardiac structures on pm-CT angiography of gestational age at TOP or delivery following IUFD, the time delay between fetal death and examination, the technique used for contrast-medium injection, the presence of cardiac abnormalities and whether or not there was IUFD. The diagnostic accuracy of pm-CT angiography for the evaluation of fetal cardiac structures was also evaluated.

RESULTS

Cardiac anatomy including heart situs, the four-chamber view and great vessels could be visualized on pm-CT angiography in 29 out of 33 fetuses (87.9%). Logistic regression analysis showed that the ability to visualize cardiac structures on pm-CT angiography was positively correlated only with contrast medium injected directly into the heart. Twenty-five out of the 33 fetuses underwent conventional autopsy. There were five cases with suspected major cardiac abnormality at prenatal ultrasound and one with a minor cardiac abnormality. In one of these cases, severe leakage into the pleural cavity did not allow for visualization of any heart structure on pm-CT angiography and in another invasive autopsy was declined. In two of the remaining four cases, the findings on pm-CT angiography and invasive autopsy were in agreement, while in two a ventricular septal defect was found on invasive autopsy but not on pm-CT. None of the 27 cases with normal hearts was falsely classified as abnormal using pm-CT angiography.

CONCLUSION

Pm-CT angiography by direct injection into the heart seems to be a feasible method for its evaluation. The extent to which such a technique could be used for the evaluation of congenital heart disease as an alternative to classical postmortem autopsy remains to be determined.

Decreased echogenicity of the embryo is correlated with absence of cardiac activity

PURPOSE

The purpose of this study was to investigate whether the sonographic echogenicity of embryos is associated with cardiac activity in utero.

METHODS

The present study reviewed a total of 164 embryos having a gestational age between 6 and 8 weeks. These embryos were examined by transvaginal ultrasonography and a comparison of their echogenicity was made with respect to those of the placenta and the myometrium. Grade II embryos were less echogenic than the placenta or had similar echogenicity with the myometrium, whereas grade I embryos shared the same echogenicity as the placenta. In contrast, grade III embryos were less echogenic than the myometrium.

RESULTS

Most of the embryos with cardiac activity were detected to have grade II echogenicity (78/130, 60.0%), whereas the remaining embryos had grade I echogenicity (52/130, 40.0%). In contrast, most of the embryos without cardiac activity had grade III echogenicity (20/34, 58.8%), whereas the remaining embryos had either grade II (8/34, 23.5%) or grade I (6/34, 17.7%) echogenicity.

CONCLUSIONS

Decreased echogenicity of embryos on grayscale ultrasound in the early first trimester is correlated with an absence of cardiac activity.

Prediction of intrauterine fetal death in small-for-gestational-age fetuses: impact of including ultrasound biometry in customized models

OBJECTIVE

Customized growth charts derived from maternal demographic characteristics alone have been shown to improve the prediction of pregnancy complications compared to population growth curves. We sought to estimate the impact of adding ultrasound biometric parameters to the customized chart for the prediction of intrauterine fetal death (IUFD).

METHODS

A retrospective cohort study was undertaken using an ultrasound database including singleton pregnancies followed between 16 and 20 weeks' gestation. After exclusion of preterm births, congenital anomalies, multifetal pregnancies and stillbirths (excluded only from derivation samples), we identified 59 016 births, divided into derivation (34 832) and validation (24 184) samples. Coefficients for significant physiological and pathological variables affecting fetal growth were derived using backward stepwise multiple regression (Cust-chart). The same process was repeated including second-trimester biometric parameters: biparietal diameter, head circumference, femur length and abdominal circumference in the regression models (Cust-plus-USS-chart). The association between small-for-gestational age < 10(th) centile (SGA) pregnancies, defined using the two customized charts or our population-based growth chart (Pop-chart) and IUFD, were compared. Statistical analyses including OR, 95% CI and screening accuracy using each chart were performed.

RESULTS

The derived coefficients for fetal growth are comparable to those of previously published series. Of 24 184 pregnancies in the validation sample, IUFD was seen in 169 (0.7%). The pregnancies identified as SGA were: 2482 (10.26%), 2499 (10.33%) and 2634 (10.89%) using the Cust-chart, Cust-plus-USS-chart and Pop-chart, respectively. The OR (95% CI) for the association between SGA defined by the three charts and IUFD was: 7.0 (4.5-11), 6.5 (4.2-10.2) and 2.4 (1.6-3.6) according to the Cust-chart, Cust-plus-USS-chart and Pop-chart, respectively. Screening efficiency for IUFD using both customized charts was similar, with both demonstrating a higher sensitivity compared with the Pop-chart.

CONCLUSIONS

Customized charts are more efficient in identifying pregnancies at risk for IUFD compared with population-based charts. However, adding second-trimester ultrasound biometric parameters to the customized model does not improve the prediction of IUFD compared with using maternal characteristics only.

Influence of chorionicity on perinatal outcome in a large cohort of Danish twin pregnancies

OBJECTIVE

To assess outcome in twin pregnancies according to chorionicity.

METHODS

A cohort was retrieved from local ultrasound databases at 14 obstetric departments in Denmark, comprising all twin pregnancies with two live fetuses scanned between weeks 11 and 14 in the period 1 January 2004 to 31 December 2006. Outcome data were retrieved from the National Board of Health.

RESULTS

Among 2038 twin pregnancies, 1757 (86.2%) were dichorionic (DC) and 281 (13.8%) were monochorionic diamniotic (MC). In MC pregnancies, the rate of spontaneous fetal loss in both second and third trimesters was more than threefold higher than the comparable rate in DC pregnancies: 6.0% vs. 1.9% for at least one fetus in the second trimester (P < 0.001) and 2.1% vs. 0.7% in the third trimester (P = 0.03). In 98.4% of DC pregnancies and in 91.1% of MC pregnancies, at least one infant was liveborn. Amongst pregnancies with two live fetuses at 24 weeks, the proportion with two live infants at 28 days after delivery was 97.5% and 95.1%, respectively.

CONCLUSIONS

The increased incidence of fetal loss in MC pregnancies compared with DC pregnancies predominantly occurs before 24 weeks' gestation. After this stage, although the risk of intrauterine fetal death is still higher in MC than in DC pregnancies, if both fetuses are alive at 24 weeks, the chance of a woman having two live infants 1 month after delivery is similar in MC and DC pregnancies.

Accuracy of first-trimester ultrasound in the diagnosis of early embryonic demise: a systematic review

OBJECTIVES

To evaluate, by systematic review of the literature, the accuracy of first-trimester ultrasound in diagnosing early embryonic demise.

METHODS

We searched MEDLINE (1951-2011), Embase (1980-2011) and the Cochrane Library (2010) for relevant citations. The reference lists of all known primary and review articles were examined. Language restrictions were not applied. Studies which evaluated the accuracy of first-trimester ultrasonography in pregnant women for the diagnosis of early embryonic demise were selected in a two-stage process and their data extracted by two reviewers. Accuracy measures including sensitivity, specificity and likelihood ratios (LRs) for abnormal and normal test results were calculated for each study and for each test threshold.

RESULTS

Eight primary articles with four test categories (18 2 × 2 tables), involving 872 women, evaluated the accuracy of ultrasound in diagnosing early embryonic demise. The lower limit of the 95% CI for specificity was > 0.95 in only two tests. These were an empty gestational sac with mean diameter of ≥ 25 mm and absent yolk sac with a mean gestational sac diameter of ≥ 20 mm (specificity, 1.00; 95% CI, 0.96-1.00 for both).

CONCLUSIONS

There is a paucity of high-quality, prospective data on which to base guidelines for the accurate diagnosis of early pregnancy demise. The findings are limited by the small number of studies and patients, the age of the studies, inclusion of symptomatic and asymptomatic women and variable reference standards for diagnosis of early pregnancy demise. Before guidelines for the safe management of threatened miscarriage can be formulated, there is an urgent need for an appropriately powered, prospective study using current ultrasound technology and an agreed reference standard for pregnancy success or loss.

Value of "minimum menstrual age" in determining early pregnancy failure

OBJECTIVES

The purposes of this study were to assess a discriminatory "minimum menstrual age" (28 days + number of days elapsed between the first positive pregnancy test result and sonogram) for the diagnosis of early pregnancy failure when no embryonic/fetal heartbeat is seen and to compare minimum menstrual age dating with last menstrual period and sonographic dating.

METHODS

We conducted a retrospective study of 338 initial first-trimester sonographic examinations among women with suspected early pregnancy failure. A minimum menstrual age for each was calculated, and pregnancy outcomes were assessed. The predictive value of the minimum menstrual age for the pregnancy outcome was assessed at both 42 and 49 days and compared to that of dating by the last menstrual period and sonography.

RESULTS

Among a study cohort of 338 patients, the average gestational age calculated by the last menstrual period was 53 days; by sonography, it was 50 days; and by the minimum menstrual age, it was 35 days (P < .01). All cases in which there was no sonographically detectable embryonic heartbeat above a minimum menstrual age of 42 days resulted in pregnancy failure.

CONCLUSIONS

The minimum menstrual age is a conservative estimate of the gestational age, with an estimated positive predictive value of 100% for early pregnancy failure when no embryonic heartbeat is seen after 42 days. The minimum menstrual age can be combined with other existing diagnostic clues to predict early pregnancy failure with greater accuracy.

[Fetal acardia in a twin pregnancy achieved by in vitro fertilization]

The frequency of fetal arcadia in the world is 1:35,000 to 1:48,000 pregnancies; is currently estimated that 1% of newborns in developed countries are the result of assisted reproduction techniques and the frequency of twin pregnancies is close to 18%, of these, an estimated relative risk for cardiac defect is 1.6. However, the association of acardiac fetus, twin pregnancy and assisted reproductive techniques is not fully established. In this paper, we describe a case of fetal acardia, in a pregnancy resulting from assisted reproduction and its obstetric care.

Conjoined twins in a spontaneous trichorionic quadruplet pregnancy: a case report

BACKGROUND

Multifetal pregnancies are high-risk pregnancies. Coexistence of conjoint twins with multifetal pregnancies further increases the risk factor, which is already considerably high with multiple births. Assisted reproductive techniques lead to an increase in multifetal pregnancies, especially monozygotic pregnancies, which in turn lead to an increase in the rate of conjoined twins.

CASE

A spontaneously achieved quadruplet pregnancy with coexisting conjoint twins has not been reported previously. We report one such case of spontaneously achieved quadruplet pregnancy with coexisting conjoined twins.

CONCLUSION

Early (preferably first trimester) recognition of multifetal pregnancy, chorionicity, amnionicity and fetal malformation help in proper pregnancy management and optimizing outcome.

[Fetus compressus and fetus papyraceous. Clinical differences (report of three cases)]

The items papyraceus fetus and fetus compressus are used like synonymous. The low incidence and the lack of reporting of these cases leads to confusion. Clinical evidence shows significant differences between them and sustain a proper diagnosis. We report 3 cases of patients with multiple pregnancy (2 twins and 1 triplets) observed in the death of one of the products of each patient, obtaining 2 fetus compressus and 1 fetus papyraceous, respectively.

Assessment of fetal well-being in cattle by ultrasonography in normal, high-risk, and cloned pregnancies

This study determined ultrasonographic parameters of fetuses and uterine adnexa in late pregnancy in normal, cloned, and high-risk pregnancies in relation to perinatal and neonatal outcome. Ten cows with normal pregnancies (CONTROL, mean pregnancy length 273 d), 10 sick cows with potentially compromised pregnancies (HIGH-RISK, mean pregnancy length 267 d), and 10 heifers with cloned pregnancies (CLONED, mean pregnancy length 274 d) were examined at more than 260 d of gestation. There was no difference in mean fetal heart rates among the groups. The cloned calves were heavier (57 ± 8 kg) than calves from CONTROL group (36 ± 7 kg), and calves from HIGH-RISK group (37 ± 13 kg) (P = 0.003). The diameter of the thoracic aorta was positively correlated (R = 0.62) with fetal birth weight in the CONTROL group (P = 0.01). Fetal activity was not associated with survival. The results suggest that transabdominal ultrasonographic assessment of the fetal well-being may serve as a potential tool for evaluation of the fetoplacental unit.

Doppler assessment between pathological examination of the placenta and late fetal intrauterine demise

AIM

The relation between placental histopathological examination, umbilical cord pathology and abnormal umbilical and cerebral Doppler as a predictor of stillbirth at later gestations was evaluated.

MATERIALS AND METHODS

A retrospective study of 55 monofetal pregnancies complicated with late fetal death from 2005-2008 was conducted at the Institute of Gynecology and Obstetrics, Bel-grade.

STATISTICAL ANALYSIS

chi-square likelihood ratio test and Spearman's coefficient correlation.

RESULTS

Intrauterine fetal demise occurred most frequently at term -32.7% of the time. Changes in the umbilical artery resistance index were not significantly different from placental histopathology findings, p = 0.363. There was a significant correlation between neonatal birth weight and weeks of gestation at delivery, r = 0.796; p = 0.001.

CONCLUSION

Umbilical artery Doppler is a relatively poor predictor of stillbirths due to placental dysfunction. It seems that neonatal birth weight is the best predictor of late stillbirth in high-risk pregnancies.

Ultrasound predictors of mortality in monochorionic twins with selective intrauterine growth restriction

OBJECTIVES

The aim of this study was to evaluate the use of ultrasound assessment to predict risk of mortality in expectantly managed monochorionic twin fetuses with selective intrauterine growth restriction (sIUGR).

METHODS

This was a retrospective study of 101 monochorionic twin pregnancies diagnosed with sIUGR before 26 weeks of gestation. All patients were under expectant management during the observation period. At the initial evaluation, the presence or absence of each of the following abnormalities was documented: oligohydramnios; stuck twin phenomenon; severe IUGR < 3(rd) centile of estimated fetal weight; abnormal Doppler in the umbilical artery; and polyhydramnios in the larger twin. The relationships between these ultrasound findings and mortality of sIUGR fetuses were evaluated using multiple logistic regression analysis.

RESULTS

Of 101 sIUGR twins, 22 (21.8%) fetuses suffered intrauterine demise and nine (8.9%) suffered neonatal death; 70 (69.3%) survived the neonatal period. Multiple logistic regression analysis revealed that the stuck twin phenomenon (odds ratio (OR): 14.5; 95% CI: 2.2-93.2; P = 0.006) and constantly absent diastolic flow in the umbilical artery (OR: 29.4; 95% CI: 3.3-264.0; P = 0.003) were significant risk factors for mortality.

CONCLUSIONS

Not only abnormal Doppler flow in the umbilical artery but also severe oligohydramnios should be recognized as important indicators for mortality in monochorionic twins with sIUGR.

Structural anomalies in early embryonic death: a 3-dimensional pictorial essay

OBJECTIVE

The purpose of this pictorial essay was to determine whether 3-dimensional (3D) surface rendering of a dead first-trimester embryo can provide any information for the loss.

METHODS

Three-dimensional surface rendering was performed on a collection of dead first-trimester embryos with crown-rump lengths between 12 and 27 mm. These were compared with 2-dimensional (2D) images of the same embryos and with 2D images and 3D surface renderings of normally developing embryos.

RESULTS

Surface rendering of dead embryos showed a variety of abnormalities in the contour and limb formation.

CONCLUSIONS

The use of 3D sonography may provide insight into the etiology of first-trimester embryonic death.

Cord entanglement and perinatal outcome in monoamniotic twin pregnancies

OBJECTIVES

To assess the prevalence of cord entanglement and perinatal outcome in a large series of monoamniotic twin pregnancies and to review the recent literature on similar published large series.

METHODS

Prospective observational study of all prenatally detected cases of monoamniotic twin pregnancies during an 8-year period in a tertiary fetal medicine unit. A Medline database review for publications since 2000 containing five or more cases of monoamniotic pregnancies that showed data on cord entanglement and perinatal outcome was also undertaken.

RESULTS

A total of 32 monoamniotic pregnancies were diagnosed during the study period, including three conjoined twins, seven pregnancies with twin reversed arterial perfusion (TRAP) syndrome, three surgical pregnancy interruptions for discordant fetal abnormality and one miscarriage before 16 weeks' gestation. The remaining 18 monoamniotic pregnancies were included in the study analysis. All monoamniotic pregnancies were complicated with antenatal cord entanglement diagnosed by B-mode and color Doppler ultrasound. There were 34 live births and a double intrauterine death diagnosed at 19 + 2 weeks' gestation. There were two late neonatal deaths, one from congenital complete heart block and the other after surgery for transposition of the great arteries. The overall perinatal loss rate was 11.1% after 16 weeks and 5.9% after 20 weeks' gestation. The cumulative rates of cord entanglement and perinatal mortality in the reviewed literature were 74% and 21%, respectively.

CONCLUSIONS

Umbilical cord entanglement is present in all monoamniotic twins when it is systematically evaluated by ultrasound and color Doppler. Perinatal mortality in monoamniotic twins is mainly a consequence of conjoined twins, TRAP, discordant anomaly and spontaneous miscarriage before 20 weeks' gestation. Expectantly managed monoamniotic twins after 20 weeks have a very good prognosis despite the finding of cord entanglement. The practice of elective very preterm delivery or other interventions to prevent cord accidents in monoamniotic twins should be re-evaluated.

The yolk stalk sign: evidence of death in small embryos without heartbeats

OBJECTIVE

The purpose of this study was to assess the positive predictive value for confirming early embryonic death in the clinical sonographic scenario wherein an embryo is identified without a visible heartbeat; the embryonic crown-rump length (CRL) is 5 mm or less; and the embryo is not immediately adjacent to the yolk sac.

METHODS

A retrospective study of 882 first-trimester sonograms was performed among women who had an intrauterine pregnancy of uncertain viability based on 1 or more sonographic findings (eg, no visible heartbeat in an embryo with a CRL of < or =5 mm). Eight hundred six cases met the inclusion criteria.

RESULTS

Among the cohort of 806 cases, 520 (64.5%) had an identifiable embryo. One hundred fifty-nine of these embryos had no demonstrable heartbeat and a CRL of 5 mm or less. The CRLs of these embryos ranged from 1.7 to 5.4 mm. This cohort's sonograms were reviewed to determine whether there was a separation between the embryo and yolk sac. Twenty-one cases were discovered. Recall that as a retrospective study, no specific effort was made to show this finding. Thus, a computation of the sensitivity of this finding would result in an underestimate of indeterminate magnitude. All of these cases were subsequently proven to be failed pregnancies.

CONCLUSIONS

The positive predictive value of the "yolk stalk sign" in determining early pregnancy failure for an embryo with a CRL of 5 mm or less and no visible heartbeat was 100% in this cohort.

Prevalence and perinatal outcome of dichorionic and monochorionic twins with nuchal translucency above the 99(th) percentile and normal karyotype

OBJECTIVE

To evaluate the prevalence of and perinatal outcome associated with increased nuchal translucency thickness (NT) > 99(th) percentile in dichorionic and monochorionic twins with normal karyotype.

METHODS

Two hundred and six consecutive twin pregnancies (166 dichorionic and 40 monochorionic) underwent an NT scan during a 4-year period. In those with NT > 99(th) percentile and normal karyotype, we performed first- and second-trimester anomaly scans, fetal echocardiography at 14-16 and 20-22 weeks, maternal serology and, in monochorionic pregnancies, serial ultrasound examinations every other week. Perinatal outcome was recorded.

RESULTS

There were 10 (4.95%) pregnancies in which one of the fetuses had NT > 99(th) percentile and normal karyotype, including five fetuses (1.5%) in dichorionic and five (6.25%) in monochorionic pregnancies. During the same period the prevalence of NT > 99(th) percentile and normal karyotype in singleton pregnancies studied in our center was 2.6%. Among the 10 twins affected, six (60%) were diagnosed with structural abnormalities (three dichorionic and three monochorionic), and two intrauterine fetal demises occurred (one dichorionic and one monochorionic). Thus, the perinatal outcome was normal in only two of the pregnancies, one dichorionic and one monochorionic.

CONCLUSIONS

The prevalence of NT > 99(th) percentile in dichorionic twins with a normal karyotype is similar to that in singletons. In monochorionic twins we confirmed previous studies reporting an increased prevalence compared with singletons. NT > 99(th) percentile with a normal karyotype in twins was associated with a high rate of fetal abnormalities and/or fetal demise (overall 80%) irrespective of chorionicity.

Prenatal diagnosis of idiopathic infantile arterial calcification with hydrops fetalis

Idiopathic infantile arterial calcification (IIAC) is a rare and nearly always fatal disorder. To date, prenatal diagnosis has been reported in fewer than 10 cases. We describe a series of three cases in which the diagnosis of IIAC was made at 23, 25 and 29 weeks' gestation. All three cases presented with a normal anatomy scan at 20 weeks' gestation with an echogenic intracardiac focus. Follow-up scans showed generalized hyperechogenicity and calcification of the walls of the large arteries, particularly the aorta and the iliac arteries. All cases developed hydrops fetalis with cardiomegaly and polyhydramnios later in gestation, resulting in intrauterine fetal death in two cases and neonatal death immediately following delivery in the third. This is the largest case series and the earliest gestational age of prenatal diagnosis of IIAC reported to date. When surveying for the disease, serial scans are important, perhaps from 20 weeks' gestation, with close examination of the iliac and aortic arteries. Detection of echogenic intracardiac focus could be an early marker in patients with a family history of the disease.

Relationship of intertwin crown-rump length discrepancy to chorionicity, fetal demise and birth-weight discordance

OBJECTIVES

To study the frequency and clinical significance of crown-rump length (CRL) discrepancy at 11-14 weeks of gestation in twin pregnancies from an unselected population.

METHODS

This was a retrospective analysis of all twin pregnancies that underwent a routine 11-14-week scan at a large teaching hospital. Fetal loss was defined as fetal demise of one or both twins after 14 weeks.

RESULTS

A total of 507 twin pregnancies were studied; 382 (75.3%) were dichorionic and 125 (24.7%) were monochorionic twins. The discrepancy in CRL was expressed as a percentage of the CRL of the larger twin. The 95(th) and 99(th) centile for CRL discrepancy in twins was 12.2% and 19.3%, respectively. The discrepancy in CRLs in monochorionic and dichorionic twins was not significantly different (Mann-Whitney U = 22,406, P = 0.302). In 39 twin pairs, there was subsequent intrauterine death of one or both twins. Fetal loss was more common in monochorionic twins (24/125) than in dichorionic twins (15/382) (chi-square = 30.9, P < 0.001). In monochorionic twins, the discrepancy in CRLs in the 24 cases with subsequent loss was significantly greater than in the 101 twin pairs with no subsequent loss (Mann-Whitney U = 896, P = 0.048). The discrepancy in CRLs in 15 dichorionic twins with subsequent loss was not different from that in the 367 twins with no loss (Mann-Whitney U = 2116.5, P = 0.129). The CRL discrepancy was significantly correlated with birth-weight discordance in twins (Spearman's rho = 0.128, P = 0.006). However, this was due to a significant correlation in dichorionic twins (Spearman's rho = 0.127, P = 0.016) but not in monochorionic twins (Spearman's rho = 0.145, P = 0.14).

CONCLUSIONS

Fetal loss is significantly associated with discrepancy in CRL at the 11-14-week scan in monochorionic twins and discordance in birth weights is significantly associated with discrepancy in CRL in dichorionic twins. However, intertwin CRL discrepancy is of limited value in screening for these adverse events.

The effect of anticoagulation on antenatal ultrasound findings in pregnant women with thrombophilia

OBJECTIVE

To assess whether treatment with heparin alters ultrasound findings in pregnant women with inherited thrombophilia.

METHODS

This was a retrospective study of a cohort of patients referred for pregnancy complications who were found to have genetic thrombophilia. Ultrasounds were reviewed in treated and untreated pregnancies for the presence of growth restriction, oligohydramnios or abnormal Doppler results.

RESULTS

There were a total of 178 pregnancies in 51 patients. The overall percentage of abnormal ultrasounds was significantly greater in the untreated compared with treated pregnancies (52.8% vs. 27.9%; p = 0.024.) Growth restriction and abnormal Doppler results were more common in untreated pregnancies. There was a significantly decreased risk of oligohydramnios with treatment (27.3% vs. 7%; p = 0.03). Overall outcomes were significantly improved with the use of anticoagulation ( p < 0.0001).

CONCLUSIONS

Treatment markedly improves ultrasound parameters of growth, fluid and feto-placental blood flow in patients with thrombophilia. The presence of abnormalities despite treatment reinforces the need for close antenatal surveillance.

Twin pregnancy with fetus papyraceous

A successful pregnancy outcome with vaginal delivery of a term single live fetus in case of twin pregnancy with other twin papyraceous, (vanished in second trimester) is an uncommon finding. Ten percent of all perinatal deaths are related with dizygotic twins. The rate of intrauterine fetal demise in multiple pregnancies is as high as three times of monozygotic. Most frequently used and suggested method is follow-up of the maternal coagulation system by a series of lab test. Sonography is a visual tool to confirm the diagnosis. In case of monofetal death of twin pregnancies, the type of placenta should be analysed and then follow up and treatment modalities of these cases should be choosen.

Ultrasonographic fetal well-being assessment, neonatal and postpartum findings of cloned pregnancies in cattle: a preliminary study on 10 fetuses and calves

Cloned pregnancies in cattle are considered to be at risk due to a variety of fetal or adnexal abnormalities. Data is lacking concerning the possibility of transabdominal ultrasonography in the assessment of these high risk pregnancies. Transabdominal ultrasonography has rarely been reported in the assessment of bovine cloned pregnancies. Ten Holstein heifers carrying 8-month-old cloned fetuses were assessed by transabdominal ultrasonographic examination during the 3rd trimester of pregnancy. Fetal heart rates (FHR), movements, adnexal appearance, and placentome size were recorded. The outcome of the pregnancies was also noted and potential indicators of fetal demise recorded. Survival rate 1 week after birth was 30%. Mean FHR was 113 beats per minute (range: 92 to 128 bpm) during the fetal ultrasonography. No correlation between FHR and fetal activity was found. Fetal hyperactivity and imaging of hyperechoic particles in both allantoic and amniotic fluids were possible signs of fetal distress. Despite the size of the fetus and the deep bovine abdomen, fetal transabdominal ultrasonography can be performed in cattle. This preliminary study points to the necessity of further larger studies for defining normal and abnormal findings in bovine late pregnancy.

Five-millimeter and smaller embryos without embryonic cardiac activity: outcomes in women with vaginal bleeding

OBJECTIVE

The purpose of this study was to assess outcomes in embryos with a crown-rump length (CRL) of 5 mm or less without embryonic cardiac activity (ECA) among pregnant women with vaginal bleeding in the first trimester.

METHODS

A retrospective study of all first-trimester sonograms in women with vaginal bleeding from 1999 to 2002 was conducted.

RESULTS

Thirty-seven embryos without detectable ECA that had a CRL of 5 mm or less were identified. All resulted in pregnancy failure. The breakdown of these embryos by CRL was as follows: 13 were 5 mm; 10 ranged from 4 to 4.9 mm; 11 ranged from 3 to 3.9 mm; and 3 ranged from 2 to 2.9 mm.

CONCLUSIONS

In pregnant women with vaginal bleeding, embryos of 5 mm and smaller without a heartbeat all resulted in pregnancy failure.

Color Doppler twinkling artifact in intrauterine fetal demise

PURPOSE

To determine whether twinkling artifacts on color and power Doppler sonography could be used as a new sonographic sign of intrauterine fetal demise (IUFD).

METHODS

In this prospective study, 24 consecutive pregnant women with IUFD were included after fetal sonographic examinations. Sonographic examination included gray-scale, color, power, and spectral Doppler imaging. The sonograms were then analyzed for the presence, appearance, and intensity of the twinkling artifacts.

RESULTS

Twinkling artifacts on color Doppler were observed in all of the 24 IUFD as a rapidly changing color Doppler signal complex associated persistently with different parts of the fetal body. The artifacts were localized especially in the neck, back, and iliac regions. Artifact intensity correlated with the time elapsed since death.

CONCLUSION

Twinkling artifact was noted in all dead fetuses on color, power, and spectral Doppler examinations. Thus, the observation of these artifacts may be considered as a new sonographic sign of fetal demise, which may reflect the time elapsed since death.

Nuchal translucency thickness in monochorionic multiple pregnancies: value in predicting pregnancy outcome

OBJECTIVES

The purpose of this study was to investigate the value of first-trimester nuchal translucency (NT) thickness in predicting the pregnancy outcome in monochorionic multiple pregnancies.

METHODS

Thirty monochorionic multiple pregnancies were evaluated for NT thickness at a median gestational age of 12 weeks (range, 11-14 weeks). Information on pregnancy outcome was obtained from all cases. A poor pregnancy outcome was defined as fetal death or miscarriage before 24 weeks, development of twin-twin transfusion syndrome (TTTS), or preterm delivery before 32 weeks.

RESULTS

The NT thickness was above the 95th percentile for gestational age in at least 1 fetus in 5 (17%) pregnancies, and a poor pregnancy outcome was recorded in 14 (47%) pregnancies. The overall sensitivity was 36% (5/14); specificity, 100% (16/16); positive predictive value, 100% (5/5); and negative predictive value, 64% (16/25). In pregnancies with increased compared with normal NT thickness, no significant correlation was found with the subsequent development of TTTS (1/5 [20%] versus 5/25 [20%]) and miscarriage or fetal death before 24 weeks (1/5 [20%] versus 3/25 [12%]). However, among the 20 pregnancies not complicated by TTTS or loss before 24 weeks, there was a significantly increased rate of delivery before 32 weeks in the former group (3/4 [75%] versus 1/16 [6.3%]; P = .01).

CONCLUSIONS

In monochorionic multiple pregnancies, an increased NT thickness measurement had a high specificity and positive predictive value for adverse perinatal outcomes. However, the sensitivity and negative predictive value were low, with a normal NT thickness measurement poorly predicting development of complications; therefore, close sonographic follow-up should be carried out in all cases, irrespective of NT thickness.

Relationship between crown-rump length and early detection of cardiac activity

OBJECTIVE

To investigate whether improvements in sonographic technology would allow detection of embryonic demise at a crown-rump length (CRL) < 5 mm.

STUDY DESIGN

A prospectively collected, computerized ultrasound database was queried for singleton gestations with CRL < or = 5 mm from January 2000 to February 2003. Embryonic viability was determined by repeat ultrasound examination after 6 weeks'gestation confirming cardiac activity or by documentation of an ongoing pregnancy. Viability rates in the presence or absence of cardiac activity were calculated for CRL of 2.0-2.9, 3.0-3.4, 3.5-3.9, 4.0-4.4, 4.5-4.9 and 5.0 mm. Sensitivity, specificity, positive predictive value and negative predictive value for embryonic demise were calculated, with a subanalysis based on the presence of vaginal bleeding.

RESULTS

Outcome was available for 179 of 195 gestations meeting inclusion criteria. The absence of cardiac activity at CRL > or = 3.5 mm had 100% positive predictive value and specificity. The presence of vaginal bleeding did not affect this cutoff.

CONCLUSION

Improved sonographic technology permits diagnosis of embryonic demise at a CRL > or = 3.5 mm under ideal conditions. Vaginal bleeding increases the likelihood of demise, but does not alter test performance. Further investigation is warranted, as our data suggest a limit closer to 3 mm.

Discordance in nuchal translucency thickness in the prediction of severe twin-to-twin transfusion syndrome

OBJECTIVE

To examine in monochorionic pregnancies the possible value of intertwin discordance in nuchal translucency (NT) thickness in the prediction of early fetal death or severe twin-twin transfusion syndrome (TTTS).

METHODS

In 512 monochorionic twin pregnancies NT was measured at 11 to 13 + 6 weeks' gestation and regression analysis was used to determine the significance of the association between the intertwin discordance in NT and subsequent early fetal death or development of severe TTTS requiring endoscopic laser surgery.

RESULTS

In 412 (80.5%) pregnancies there was a normal outcome, in 58 (11.3%) there was severe TTTS requiring endoscopic laser surgery at 18-24 weeks, in 19 (3.7%) there was death of one or both fetuses at 13-18 weeks and in 23 (4.5%) there was fetal death at 21-38 weeks. In the four outcome groups the median discordance in NT was 11%, 22%, 35% and 7%, respectively. Significant prediction of early fetal death and severe TTTS was provided by the discordance in fetal NT, which was not significantly improved by including the discordance in crown-rump length. If the discordance in NT was 20% or more, the false positive rate was 20%, the detection rate of early fetal death was 63% and the detection rate of severe TTTS was 52%.

CONCLUSIONS

Discordance in NT of 20% or more is found in about 25% of monochorionic twins and in this group the risk of early fetal death or development of severe TTTS is more than 30%. If the discordance is less than 20% the risk of complications is less than 10%.

[Intrauterine intestinal volvulus and fetus compressus papyraceus in twins]

Intrauterine intestinal volvulus and fetus compressus papyraceus in twins. In a double twin pregnancy revealed on the 16th gestation week by ultrasound examination, a foetus papyraceus was detected on the 20th gestation week in a 29 year old woman. On the 32nd gestational week two monochorionic-diamniotic male stillborn twins were born. One of them (15 cm/35 g) was rudimentary developed and compressed. On examination of the other (39 cm/1485 g) partially macerated foetus, volvulus of small intestine with hemorrhagic necrosis was found at the autopsy. Both of the anomalies are very rare.

[Umbilical cord entanglement in monoamniotic twin preganacy--case presentation and literature review]

Monoamniotic twins are at most increased risk of perinatal complications with perinatal mortality of 28-60 % reported in literature. The most specific complication to monoamniotic twins is entanglement and (or) knotting of the cords leading to intrauterine death of both (more often) or one twin. In first presented case 1, 23-year-old primigravida in 33wks of twin monoamniotic gestation was reffered to our Institute due to intrauterine death of one co-twin caused by umbilical cord entanglement. In second case, 26-year-old multigravida in monoamniotic twin gestation was admitted to our institution. A serious umbilical cord entanglement was observed and a presence of true knot of umbilical cord was suspected. Presented cases indicate that establishing a chorionicity and amniocity in twin pregnancy is an essential part of ultrasound examination. The diagnosis of cord entanglement in monoamniotic twin pregnancy enables a forecasting of possible complications. According to the established diagnosis future protocols of perinatal management could be proposed. Due to possible complications counseling and management of monoamniotic twins should be performed in tertiary medical centers.

Medical treatment for early fetal death (less than 24 weeks)

BACKGROUND

In most pregnancies that miscarry, arrest of embryonic or fetal development occurs some time (often weeks) before the miscarriage occurs. Ultrasound examination can reveal abnormal findings during this phase by demonstrating anembryonic pregnancies or embryonic or fetal death. Treatment before 14 weeks has traditionally been surgical but medical treatments may be effective, safe, and acceptable, as may be waiting for spontaneous miscarriage.

OBJECTIVES

To assess the effectiveness, safety and acceptability of any medical treatment for early pregnancy failure (anembryonic pregnancies or embryonic and fetal deaths before 24 weeks).

SEARCH STRATEGY

We searched the Cochrane Pregnancy and Childbirth Group Trials Register (30 November 2005).

SELECTION CRITERIA

Randomised trials comparing medical treatment with another treatment (e.g. surgical evacuation), or placebo, or no treatment for early pregnancy failure. Quasi-random studies were excluded.

DATA COLLECTION AND ANALYSIS

Data were extracted unblinded.

MAIN RESULTS

Twenty four studies (1888 women) were included. Vaginal misoprostol hastens miscarriage (complete or incomplete) when compared with placebo: e.g. miscarriage less than 24 hours (two trials, 138 women, relative risk (RR) 4.73, 95% confidence interval (CI) 2.70 to 8.28), with less need for uterine curettage (two trials, 104 women, RR 0.40, 95% CI 0.26 to 0.60) and no significant increase in nausea or diarrhoea. Lower-dose regimens of vaginal misoprostol tend to be less effective in producing miscarriage (three trials, 247 women, RR 0.85, 95% CI 0.72 to 1.00) with similar incidence of nausea. There seems no clear advantage to administering a 'wet' preparation of vaginal misoprostol or of adding methotrexate, or of using laminaria tents after 14 weeks. Vaginal misoprostol is more effective than vaginal prostaglandin E in avoiding surgical evacuation. Oral misoprostol was less effective than vaginal misoprostol in producing complete miscarriage (two trials, 218 women, RR 0.90, 95% CI 0.82 to 0.99). Sublingual misoprostol had equivalent efficacy to vaginal misoprostol in inducing complete miscarriage but was associated with more frequent diarrhoea. The two trials of mifepristone treatment generated conflicting results. There was no statistically significant difference between vaginal misoprostol and gemeprost in the induction of miscarriage for fetal death after 13 weeks.

AUTHORS' CONCLUSIONS

Available evidence from randomised trials supports the use of vaginal misoprostol as a medical treatment to terminate non-viable pregnancies before 24 weeks. Further research is required to assess effectiveness and safety, optimal route of administration and dose. Conflicting findings about the value of mifepristone need to be resolved by additional study.

Perinatal outcome associated with sonographically detected globular placenta

OBJECTIVE

To evaluate the association between the sonographic appearance of globular placenta and perinatal outcome.

STUDY DESIGN

We prospectively followed the pregnancy course and perinatal outcome in women with globular placentas (hyperechoic, thick and highly vascular placentas with edges that lack the typical "tapering" appearance) during routine sonographic study.

RESULTS

Fourteen women were included. In 7 women the globular appearance of the placenta normalized spontaneously, and perinatal outcome was good. The other 7 experienced poor perinatal outcomes. There were no significant differences between the 2 groups. Among pregnancies in which the globular placental appearance persisted, 3 resulted in fetal demise; 3 women had severe intrauterine growth restriction and oligohydramnios and underwent cesarean deliveries at 26, 27 and 31 weeks, respectively; and 1 patient had premature preterm rupture of membranes and underwent a cesarean delivery due to placental abruption.

CONCLUSION

In half the pregnancies complicated by the sonographic appearance of a globular placenta, this shape spontaneously normalized, and the perinatal outcome was normal. However, when the globular appearance of the placenta persisted, the condition was associated with a poor perinatal outcome. Pregnancies complicated by a globular placenta should be followed closely.

Is Small for Gestational Age a Marker of Future Fetal Survival In Utero?

OBJECTIVE

We sought to assess whether small for gestational age is a risk factor for stillbirth of a subsequent sibling.

METHODS

The Missouri maternally linked cohort data set, containing data on births from 1978 through 1997, was used. We identified the study group (women who delivered a SGA infant in the first pregnancy) and a comparison group (women who delivered a non-SGA infant in their first pregnancy) and compared the outcome (stillbirth) in the second pregnancy between both groups.

RESULTS

We analyzed information on the first and second pregnancies of 402,015 women (43,549 [10.8%] in the study arm and 358,466 [89.2%] in the comparison arm). Of the 1,883 cases of stillbirth in the second pregnancy, 314 cases occurred in mothers with a history of SGA (stillbirth rate 7.2/1,000) and 1,569 in the comparison group (stillbirth rate 4.4/1,000), P < .001. The adjusted risk of stillbirth was 60% higher in women with a prior SGA (odds ratio [OR] 1.6, 95% confidence interval [CI] 1.4-1.8). The risk for stillbirth in the second pregnancy increased with decreasing gestational age at birth of the SGA infant in the first pregnancy (term: OR 1.4, 95% CI 1.2-1.6; preterm: OR 2.8, 95% CI 2.0-3.8; and very preterm: OR 4.2, 95% CI 2.4-7.3), P for trend < .001.

CONCLUSION

Small for gestational age is a marker for subsequent stillbirth, and the risk rises with decreasing gestational age of the SGA birth. This information is potentially useful for counseling parents of SGA infants.

LEVEL OF EVIDENCE

II-2.

Relationship between heat stress during the peri-implantation period and early fetal loss in dairy cattle

The aim of the present study was to establish whether temperature-humidity index values, as a measure of heat comfort, from Days 1 to 40 of gestation could be associated with the pregnancy loss rate in high producing dairy cows. Data from 1391 pregnancies were recorded. Pregnancy was diagnosed by transrectal ultrasonography between Days 34 and 45, and again 90 days after insemination. Pregnancy loss was assumed when the second pregnancy diagnosis on Day 90 proved negative and was registered in 7.8% (108/1391) of pregnancies. Mean and maximum temperature-humidity index values were established for each cow for Days 0 (day of insemination), 1, 2 and 3 after insemination, and averages established for Days 0-3, 0-10, 11-20, 21-30 and 31-40 after insemination. Cow and management variables previously found to be significantly correlated with the early fetal loss in the same geographical area were also recorded. The relative contribution of each factor to the probability of pregnancy loss was determined using logistic regression models. Based on the odds ratio, a strong association with pregnancy loss of the factors warm period of pregnancy (warm period-May to September versus cool-October to April), twin pregnancy (as negative factors: odds ratios 3.1 and 3.4, respectively) and an additional corpus luteum (as a positive factor: odds ratio 0.32) was confirmed. The likelihood of pregnancy loss increased by a factor of 1.05 for each additional unit of the mean maximum temperature-humidity index from Days 21 to 30 of gestation. Logistic regression analysis revealed no significant effects of temperature-humidity index values for the remaining gestation periods. Our results indicate that heat stress can compromise the success of gestation during the peri-implantation period, such that high temperature-humidity index values for the period 21-30 days of gestation are a risk factor for subsequent early fetal loss.

Radiography following perinatal death: a review

Radiography of the perinatally dead infant provides detailed information about the skeleton and is valuable as an adjunct to autopsy. This article reviews the potential benefits and discusses the pitfalls in assessment of growth stage. Reference charts for individual bone lengths and secondary ossification centers are presented.

Wernicke's encephalopathy: beyond alcoholism

BACKGROUND

A 17-year-old pregnant woman presented to hospital at 19 weeks' gestation with an 8-week history of hyperemesis gravidarum, 16.8 kg of weight loss, and new-onset weakness, dizziness and blurred vision. Examination of the patient showed confusion, papilledema, ophthalmoparesis, nystagmus, reduced hearing and truncal ataxia.

INVESTIGATIONS

Physical examination, abdominal ultrasound, fetal ultrasound, brain MRI, magnetic resonance angiography, magnetic resonance venography and cerebrospinal-fluid analysis.

DIAGNOSIS

Wernicke's encephalopathy, hyperemesis gravidarum and fetal loss.

MANAGEMENT

Intravenous thiamine repletion and elimination of deficiency risk factors.

Termination of second trimester, complicated gestation

To assess the effectiveness of intravaginal misoprostol for second trimester uterine evacuation, we studied 70 women with singleton pregnancies complicated by fetal malformation or dead fetuses. Participants received 200 microg misoprostol administered at 4-hour intervals. Gestations with dead fetuses had a shorter induction-abortion interval [14.2 hours, standard deviation (SD) 4.3] than those with live, malformed fetuses (20.2 hours, SD 7.3) (P< 0.001). The abortion rate was significantly higher for gestations with dead fetuses (92.1%) than those with live, malformed fetuses (68.8%) (P< 0.05). There were no major complications and no significant difference in the incidence of side-effects. All women aborted within 38 hours. Administration of misoprostol is an effective clinical method to terminate second trimester, complicated pregnancy.

Prenatal diagnosis and obstetric outcomes in triplet pregnancies in relation to chorionicity

OBJECTIVE

This study describes the frequency, pregnancy complications and outcomes of non-trichorionic triplet pregnancies.

DESIGN

A retrospective observational study.

SETTING

Two tertiary level referral centres of Obstetrics and Prenatal Medicine, Germany.

POPULATION

All women booked to receive targeted ultrasound screening between January 1998 and June 2003. The mixed low and high risk population included 36,430 women with ultrasound examinations between 11 and 24 weeks of gestation. Of those with available outcome, 176 were triplet pregnancies with three viable fetuses.

METHODS

Analysis of ultrasound data and perinatal outcome in triplet gestations who had first and second trimester targeted ultrasound examination. Pregnancies with monochorionic or dichorionic placentation were identified and pregnancy outcome was compared to trichorionic triplets.

MAIN OUTCOME MEASURES

Intrauterine fetal death, fetal growth restriction (FGR), mean discordance and survival rate in non-trichorionic versus trichorionic triplets.

RESULTS

Triplets were trichorionic in 81.8% and had a monochorionic or dichorionic placentation in the remaining 18.2%. The rate of monochorionicity and dichorionicity was significantly higher after spontaneous conception than after assisted reproductive technologies (44.8%vs 12.9%, P < 0.001). In non-reduced monochorionic and dichorionic triplets compared with non-reduced trichorionic triplets, there was a higher rate of intrauterine fetal death (8.8%vs 1.5%, P < 0.01), FGR (33.3%vs 25.5%), mean discordance (20.5%vs 12.7%, P < 0.01), discordance >30% (26.3%vs 2.9%, P < 0.01) and delivery <32 weeks of gestations (47.4%vs 32.2%). There was a lower survival rate in non-trichorionic triplets (84.2%) than in trichorionic ones (91.7%).

CONCLUSION

Triplet pregnancies with a monochorionic or dichorionic placentation are at significantly higher risk of adverse pregnancy outcome compared with trichorionic pregnancies. First trimester evaluation of chorionicity is strongly emphasised.

Fetal mortality diagnosis by ultrasound in the vicuña (Vicugna vicugna)

Ultrasonography is widely used in domestic species of camelids, but there is no information about the use of this technique for pregnancy diagnosis and determination of embryonic or fetal losses in the vicuña (Vicugna vicugna). The study was performed in 202 vicuñas (3-year-old females, n = 31; adult females, n = 171) mated during the summer months (January through March 2001) at the Abra Pampa Experimental Farm of Altitude in north-west Argentina. Transrectal ultrasound examination was performed in May (estimated 40-120 days of gestation) to determine the number of pregnant females. The pregnancy rate was 45.5% (92/202). No significant difference (P > 0.05) was observed between the pregnancy rate of 3-year-old females (41.9%) and adult females (46.2%). In December (estimated 250-330 days of gestation) of the same year, a second ultrasonographic study was performed on those vicuñas that were diagnosed as pregnant from the first ultrasound scan. Of 92 animals diagnosed as pregnant in May, only 84 were present in December, because eight females died in the period of study. Overall, 11.9% (10/84) of fetuses were lost during the period (18.1% in 3-year-old vicuñas and 10.9% in adult vicuñas). In conclusion, transrectal ultrasonography was found to provide a rapid and non-invasive means for pregnancy and fetal mortality diagnosis in vicuñas.

Spontaneous reduction of advanced twin embryos: its occurrence and clinical relevance in dairy cattle

Twin pregnancies represent a management problem in dairy cattle since the risk of pregnancy loss increases, and the profitability of the herd diminishes drastically as the frequency of twin births increases. The aim of this study was to monitor the development of 211 twin pregnancies in high producing dairy cows in order to determine the best time for an embryo reduction approach. Pregnancy was diagnosed by transrectal ultrasonography between 36 and 42 days after insemination. Animals were then subjected to weekly ultrasound examination until Day 90 of gestation or until pregnancy loss. Viability was determined by monitoring the embryonic/fetal heartbeat until Day 50 of pregnancy, and then by heartbeat or fetal movement detection. Eighty-six cows (40.8%) bore bilateral and 125 (59.2%) unilateral twin pregnancies. Embryo death was registered in one of the two embryos in 35 cows (16.6%), 33 of them at pregnancy diagnosis. Pregnancy loss occurred in 22 of these cows between 1 and 4 weeks later. Thus, 13 (6.2% of the total animals) cows, carrying one dead of the two embryos, maintained gestation. Total pregnancy loss before Day 90 of pregnancy (mean 69 +/- 14 days) was registered in 51 (24.2%) cows: 7 (8%) of bilateral pregnancies and 44 (35.2%) of unilateral pregnancies, and it was higher (P = 0.0001) for both right (32.4%, 24/74) and left (39.2%, 20/51) unilateral than for bilateral (8.1%, 7/86) twin pregnancies. The single embryo death rate was significantly (P = 0.02) lower for cows with bilateral twins (9.3%, 8/86) than for total cows with unilateral twins (21.6%, 27/125). By way of overall conclusion, embryo reduction can occur in dairy cattle, and the practical perspective remains that most embryonic mortality in twins (one of the two embryos) occurs around Days 35-40 of gestation, the period when pregnancy diagnosis is generally performed and when embryo reduction could be tried.

[Reverse flow in fetal vessels and perinatal events]

BACKGROUND/PATIENTS: A reverse flow in the umbilical artery and/or fetal aorta is associated with a higher perinatal and neonatal mortality. 30 fetuses showed a reverse flow using pulsed wave Doppler sonography (group I). A matched-pair control group including 30 fetuses with the same gestational age as well as a normal Doppler flow pattern in the umbilical artery and/or fetal aorta was taken for comparison (group II).

RESULTS

In the group with reverse flow the rates of pregnancies with pre-eclampsia (n = 19/30, p < 0.0001), intrauterine growth retardation (n = 25/30, p < 0.0001), oligohydramnios (n = 21/30, p < 0.0001) and nicotine abuse (n = 15/30, p < 0.01) were significantly higher compared to the control group. Postnatal data showed significantly lower pH values in group I (p < 0.01). 40 % of the fetuses with reverse flow died in utero whereas in 67 % the reverse flow was accompanied by an insufficiency of the placenta (IUGR, oligohydramnios, histopathological abnormalities of the placenta). None of the fetuses in the control group died in utero. The incidence of IUGR (< 5ht percentile) was 83 % in group I but only 3 % in group II. The perinatal and overall mortality (including neonatal mortality 7 - 28 days after birth) amounted to 27 % and 53 % in group I, respectively, compared to 3 % and 0 % in the control group (p < 0.001). In addition cerebral anomalies could be found by ultrasound in 50 % of the neonates who presented a reverse flow prenatally. In 28 % of the surviving newborns an intracerebral hemorrhage (ICH) could be detected. None of the newborns of group II developed an ICH.

CONCLUSIONS

Pregnancies with a reverse flow in the umbilical artery and/or fetal aorta have to be considered as a high risk group with a poor prognosis. The reverse flow is mainly caused by chronic placental insufficiency with IUGR. With respect to the further neuromotor development the incidence and severity of cerebral lesions in affected fetuses should be considered when discussing the perinatal situation with the parents.

Differential Transmission of Parvovirus B19 in a Twin Gestation: A Case Report

Maternal infection with parvovirus B19 during pregnancy can cause aplastic anemia in the fetus. Severe anemia may lead to nonimmune hydrops or fetal demise. In the case reported, the demise of one twin was diagnosed by ultrasonography in an asymptomatic 21-year-old para 1-0-2-1 African American at the gestational age of 25 weeks. The deceased twin (A) was grossly hydropic with anasarca, ascites, pleural and pericardial effusions, and a thickened placenta. Parvovirus B19 DNA was found in the amniotic fluid of Twin A using the polymerase chain-reaction technique. Serial scans of Twin B showed normal growth and no evidence of hydrops. The pregnancy was managed expectantly until 29 weeks when delivery was indicated by maternal disseminated intravascular coagulation. Maternal IgM antiparvovirus B19 antibodies were detected at the time of delivery. Antiparvovirus B19 IgM antibodies were not present in Twin B. These serologic studies suggest a recent acute maternal infection and refute such an infection in Twin B. We present a case of differential transmission of parvovirus B19 in a twin pregnancy with in utero death of the infected twin and subsequent maternal disseminated intravascular coagulation.