Incidence of congenital heart disease in fetuses diagnosed with single isolated umbilical artery. Systematic review and meta-analysis

OBJECTIVE

To estimate the proportion of heart disease in fetuses with a prenatal diagnosis of a single isolated umbilical artery.

METHODS

We performed a search strategy in MEDLINE (OVID), EMBASE, and the Cochrane Central Register of Controlled Trials (CENTRAL) from inception to the present. We assessed the risk of bias and performed a meta-analysis. We completed the subgroup analysis according to the region.

RESULTS

We found 1384 studies by the search strategy. After carefully reviewing the full-text, 15 studies were included. A total of 2008 fetuses with a single isolated umbilical artery were included, and 177 had cardiac malformations. There was an overall incidence of 9% 95%CI (0.05-0.14) I2 90%. The incidence by country of origin was between 5% and 19%. The most common heart disease reported was a ventricular septal defect. Seven studies were found describing 25 cases. We described other malformations, such as tetralogy of Fallot, coarctation of the aorta, and hypoplastic left ventricle, among others.

CONCLUSION

The incidence of congenital heart disease in fetuses with a single isolated umbilical artery was high. In addition, half of these correspond to significant heart disease. Based on the above, we suggest that fetuses with a single isolated umbilical artery should have a complete anatomic evaluation emphasizing cardiac evaluation.

Umbilical artery thrombosis: Two case reports

RATIONALE

The umbilical cord is the way to exchange gas, supply nutrients, excrete metabolized. Thrombosis of the umbilical cord leads to fetal hypoxia, which jeopardizes fetal health and can cause fetal death. Umbilical vessel thrombosis, which is rarely reported, is difficult to detect prenatally.

PATIENT CONCERNS

Both pregnant women had an unremarkable pregnancy course until a routine ultrasound scan in the third trimester showed a single umbilical artery. However, one umbilical vein and 2 umbilical arteries were seen during an ultrasound examination at 32 weeks. Case 2 had a better pregnancy outcome because of the timely discovery of this complication.

DIAGNOSIS

Both cases were diagnosed as umbilical artery thrombosis.

INTERVENTIONS

The first patient received no interventions until they reported decreased fetal movements and gradually disappear. The second patient underwent an emergency cesarean section.

OUTCOMES

In Case 1, an emergency ultrasound examination showed intrauterine fetal death, and the patient vaginally delivered a stillborn child weighing 3300 g in a day. In Case 2, a female neonate weighing 2860 g was delivered by cesarean section, and exhibited Apgar scores of 10 and 10 at 1 and 5 minutes.

CONCLUSION

In the late-term abortions, obstetricians should be vigilant if ultrasound imaging shows suspected umbilical vascular thrombosis or shows 1 umbilical artery when there had previously been 2. The fetus should be closely monitored and interventions implemented as early as possible to improve the prenatal detection rate of umbilical vessel thrombosis and avoid adverse pregnancy outcomes.

Antibody to Marinobufagenin Reverses Placenta-Induced Fibrosis of Umbilical Arteries in Preeclampsia

Background: Previous studies implicated cardiotonic steroids, including Na/K-ATPase inhibitor marinobufagenin (MBG), in the pathogenesis of preeclampsia (PE). Immunoneutralization of heightened MBG by Digibind, a digoxin antibody, reduces blood pressure (BP) in patients with PE, and anti-MBG monoclonal antibody lessens BP in a rat model of PE. Recently, we demonstrated that MBG induces fibrosis in cardiovascular tissues via a mechanism involving inhibition of Fli-1, a nuclear transcription factor and a negative regulator of collagen-1 synthesis. Objectives and Methods: We hypothesized that in PE, elevated placental MBG levels are associated with development of fibrosis in umbilical arteries. Eleven patients with PE (mean BP 124 ± 4 mmHg; age 29 ± 2 years; 39 weeks gest. age) and 10 gestational age-matched normal pregnant subjects (mean BP 92 ± 2 mmHg; controls) were enrolled in the clinical study. Results: PE was associated with a higher placental (0.04 ± 0.01 vs. 0.49 ± 0.11 pmol/g; p < 0.01) and plasma MBG (0.5 ± 0.1 vs. 1.6 ± 0.5 nmol/L; p < 0.01), lower Na/K-ATPase activity in erythrocytes (2.7 ± 0.2 vs. 1.5 ± 0.2 µmol Pi/mL/hr; p < 0.01), 9-fold decrease of Fli-1 level and 2.5-fold increase of collagen-1 in placentae (p < 0.01) vs. control. Incubation of umbilical arteries from control patients with 1 nmol/L MBG was associated with four-fold decrease in Fli-1 level and two-fold increase in collagen-1 level vs. those incubated with placebo (p < 0.01), i.e., physiological concentration of MBG mimicked effect of PE in vitro. Collagen-1 abundance in umbilical arteries from PE patients was 4-fold higher than in control arteries, and this PE-associated fibrosis was reversed by monoclonal anti-MBG antibody ex vivo. Conclusion: These results demonstrate that elevated placental MBG level is implicated in the development of fibrosis of the placenta and umbilical arteries in PE.

Short umbilical cord length: reflective of adverse pregnancy outcomes

A short umbilical cord is associated with adverse pregnancy outcomes. However, there is no universally accepted definition of a short cord.

OBJECTIVE

This study aimed to determine the umbilical cord length showing the highest correlation with adverse pregnancy outcomes.

MATERIALS AND METHODS

The authors retrospectively analyzed the clinical data of women who attempted vaginal birth in the present institution. Umbilical cord lengths were categorized into three groups: less than the first percentile, from the first percentile to less than the tenth percentile, and others. Maternal and neonatal characteristics previously suggested to affect cord length were evaluated. The main outcome was the rate of cesarean delivery. The authors also evaluated the frequency of operative vaginal delivery, small-for-gestational-age (SGA) births, neonatal intensive care unit (NICU) admission, umbilical artery pH < 7.1, and abnormal bleeding during delivery.

RESULTS

Cord lengths of 35 and 45 cm corresponded to the first and tenth percentiles, respectively. A short cord was an indi- cator of unplanned cesarean delivery and small-for-gestational-age births.

CONCLUSION

An umbilical cord length of ≤ 45 cm is a clinically useful indicator of adverse pregnancy outcomes.

The Effects of Low-Dose Endotoxin on the Umbilicoplacental Circulation in Preterm Sheep

OBJECTIVE

In the present study we examined the effects of low-dose endotoxin (lipopolysaccharides, LPS) on continuously recorded umbilical blood flow.

METHODS

Twenty fetal sheep were catheterized at a gestational age of 107 +/- 1 days. A flow probe was placed around either the common umbilical artery or one single umbilical artery. Three days later fetuses received either 100 or 500 nanograms of LPS (n = 14) or 2 mL saline (n = 6) intravenously. Six fetuses died within 12 hours after LPS. Fetal heart rate (FHR), mean arterial pressure (MAP), and umbilical blood flow (Q(umb)) were monitored for 3 days.

RESULTS

FHR increased by 25 +/- 4% at 4-5 hours after LPS (P <.01) and was elevated for 15 hours after LPS. MAP increased by 18 +/- 5% 1 hour after LPS (P <.01) and returned to control value 4-5 hours after LPS. Q(umb) began to decrease 1 hour after LPS and was minimal (-30 +/- 7%, P <.001) at 4-5 hours after LPS. Q(umb) slowly returned to the control value at 12 hours after LPS. Placental vascular resistance increased by 73 +/- 37% (P <.01), whereas pH did not appreciably change.

CONCLUSION

Intravenous application of endotoxin caused a substantial and long-lasting decrease in umbilical blood flow resulting in fetal hypoxemia without acidemia. These effects may be of significance in the development of fetal brain damage associated with intrauterine infection.

Intrauterine thrombosis of umbilical artery - case report

CONTEXT

Umbilical cord thrombosis is related to greater fetal and perinatal morbidity and mortality. It is usually associated with umbilical cord abnormalities that lead to mechanical compression with consequent vascular ectasia. Its correct diagnosis and clinical management remains a challenge that has not yet been resolved.

CASE REPORT

This study reports a case of umbilical artery thrombosis that occurred in the second half of a pregnancy. The umbilical cord was long, thin and overly twisted and the fetus presented severe intrauterine growth restriction. The clinical and histopathological findings from this case are described.

CONCLUSIONS

This case report emphasizes the difficulty in diagnosing and clinically managing abnormalities of intrauterine life with a high chance of perinatal complications.

Infection of Internal Umbilical Remnant in Foals by Clostridium sordellii

Omphalitis and the resulting septicemia contribute to perinatal mortality in several animal species. In foals, the most important causes of omphalitis are Escherichia coli and Streptococcus zooepidemicus. However to date, no information has been published about the role of Clostridium sordellii in these infections. In this paper, we describe 8 cases of perinatal mortality in foals associated with internal umbilical remnant infection by C. sordellii. The foals studied were between 12 and 21 days old at the time of death, and various breeds were represented in the group. Five of the foals were male and 3 were female. The diagnosis was established on the basis of the detection of C. sordellii by 3 methods (culture, fluorescent antibody test, and immunohistochemistry) and on gross and histopathologic findings. All foals had acute peritonitis, and the internal umbilical remnant was thickened by edema, hemorrhage, and fibrosis. A moderate amount of serosanguinous fluid with fibrin strands was present in the pericardial sac and pleural cavity. Histopathologically, the urachus and umbilical arterial walls were thickened by edema and exhibited hemorrhage, fibrin, and leukocytic infiltration. Gram-positive bacterial rods were observed in subepithelial areas of the urachus, the adventicia of umbilical arteries, and interstitium of the internal umbilical remnant. On the basis of these findings, we suggest that C. sordellii should be considered in the differential diagnosis for infections of the internal umbilical remnant in foals.

[ASPHYXIA IN INTRAUTERINE GROWTH RESTRICTION OF THE FETUS- CARDIOTOCOGRAPHY AND ULTRASOUND METHODS OF DIAGNOSIS.]

Fetal asphyxia remains an important cause of neonatal morbidity and mortality. The tests in themselves (cardiotocography (NST), sonography, Doppler studies) which are used for antenatal fetus surveillance are aimed at timely diagnosing the signs of the fetus asphyxia. The objective of the current research is to study which modifications in the cardiotocography (NST), arterial and venosus Doppler correlate most strongly with severe asphyxia pH< 7.10 and BE≥12 mmol/l regarding pregnancies which are complicated with intrauterine growth restriction of the fetus. The presence of spontaneous decelerations in the cardiotocography shows sensitivity 81.3%, specificity 97.1%, positive predictive value (PPV) 83.2, negative predictive value (NPV) 98.2%, odds ratio (OR) 260, p< 0.0001, the reversed blood velocity of artery umbilicalis shows sensitivity 58.3%, specificity 96.2%, PPV 63.6%, NPV 95. 3% OR 35.7 p< 0.001, reversed a-wave ductus venosus shows sensitivity 51%, specificity 94.3%, PPV 48% NPV 93.2% OR 16.7, p< 0.001. Concerning pregnant women with intrauterine growth restriction of the fetus the prognostication of severe fetus asphyxia at delivery - pH<7. 10 and BE -12 mmol/I with the highest specificity of antenatal testing is the occurrence of spontaneous decelerations in NST, the reversed blood velocity of umbilical artery and the reversed a-wave ductus venosus in Doppler studies.

Prognostic value of umbilical and cerebral Doppler in fetal growth restriction: comparison of dichorionic twins and singletons

Objective

To compare the prognostic value of fetal Doppler in dichorionic twins and singletons by measuring the interval between diagnosis of an abnormal Doppler flow and birth in fetuses who are small for gestational age (SGA).

Design

Comparative retrospective study using a prospectively collected database.

Setting

A level 3 maternity unit in France.

Population

Fetuses from singleton and dichorionic pregnancies who are SGA (vascular or unexplained), defined by an abdominal circumference (AC) measurement below the 10^th percentile and confirmed by a birth weight below the 10^th percentile.

Methods

Fisher's exact and Chi-2 tests were used to compare frequencies, and the Mann-Whitney-Wilcoxon test was used to compare medians in non-Gaussian distributions.

Main outcome measures

Both neonatal outcomes and intervals between the first Doppler abnormality and birth were compared in the groups of dichorionic twins and singletons.

Results

Obstetric and neonatal outcome were similar in the 104 SGA dichorionic twins and 170 SGA singletons. Abnormalities of umbilical artery Doppler, regardless of type, appeared at the same frequency in both groups (52.9%) but were identified earlier in twins (25 versus 28 weeks, p = 0.02). Among fetuses with abnormal Doppler flow, the interval between the finding and birth was significantly longer in the twins than the singletons (44 vs 15 days, p<0.01).

Conclusions

The prognostic value of an abnormal Doppler finding for the course of a pregnancy may be different in dichorionic twins and singletons. The management of women carrying SGA twins and the information provided to them should take these results into account.

[Spontaneous intrauterine rupture of the umbilical cord is very uncommon but a serious condition]

Spontaneous intrauterine rupture of the umbilical cord is an uncommon and dangerous complication during delivery. We describe a case of a 27-year-old woman with a normal pregnancy. When the membranes broke, the fetal heart sounds suddenly disappeared, and the vaginal bleeding was heavier than normal. An emergency caesarean section was executed and the examination of the placenta revealed a broken umbilical artery. The child was born with an Apgar score of 0,1,1 and a blood gas analysis from the umbilical vein showed pH 6.68 and Base Excess -24.3. Urgent treatment with heart massage, adrenaline, blood transfusion and tribonate was initiated and followed by therapeutic hypothermia. The child was discharged after 10 days with no pathological findings on a MRI examination of the brain. The 6 month follow-up showed a normal development. When a fetal bleeding is suspected, it is important to inform a neonatologist so that correct treatment can be started as early as possible.

The site of attachment of umbilical cord and branching pattern of umbilical arteries within the placenta

Placenta is the mirror of maternal and fetal status; it reflects the changes due to complication in pregnancy of mother. Numerous common and uncommon findings of the placenta, umbilical cord and membranes are associated with abnormal fetal development and perinatal morbidity. So, the examination of the placenta can yield information that may be important in the immediate and later management of mother and newborn. This information may also be essential for protecting the attending physician in the event of an adverse maternal or fetal outcome. This cross sectional descriptive study was carried out to determine the incidence of different types of placenta depending on attachment site and branching pattern of arteries of umbilical cord in Bangladeshi Women. To achieve this aim sixty placenta with umbilical cord were collected. Placenta was from 28 weeks to 42 weeks gestational age of normal pregnancy during normal labour at gynaecology and obstetric department of Mymensingh Medical College Hospital. After preservation in 10% formol saline, study was done in the Department of Anatomy of Mymensingh Medical College. In the present study, incidence of different types of placenta depending on attachment site of umbilical cord was 50% Central, 46% Paracentral and 18% Marginal in type. In this study it was also observed that 58% placenta were Disperse in type and 42% were Magistral in type depending on the distribution of umbilical arteries. Observed findings of this study were compared with those of Western and Bangladeshi researchers.

Directing vascular cell selectivity and hemocompatibility on patterned platforms featuring variable topographic geometry and size

It is great challenge to generate multifunctionality of vascular grafts and stents to enable vascular cell selectivity and improve hemocompatibility. Micro/nanopatterning of vascular implant surfaces for such multifunctionality is a direction to be explored. We developed a novel patterned platform featuring two typical geometries (groove and pillar) and six pattern sizes (0.5-50 μm) in a single substrate to evaluate the response of vascular cells and platelets. Our results indicate that targeted multifunctionality can be indeed instructed by rationally designed surface topography. The pillars nonselectively inhibited the growth of endothelial and smooth muscle cells. By contrast, the grooves displayed selective effects: in a size-dependent manner, the grooves enhanced endothelialization but inhibited the growth of smooth muscle cells. Moreover, our studies suggest that topographic cues can affect response of vascular cells by regulating focal adhesion and stress fiber development, which define cytoskeleton organization and cell shape. Notably, both the grooves and the pillars at 1 μm size drastically reduced platelet adhesion and activation. Taken together, these findings suggest that the topographic pattern featuring 1 μm grooves may be the optimal design of surface multifunctionality that favors vascular cell selectivity and improves hemocompatibility.

Changes in fetal Doppler indices as a marker of failure to reach growth potential at term

OBJECTIVE

To evaluate whether changes in the middle cerebral artery (MCA), umbilical artery (UA) and cerebroplacental ratio (CPR) Doppler indices at term might be used to identify those appropriate-for-gestational-age (AGA) fetuses that are failing to reach their growth potential (FRGP).

METHODS

This was a retrospective cohort study of data obtained in a single tertiary referral center over a 10-year period from 2002 to 2012. The UA pulsatility index (PI), MCA-PI and CPR were recorded between 37+0 and 41+6 weeks within 14 days before delivery. The Doppler parameters were converted into multiples of the median (MoM), adjusting for gestational age, and their correlation with birth-weight (BW) centiles was evaluated by means of regression analysis. Doppler indices were also grouped according to BW quartiles and compared using Kruskal-Wallis and Dunn's post-hoc tests.

RESULTS

The study included 11576 term fetuses, with 8645 (74.7%) classified as AGA. Within the AGA group, fetuses with lower BW had significantly higher UA-PI, lower MCA-PI and lower CPR MoM values. Large-for-gestational-age (LGA) fetuses were considered as the group least likely to be growth-restricted. The CPR MoM < 5(th) centile (0.6765 MoM) in these fetuses was used as a threshold for diagnosing FRGP. Using this definition, in the AGA pregnancies the percentage of fetuses with FRGP was 1% in the 75-90(th) BW centile group, 1.7% in the 50-75(th) centile group, 2.9% in the 25-50(th) centile group and 6.7% in the 10-25(th) centile group.

CONCLUSION

AGA pregnancies may present with fetal cerebral and placental blood flow redistribution indicative of fetal hypoxemia. Fetal Doppler assessment may be of value in detecting AGA pregnancies that are subject to placental insufficiency, fetal hypoxemia and FRGP. Future studies are needed to evaluate the appropriate threshold for the diagnosis of FRGP and the diagnostic performance of this new approach for the management of growth disorders.

Obstetric and perinatal outcomes in IVF versus ICSI-conceived pregnancies at a tertiary care center--a pilot study

BACKGROUND

Although most pregnancies after IVF result in normal healthy outcomes, an increased risk for a number of obstetric and neonatal complications, compared to naturally conceived pregnancies, has been reported. While there are many studies that compare pregnancies after assisted reproductive techniques with spontaneously conceived pregnancies, fewer data are available that evaluate the differences between IVF and ICSI-conceived pregnancies. The aim of our present study was, therefore, to compare obstetric and perinatal outcomes in pregnancies conceived after in vitro fertilization (IVF) versus intracytoplasmatic sperm injection (ICSI).

METHODS

Three-hundred thirty four women who had become pregnant after an IVF or ICSI procedure resulted in a total of 530 children referred between 2003 und 2009 to the Department of Obstetrics and Gynecology of the Medical University of Vienna, a tertiary care center, and were included in this retrospective cohort study. We assessed maternal and fetal parameters in both groups (IVF and ICSI). The main study outcomes were preterm delivery, the need for neonatal intensive care, and congenital malformations. Moreover, we compared the course of pregnancy between both groups and the occurrence of complications that led to maternal hospitalization during pregnancy.

RESULTS

There were 80 children conceived via ICSI and 450 children conceived via IVF.Mean gestational age was significantly lower in the ICSI group (p = 0.001). After ICSI, the birth weight (p = 0.008) and the mean APGAR values after 1 minute and after 10 minutes were lower compared to that of the IVF group (p = 0.016 and p = 0.047, respectively). Moreover, ICSI-conceived children had to be hospitalized more often at a neonatal intensive care unit (p = 0.004). There was no difference in pH of the umbilical artery or in major congenital malformations between the two groups. Pregnancy complications (i.e., premature rupture of membranes, cervical insufficiency, and premature uterine contractions) and the need for maternal hospitalization during pregnancy were found significantly more often after IVF (p = 0.0016 and p = 0.0095, respectively), compared to the ICSI group.

CONCLUSIONS

When comparing IVF versus ICSI-conceived pregnancies at a tertiary care center, we found the course of pregnancy to be more complicated after IVF, whereas the primary fetal outcome seemed to be better in this group than after ICSI treatment.

High-intensity focused ultrasound treatment for twin reversed arterial perfusion sequence

Twin reversed arterial perfusion (TRAP) sequence is a serious complication of monochorionic twin pregnancies, in which arterioarterial anastomoses allow blood flow from a 'pump' fetus to an acardiac fetus via reversed flow in the latter's umbilical artery. Several trial treatments for TRAP sequence have been reported, but all of these have been invasive. We present a case of TRAP sequence in which high-intensity focused ultrasound (HIFU) was applied to the umbilical artery of the anomalous twin at 26 weeks as a non-invasive fetal therapy. The HIFU intensity was set at approximately 2300 W/cm(2) with exposure periods of 10 s. Color Doppler ultrasound showed a decrease in blood supply to the anomalous twin, although complete occlusion of the targeted vessel was not achieved. Delivery was by Cesarean section at 29 weeks' gestation and the pump twin survived, without severe clinical complications at 6 months.

Deformation of the left and right ventricular longitudinal myocardium in fetuses with umbilical cord around neck

BACKGROUND

Umbilical cord around neck, a common obstetric complication, affects fetal hemodynamics. Does it influence fetal cardiac functions? The purpose of this study was to investigate the left and right ventricular systolic and diastolic functions of fetuses with umbilical cord around neck in the third trimester by applying velocity vector imaging (VVI).

METHODS

Thirty-five cases of fetuses with umbilical cord around neck whose gestational ages from 35 to 40 weeks were selected, including 20 cases of umbilical artery ratio of the highest systolic velocity (S) to the lowest diastolic velocity (D) (S/D) < 3.0 and 15 cases of umbilical artery S/D ≥ 3.0, while 20 cases of normal fetuses of 35 - 40 gestational weeks were selected as the control group. The changes in longitudinal velocity, strain, and strain rate of fetal left and right ventricle in systole and diastole in two groups, and the changes in fetal cardiac function under the situation of umbilical cord around neck were analyzed.

RESULTS

Longitudinal strain and strain rate overall of fetal left and right ventricle in systole and diastole were less in fetuses with umbilical artery S/D (3)3.0 and umbilical cord around neck than those in fetuses with umbilical artery S/D < 3.0 and those in control group (P < 0.05); there was no significant difference (P > 0.05) in longitudinal strain and strain rate overall of fetal left and right ventricle in systole and diastole between fetuses with umbilical artery S/D < 3.0 and those in control group.

CONCLUSIONS

Left and right ventricular systolic and diastolic dysfunction was detected in fetuses with umbilical cord around neck and umbilical artery S/D (3)3.0. VVI could sensitively respond to cardiac function changes in fetuses with umbilical cord around neck, which provides another valuable method in the evaluation of fetal cardiac function.

Diagnosis and management of central-line-associated thrombosis in newborns and infants

Although the use of central lines has many valuable applications in neonates and infants, they may cause serious mechanical, infectious and thrombotic complications. In fact, the use of central lines is the main cause for thrombosis in this age group. The frequency of central-line-related thrombosis in neonates and infants is reported to be as low as 1% when including only symptomatic cases, around 44% when systematically screened for thrombosis, and as high as 65% in autopsy studies. The risk factors for line-related thrombosis in neonates and infants include those associated with the underlying medical conditions, the duration of the line in situ, the placement of the umbilical artery catheter and the therapy used through the line. The contribution of inherited and acquired thrombophilia to central-line-related thrombosis is controversial, and the data are not sufficiently consistent to make a firm recommendation for thrombophilia screening for neonates and infants with central-line-related thrombosis. Most experts will recommend pursuing a thrombophilia work-up in the setting of a significant thrombosis event and will recommend avoiding thrombophilia work-up in subclinical and asymptomatic central-line-related thrombosis. The management of line-related thrombosis is based on expert opinion guidelines and is largely dependent on the type of the catheter and the further requirement of the catheter. Continuous heparin infusion through the central lines prevents catheter occlusion, but has no effect on occurrence of thrombosis. Currently no definitive recommendations exist for thromboprophylaxis in children, infants and neonates with central lines.

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.

MicroRNAs are necessary for vascular smooth muscle growth, differentiation, and function

OBJECTIVE

Regulation of vascular smooth muscle (VSM) proliferation and contractile differentiation is an important factor in vascular development and subsequent cardiovascular diseases. Recently, microRNAs (miRNAs) have been shown to regulate fundamental cellular processes in a number of cell types, but the integrated role of miRNAs in VSM in blood vessels is unknown. Here, we investigated the role of miRNAs in VSM by deleting the rate-limiting enzyme in miRNA synthesis, Dicer.

METHODS AND RESULTS

Deletion of Dicer in VSM results in late embryonic lethality at embryonic day 16 to 17, associated with extensive internal hemorrhage. The loss of VSM Dicer results in dilated, thin-walled blood vessels caused by a reduction in cellular proliferation. In addition, blood vessels from VSM-deleted Dicer mice exhibited impaired contractility because of a loss of contractile protein markers. We found this effect to be associated with a loss of actin stress fibers and partly rescued by overexpression of microRNA (miR)-145 or myocardin.

CONCLUSIONS

Dicer-dependent miRNAs are important for VSM development and function by regulating proliferation and contractile differentiation.

Uterine venous blood flow in normal and complicated pregnancies: a methodological study

OBJECTIVE

To investigate the possibility of recording Doppler flow signals from the maternal uterine veins (UtVs) during pregnancy and to assess the relationship between UtV signals and other Doppler parameters as well as pregnancy outcomes.

METHODS

Transabdominal Doppler ultrasound examination of the UtVs on both sides of the uterus was performed in 40 normal and 44 high-risk singleton pregnancies at 23-39 weeks' gestation. The UtV was identified using color Doppler imaging and the flow velocity signals of the UtV and uterine artery (UtA) were recorded. Morphological examination of the placenta was carried out in 45 of the pregnancies (14 uncomplicated and 31 high-risk pregnancies).

RESULTS

Flow-velocity signals of the UtVs were recorded from at least one side of the uterus in all patients (success rate of 81 and 89% for the right and left UtV, respectively). Three types of flow-velocity pattern were identified: continuous non-pulsatile flow (Type I, n = 70), pulsatile flow with a notch touching the zero line (Type II, n = 6) and pulsatile flow with absent flow signals for part of the heart cycle (Type III, n = 8). The UtA pulsatility index was significantly higher in women with UtV Types II and III than in those with UtV Type I (P = 0.039). Similarly, UtV Types II and III were more often found in pregnancies with bilateral UtA notching (P = 0.013) and with UtA score 3-4 (P = 0.024) than in those with normal UtA. No statistically significant association was found between the UtV flow pattern and abnormal histopathological findings in the placenta, or between the UtV and umbilical artery findings.

CONCLUSION

It is possible to record Doppler signals from the UtVs in the late second and third trimesters of pregnancy. Pulsatile flow-velocity patterns of the UtVs are associated with abnormal UtA Doppler findings.

Umbilical cord morphology in pregnancies complicated by IUGR in cases of tobacco smoking and pregnancy-induced hypertension

OBJECTIVE

The aim of this study was to determine the characteristic features of the umbilical cord morphology in selected cases of intrauterine growth restriction (IUGR): tobacco smoking, pregnancy-induced hypertension and idiopathic IUGR.

MATERIALS AND METHODS

136 pregnant women were included in the study - 86 patients with IUGR (IUGR group) and 50 women with uncomplicated course of pregnancy (control group). In the IUGR group 31 women were smokers, 27 suffered from pregnancy-induced hypertension, and 28 had an unknown reason for IUGR. Each of them underwent ultrasound examination to measure fetal growth and to assess morphological parameters of the umbilical cord.

RESULTS

Significant differences between the control group and the whole IUGR group in terms of the diameter of the umbilical cord and diameter of the umbilical vein - smaller diameters in the IUGR group than in the control group. Significant differences among IUGR subgroups in terms of area of Wharton's jelly and diameters of the umbilical cord, vein and artery. Significant difference in the length of the uncoiled section among the IUGR subgroups.

CONCLUSIONS

1. The umbilical cord in IUGR and concomitant tobacco smoking is hyper-coiled with coiling index independent of fetal weight and high content of Wharton's jelly. 2. The umbilical cord in IUGR and concomitant pregnancy-induced hypertension is thinnest with thinnest vessels and the smallest content of Wharton's jelly. 3. The assessment of umbilical cord morphology should become an integral part of ultrasound exam in pregnancies complicated by IUGR.

Mean platelet volume: Association with adverse neonatal outcome

The aim of the study was to investigate on a possible association between maternal mean platelet volume (MPV) and oxygen-metabolic changes in pregnancies affected by altered maternal-fetal Doppler velocimetry. We considered the altered maternal-fetal Doppler velocimetry group (n = 57) pregnant women admitted to our Institution for a pregnancy complication associated to the event Pre-eclampsia (PE) and intrauterine growth retardation (IUGR), with altered Doppler velocimetry in the umbilical artery ( UA) (high pulsatility index, absence or reverse end diastolic flow (ARED), blood flow cephalisation) and/or bilateral increased resistance in uterine arteries. Out of these cases, 25 pregnancies were complicated by PE and 32 pregnancies were complicated by IUGR. We included 145 normotensive third trimester pregnant women as a normal maternal-fetal Doppler velocimetry control group. From all women, 20 ml of whole venous blood was obtained from the antecubital vein soon after Doppler velocimetry evaluation. MPV was significantly higher in women with abnormal Doppler velocimetry compared to those with normal Doppler velocimetry (8.0 fl [7.0-8.7] vs. 9.1 fl [8.0-10.6], <0.001. Values are median [interquartiles]). We performed a ROC curve in order to find an MPV cut-off able to predict an uneventful event in Doppler velocimetry compromised fetuses (neonatal O(2) support > 48 hrs or intubation and/or pH < 7.2 at umbilical blood gas analysis (UBGA)). An MPV > or = 10 fl was significantly related to the former diagnostic endpoints compared to that of non-compromised fetuses (sensitivity: 45%, specificity: 89.7%, 95 CI: 18.8-66, p < 0.01). Our study suggests that pregnancies affected by Doppler velocimetry alterations, an MPV value > or = 10 fl may be associated with severe oxygen support and/or low UA ph at birth.

Umbilical cord ulceration causing foetal haemorrhage and stillbirth

We report a case of umbilical cord ulceration associated with obstruction of the duodeno-jejunal junction by a peritoneal band. Umbilical cord ulceration is a rare condition; a literature review identified a total of 17 cases only. In all cases, the ulceration was associated with congenital intestinal obstruction. Cord ulceration usually presents as sudden foetal deterioration due to foetal haemorrhage. This condition is associated with high perinatal mortality and morbidity. The causes of this condition are still unknown, and prenatal diagnosis is difficult. Awareness of the possible association between umbilical cord ulceration and intestinal obstruction, and of the need to deliver such pregnancies immediately when an abnormal foetal heart rate pattern develops might be the only means of preventing intrauterine death and improving neonatal outcomes.

Absence of Wharton's jelly around the umbilical arteries

Wharton's jelly is a specialized tissue which acts as supportive and protective structure substituting for the adventitia of the umbilical vessels. Absence of Wharton's jelly around the umbilical arteries is very rare and an unusual cause of perinatal mortality. We report a case of absent Wharton's jelly around the umbilical arteries with patent vitellointestinal duct--a rare association.

Third trimester intrauterine fetal death caused by arterial aneurysm of the umbilical cord

Umbilical artery aneurysm (UAA) of the umbilical cord is an extremely rare lesion, with only 8 reported cases in the English-language literature; 7 of these were associated with significant fetal morbidity or mortality and 4 were associated with fetal trisomy 18. We report an additional case of UAA with normal karyotype that resulted in intrauterine growth restriction and fetal demise. It has been suggested that these aneurysms cause fetal hypoxia and intrauterine fetal death, either by compression of the umbilical vein or by acute kinking of the umbilical cord. Cytogenetic analysis should be performed in all cases diagnosed with this unusual lesion, and placental mosaicism for trisomy 18 should be excluded.

Angiolipoma located inside the obturator canal and supplied by the umbilical artery

During dissection of the retropubic region of a 55-year-old female cadaver, we encountered an angiolipoma located inside the obturator canal which was connected to the wall of the urinary bladder by a fibrous cord. The angiolipoma was supplied by a branch originating from the umbilical artery. Microscopically the benign soft tissue tumor was characterized by lobules of mature adipocytes and densely distributed networks of small and larger blood vessels, thus resembling typical histological features of an angiolipoma. Both the uncommon location of the angiolipoma and the abnormal branch of the umbilical artery entering the obturator canal should be taken into account during surgical procedures in this region, such as for orthopedic pelvic procedures, hernia repair or bladder/urethra-related interventions (e.g. transobturator tape, tension-free vaginal tape, colposuspension).

Vasa praevia after IVF: should there be guidelines? Report of two cases and literature review

The paper gives an illustration and reminder of the risk of problems with placentation resulting from IVF and embryo transfer. Reported here is one neonatal death related to vasa praevia when the condition was not diagnosed antenatally and a neonatal survival when vasa praevia was detected antenatally. A search of the English literature was performed using PubMed for 'vasa praevia and in vitro fertilization'. There were four articles that directly addressed this relationship. Case reports of IVF-embryo transfer pregnancies with vasa praevia and also studies that look at the incidence of vasa praevia in such pregnancies are included in this report. Hence, since vasa praevia is thought to be caused by a disturbed orientation of the blastocyst at implantation, it is probably related to the IVF-embryo transfer procedure. Screening of all IVF-embryo transfer pregnancies with transvaginal sonography and colour Doppler to rule out vasa praevia is recommended in the second trimester.

Three-dimensional assessment of the morphology of the umbilical artery in normal and pre-eclamptic placentas

AIM

Pre-eclampsia is one of the main causes of intrauterine growth retardation. Although there are many studies performed in this setting showing the course of the umbilical vessels within the umbilical cord along with its structural changes, studies are lacking with regard to intraplacental vasculature and its structural changes.

METHODS

We investigated whether the vascular pattern differed in preeclamptic placentas in terms of intraplacental course and morphometry of the umbilical artery by using vascular corrosion cast technique. Furthermore, cross-sections taken from umbilical artery branches at different levels within the placenta, were examined with both light and scanning electron microscopy (SEM).

RESULTS

Vascular corrosion casts generated in both pregnancy groups should be defined with the main umbilical artery divided into 2-4 primary branches. No significant difference was seen between normal and pre-eclamptic groups regarding the diameters of primary and secondary branches and the number of cotyledons contained (P > 0.05). However, microscopic studies demonstrated expanded intervillous spaces in the placentas of pre-eclamptic pregnancies. Under SEM, distortion on the endothelial surface of the umbilical artery and an increase in vessel diameter and wall thickness have been determined in pre-eclamptic placentas. Furthermore, the branching pattern and changes affecting the endothelial surface of the umbilical artery have been shown three-dimensionally in pre-eclamptic placentas, using corrosion cast technique and SEM, respectively.

CONCLUSION

While microscopic findings were consistent with the Doppler ultrasonography findings, namely higher systole/diastole ratio and increased resistance (RI) and pulsatile (PI) index in the umbilical artery, no clear morphometric change has been observed.

Effect of umbilical ring constriction on Wharton's jelly

OBJECTIVE

The turgor of Wharton's jelly depends on osmotic and hydrostatic pressures. We tested the hypothesis that umbilical ring constriction has an impact on umbilical venous hemodynamics and thus on the volume of Wharton's jelly.

METHODS

In a cross-sectional study of 237 low-risk singleton pregnancies, the cross-sectional area of the fetal end of the umbilical cord was determined using sonography at 20-41 weeks of gestation. The inner area of the two arteries and the vein was also measured and subtracted from the cord area to calculate the area of Wharton's jelly. Based on the Bernoulli equation, the degree of vein constriction at the umbilical ring was assessed using the blood velocity increment at the abdominal inlet. Regression analysis and SD-score statistics were used to construct mean values and to assess the effects. The dataset was also analyzed for gender-specific effects.

RESULTS

The umbilical cord cross-sectional area increased with gestational age during the period 20-31 weeks, remaining essentially stable thereafter. The Wharton's jelly increased with gestational age from 20 until 31-32 weeks of gestation and remained at the same level for the rest of the pregnancy. At mid-gestation, on average 70% of the cord cross-sectional area was occupied by Wharton's jelly; at 31 weeks and later this value was 60%. Umbilical vein constriction was associated with reduced umbilical cord cross-sectional area and Wharton's jelly in female fetuses (P = 0.0007 and P = 0.003, respectively), but not in male fetuses.

CONCLUSIONS

Under physiological conditions, umbilical ring constriction affects umbilical vein hemodynamics, with corresponding effects on the umbilical cord cross-sectional area and the amount of Wharton's jelly. Interestingly, the effects are gender-specific.

Umbilical Arterial Thrombosis with Vascular Wall Necrosis: Clinicopathologic Findings of 11 Cases

Thrombosis of umbilical cord vessels is associated with a high perinatal mortality. Most cases are venous thrombi, arterial thrombi are uncommon. To clarify clinical and pathological features of this entity, we reviewed 11 cases with umbilical artery thrombosis. The gestational ages were 33-40 (mean 36.8) weeks. Three cases (38%) were associated with severe intrauterine growth retardation and two cases (25%) led to intrauterine fetal deaths. All cases had completely occlusive thrombi of one umbilical artery. The arteries with thrombosis demonstrated partial necrosis of vascular wall. The pathogenesis is unclear, but nine cases (82%) had cord abnormalities (long cord, peripheral cord insertion, short cord with twist, funisitis). This paper is the first report of clinical and pathological features of umbilical artery thrombosis. The results of this study confirm the clinical importance and unique histological findings of umbilical artery thrombosis. The recognition of umbilical artery thrombosis is necessary to establish the diagnosis and treatment of this condition.

Sirenomelia of an intracytoplasmic sperm injection conceptus: a case report and review of mechanism

Postmortem dissection of the 18-week male conceptus, product of intracytoplasmic sperm injection (ICSI), demonstrated the hallmark findings of sirenomelia. The lower legs were fused and the left knee was rotated medially. Internal organs showed hypoplastic lungs, a multicystic kidney, and unilateral ureteral hypoplasia. The vitelline artery was absorbed, in a classic fashion, into the umbilical artery and communicated with the aorta at a point proximal to the iliac arteries. The tributaries distal to this point were hypoplastic. This finding is consistent with previously documented cases of sirenomelia and is thought to be the pathogenetic mechanism resulting in a vascular steal from the lower extremities. A rare finding was the presence of a penis on the dorsal side just below a perforate anus. In this case report, we discuss the pertinent clinical history and autopsy findings. A brief review of the mechanism thought to give rise to sirenomelia is provided. To our knowledge, this is the first reported case of sirenomelia in an ICSI conceptus.

Decellularized umbilical artery treated with thin polyelectrolyte multilayer films: potential use in vascular engineering

Decellularized allograft tissues have been identified as a potential extracellular matrix scaffold for tissue-engineered vascular substitutes. In order to improve the thromboresistance, it is necessary to pre-coat the intra-luminal vessel surface. Recently a new surface modification technique appeared, based on the alternate adsorption of positive and negative charged polyelectrolytes. Our objective was to develop an alternative vascular scaffold made of decellularized human umbilical arteries treated with a PAH/PSS polyelectrolyte multilayered film. The vessels luminal surfaces covered with the multilayer film were observed by electronic scanning microscopy. Our observations showed that the luminal surface is completely devoid of ECs following treatment with trypsin. A top view of the coated artery indicated that the multilayer uniformly covered internal surface of the vessels. The successful of the multilayer correct deposition and retention on the arterial wall were controlled by confocal microscopy using a fluorescent polyelectrolyte (rhodamine-PAH). The data suggest that decellularized cryopreserved arteries represent a potential scaffold for further vascular tissue engineering efforts. Moreover, the multilayer films can be used to coat biological surfaces and following the terminated layer (PAH or PSS), favour the cell adhesion or cell resistance.

Umbilical cord stricture and overcoiling are common causes of fetal demise

Although umbilical cord stricture and umbilical cord overcoiling have been established as causes of intrauterine fetal demise, relatively few studies addressed this issue, most of them being case reports. We reviewed a total of 268 fetal autopsies during a 3-year period from 1998 to 2001. One hundred thirty nine cases of fetal demise including spontaneous abortion were identified. Nineteen percent (26 of 139) were associated with umbilical cord stricture, overcoiling, or a combination of both. Stricture of the umbilical cord was defined as a decrease in diameter in relation of the remaining umbilical cord; overcoiling as 0.3 coil/cm or greater. Fetal demise most commonly occurred in the second trimester, with a mean gestation age of 21 weeks. The average maternal age was 33 years; 15% had a prior fetal demise. We found that 77% (20 of 26) of these cases had umbilical cord stricture only or with overcoiling, 23% (6 of 26) had umbilical cord overcoiling alone. Localized deficiency of Wharton's jelly and increased collagen were found in all cases with umbilical cord stricture with or without overcoiling. In patients with umbilical cord overcoiling alone, 25% had Wharton's jelly deficiency; half of them had increased collagen deposition in the umbilical cords. The placenta was reviewed for secondary thrombosis of the vessels of the chorionic plate. Thrombosis of the vessels of the chorionic plate was noted in 54% of the patients. Our study suggests that umbilical cord stricture and cord overcoiling may represent two distinct pathological entities commonly causing fetal demise. This observation reinforces the importance of a fetal autopsy with careful examination of the placenta and umbilical cord with documentation of the cord coil index.

Apoptotic and morphological features of the umbilical artery endothelium in mild and severe pre-eclampsia

BACKGROUND

The pathology of the umbilical arterial endothelium in normal pregnancy and in pregnancy complicated with pre-eclampsia remains unclear. In this study the changes that occur in the umbilical artery endothelial cells were examined and endothelial cell morphology and apoptosis were compared among control, mild, and severe pre-eclamptic subjects.

METHODS

Umbilical cords with a gestational age of between 35 and 40 weeks were collected from women with normal pregnancies (n=17), mild pre-eclampsia (n=10), and severe pre-eclampsia (n=12). We studied the umbilical artery endothelial cells using flow cytometry, and light and electron microscopy. Apoptosis was measured using flow cytometry and the terminal deoxynucleotidyl transferase deoxyuridine triphosphate nick end labeling technique. The Kruskall-Wallis variance analysis and Mann-Whitney U-tests as post hoc were applied.

RESULTS

In mild pre-eclamptics, the endothelial cells appeared ultrastructurally separated. A dilated endoplasmic reticulum, swollen mitochondria, and vanished mitochondrial cristae were observed. In severe pre-eclamptics, the cells were disorganized, highly contracted and vacuolated, separated from each other, and protruding prominently into the lumen. The percentages of endothelial cells that underwent apoptosis in mild (p<0.017) and severe pre-eclamptics (p<0.017) were higher than those in the controls. These apoptosis values were highest in severe pre-eclamptics (p<0.0001).

CONCLUSION

Apoptosis and structural disruptions in the arterial endothelium of severe pre-eclamptics were prominent in all subjects. Increased endothelial apoptosis and structural disruptions are clinically related to intensity of pre-eclampsia, and may be associated with adaptation of the endothelial cells to pre-eclampsia.

Placental lesions in a case of DiGeorge sequence

This work describes some placental alterations found in a partial form of DiGeorge sequence, namely, hypoplasia of a cord artery with internal calcification of an extensive endoluminal thrombosis, and widespread calcification of microthrombi in the arteries of the second and third order villous branches. Hypoplasia of a cord artery is a relatively rare event, and is also associated with malformations of the gastroenteric and cardiovascular system, as sometimes described in the DiGeorge sequence. Interesting placental alterations are reported and their likely physiopathologic basis and pathogenic correlation discussed in order to give a better and more comprehensive picture of the DiGeorge sequence in which the correlated placental alterations are not sufficiently known.

Usefulness of aspirin therapy in high-risk pregnant women with abnormal uterine artery Doppler ultrasound at 14-16 weeks pregnancy: randomized controlled clinical trial

AIM

To assess the effectiveness of low-dose aspirin in the prevention of preeclampsia and intrauterine growth restriction (IUGR) in high-risk pregnant women with abnormal findings at uterine artery Doppler velocimetry performed at 14-16 weeks.

DESIGN

Randomized controlled clinical trial.

SETTING

Department of Obstetrics and Gynecology, Faculty of Medicine, Cairo University, Egypt.

METHODS

The trial enrolled 139 women at risk of preeclampsia or IUGR, with abnormal uterine artery Doppler findings that included the presence of unilateral or bilateral diastolic notch, high resistance index (RI), or high pulsatility index (PI) at 14-16 weeks of gestation. The women were randomly allocated into two groups, one receiving aspirin since admission to hospital (n=74) and the other serving as control (n=65). All women were followed up until delivery to assess maternal and perinatal outcomes. T-test was used for comparison of quantitative variables, and categorical variables were compared by chi2 test. OUTCOME CRITERIA: Development of mild or severe preeclampsia, time of onset of preeclampsia, preterm delivery, and the development of IUGR.

RESULTS

Preeclampsia developed in 35% of women receiving aspirin and 62% of women in the control group (P=0.003), with severe preeclampsia developing in 8% and 23% of women (P=0.215), respectively. Preeclampsia before 37 weeks of gestation was recorded in only 4% of women receiving aspirin as opposed to 83% of controls (P<0.001). In the group of women receiving aspirin, 19% of newborns suffered from IUGR as opposed to 32%of newborns in the control group (P=0.106). There was no significant difference between the two groups in the rate of preterm delivery (P=0.080), mode of delivery (P=0.971), Apgar score <5 after one minute (P=0.273) and after 5 minutes (P=0.941), maternal or neonatal bleeding (P=0.948), and neonatal birth weight (P=0.399).

CONCLUSION

Low-dose aspirin administered as early as 14-16 weeks of gestation to pregnant women at high risk of preeclampsia with abnormal uterine Doppler findings may reduce or modify the course of severe preeclampsia. Its effects on the prevention of IUGR need further evaluation.

Extracellular matrix changes in the umbilical arteries of growth-restricted fetuses

OBJECTIVE

This study was undertaken to determine whether the expression of extracellular matrix components (ECM) is altered in the umbilical arteries from preterm fetal growth-restricted (FGR) pregnancies.

STUDY DESIGN

Preterm pregnancies with FGR were compared with appropriately grown preterm pregnancies. Umbilical artery messenger RNA (mRNA) levels for fibrillar collagens I and III, nonfibrillar collagen XIV, and decorin were determined by using relative reverse transcriptase polymerase chain reaction (RT-PCR). The mRNA expression was compared between cases and controls by using the Student t test. P < or = .05 was considered significant.

RESULTS

Eight FGR cases and 5 control pregnancies were analyzed. Mean counts per minute (cpm) +/- SEM for collagen I and collagen III were increased in FGR pregnancies. There were no differences in mRNA expression of collagen XIV or decorin.

CONCLUSION

Increased mRNA expression of collagen I and III, but not collagen XIV or decorin, is found in the umbilical arteries of preterm FGR pregnancies.

Single umbilical artery: What does it mean for the fetus? A case-control analysis of pathologically ascertained cases

PURPOSE

To ascertain the frequency of chromosomal and other anomalies in fetuses with single umbilical artery.

METHODS

Placentas with single umbilical artery were identified from hospital pathology laboratory records. For each identified case, the next consecutive placenta with two umbilical arteries served as a control. Pathology records, maternal histories, and prenatal ultrasounds when available were reviewed for congenital anomalies, pregnancy complications, and maternal characteristics. When indicated, placental specimens, amniocytes, or neonatal bloods were karyotyped.

RESULTS

Single umbilical artery existed in 2.0% (97/4846) of pathological specimens. Fetuses with single umbilical artery had significantly more chromosomal (10.3% vs. 1.0%) and other congenital anomalies (27% vs. 8%).

CONCLUSIONS

The high incidence of major chromosomal and congenital anomalies justifies detailed fetal ultrasonography, echocardiography, and amniocentesis for karyotype when single umbilical artery is discovered during routine ultrasound.

Hyrtl's anastomosis is normally developed in placentas from small for gestational age infants

BACKGROUND

The aim of this study was to investigate the occurrence and appearance of the anastomosis between the two umbilical arteries in placentas from infants small for gestational age (SGA).

METHODS

The arterial systems of 64 placentas from singleton pregnancies resulting in SGA infants were visualized by angiography. The method allowed study of the anastomosis between the umbilical arteries and calculation of the relative placental area supplied by each artery. The results were compared with findings in a previous study of appropriate for gestational age (AGA) infants. One-way analysis of variance (ANOVA) and chi2-analyses were used for statistics.

RESULTS

In 56 placentas the anastomosis was represented by a true vessel, in two by a fenestration, and in another two cases by fusion of the umbilical arteries. The anastomosis was absent in one case and another three cases had a single umbilical artery (SUA). When the diameter of the anastomosis was thinner than that of the umbilical arteries, their supply areas were significantly (p < or = 0.001) more symmetrical than in cases with a wider anastomosis. The anatomy of the anastomosis and the relationship between its width and the symmetry between the supply areas of each umbilical artery did not differ in placentas from SGA and AGA infants, despite various types of cord insertion and placentation.

CONCLUSION

Static measurements of Hyrtl's anastomosis do not indicate a contributing part for intrauterine growth retardation.

[Morphometric analysis of the blood-placental barrier in pregnant women with hypertension]

OBJECTIVES

About 10% women have hypertension in pregnancy. It is a serious threat to their health. It is considered one of the most important reasons for perinatal mortality foetuses and newborns.

DESIGN

The study deals with morphometric analysis of the blood-placental barrier in pregnant women with hypertension.

MATERIAL AND METHOD

The study group consisted of 105 pregnant women who gave birth in the Institute of Gynaecology and Obstetrics of Medical University of Gdańsk in 1995-1999. Patients were divided into two groups: first group (control) of 52 patients with uncomplicated pregnancies, the second -53 patients with pregnancies complicated with hypertension. The number of epithelial plates in 1 mm2 and the number of vessels in terminal villi were counted. The area, perimeter and diameters of terminal villi, length, thickness and area of thin epithelial plate, area of the blood vessel were estimated.

RESULTS

There was observed difference in the essential parameters for low-molecular metabolic exchange in placenta. The epithelial plate in pregnancy complicated with hypertension was thicker and shorter in relation to villi's circumference and its number in 1 villi and in 1 mm2 smaller. It decreases the exchange surface in plate in 40% in relation to the control group.

CONCLUSIONS

It is important that terminal villi reveal morphometric features of placenta on earlier stages (of pregnancy), i.e. a lower number of epithelial plates in terminal villi, a lower number of plates in 1 mm2 and the presence of short and thicker plates on the outer edges of villi.

[Morphometric indices of the altered feto-placental flow through the blood-placental barrier in pregnant women with hypertension]

OBJECTIVES

In a pregnancy complicated with hypertension, blood flow analysis in the artery allows us to foresee threat to the fetus. Abnormal blood flow in umbilical artery makes it possible to discover vascular changes in the placenta which can endanger the life of the fetus. DESIGN IN THIS STUDY: I tried to find possible correlations between quality indices of blood flow in the foetal umbilical artery evaluated in Doppler USG in pregnancies complicated with hypertension and parameters of low molecular exchange.

MATERIAL AND METHODS

53 pregnancies complicated with hypertension were selected for evaluation. On basis of the result of umbilical artery flow, patients were divided into two groups: first group of 35 patients with normal values of foeto-placental flow, the second--18 patients with abnormal results of foeto-placental flow out of whom 2 were diagnosed with absence of end-diastolic blood flow. The number of epithelial plates, the number of epithelial plates in 1 mm2 and number of vessels in terminal villi were counted. The area, perimeter and diameters of terminal villi, length, thickness and area of thin epithelial plate, area of the blood vessel were estimated.

RESULTS

The morphometric analysis indicates that the quality of the foeto-placental blood flow in pregnant women with hypertension results in parameters of the filtration area in terminal villi. In cases of complicated foeto-placental blood flow, thicker blood-placental barrier i.e. epithelial plate was found.

CONCLUSIONS

The results of our study indicate that the quality of feto-placental flow in pregnant women with hypertension results in parameters of the filtration area in terminal villi. In cases of complicated feto-placental blood flow a thicker blood-placental barrier i.e. epithelial plate was found.

Is the sampling site along the umbilical artery significant?

The purpose of umbilical blood sampling is to obtain accurate reflection of fetal acid-base status at birth. The site along the umbilical artery from which blood should be sampled postpartum was not specified. We evaluated if blood gases and pH values from three sampling sites along the umbilical artery are different. After defining the range of intraobserver (method) variability, blood pO(2), pCO(2), and pH were directly determined. The data showed consistent and significant increases in arterial pH and pCO(2) values and decreases in pO(2) values from near the fetal cord insertion to the placenta. The largest difference was noted between the fetal site and the placental plate and the smallest between the site near the placental cord insertion and the placental plate. We conclude that the site of cord blood sampling should be standardized and the umbilical artery should be sampled at a site nearest to the neonate.

Absent end diastolic flow in umbilical artery and umbilical cord thrombosis at term of pregnancy

BACKGROUND

Meconium staining of the fetus and placenta is associated with increased neonatal mortality and asphyxia. Very often it is unclear whether the discharge of meconium is a cause or an effect of fetal distress. In the available literature there are no large epidemiological studies of pregnancy outcome with meconium-related lesions, even though this could be useful to improve our state of knowledge on this topic.

CASE REPORT

A case of umbilical cord vascular necrosis is described. A severely asphyxiated infant was delivered at 39 weeks' gestation by cesarean section due to alarming results of fetal heart rate monitoring and rupture of membranes with meconium-stained amniotic fluid. There was no meconium aspiration. We report a review of 15 similar cases. In the whole series, a linkage between umbilical cord vascular necrosis and evidence of remote meconium discharge always seems to be detectable. The pathophysiological mechanism is unknown.

CONCLUSIONS

It is still not clear why only a tiny percentage of cases with meconium-stained amniotic fluid develops umbilical cord lesions and poor pregnancy outcome. Further investigations are needed to explain why some meconium-stained newborns suffer severe neurological and other damage even without meconium aspiration.

Umbilical artery aneurysm: prenatal identification in three fetuses with trisomy 18

Aneurysm of the umbilical artery is an extremely rare anomaly of the umbilical cord, with only two cases being documented in the English language literature. We report three cases diagnosed prenatally by ultrasound in the third trimester, all associated with single umbilical artery and multiple structural fetal anomalies. Prenatal karyotyping revealed trisomy 18 in all three cases. Umbilical cord anomalies, although rare, are associated with significant fetal morbidity and mortality. This report identifies umbilical artery aneurysm as an additional prenatal feature of trisomy 18.

Fused umbilical arteries near placental cord insertion

OBJECTIVE

This study was undertaken to study the frequency and cause of fused umbilical arteries (FUAs).

STUDY DESIGN

Umbilical cord on the placental side was carefully examined for FUAs by continuous interval sections.

RESULTS

The frequency was 3.1% or 22 in 702 infants with the frequency in female infants of 4.1% being significantly higher than that in male infants of 2.0%. The mean distance of fused points was 2.3 +/- 1.6 cm from placental cord insertion. Five of 22 cases showed both arterial fusion and division in the same umbilical cord. Marginal and velamentous insertions were significantly associated with FUAs. Gestational age, birth weight, and placental weight of 22 cases were within normal range.

CONCLUSION

Single umbilical artery should be confirmed by 2 or 3 sections of umbilical cord because of the high frequency of FUA on the placental side.