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Objective: The aims of the study were to establish reference ranges for placental length and thickness in a low-risk obstetric population and to assess the likelihood of a small for gestational age (SGA) neonate on the basis of placental length at 18-24 weeks' gestation., Methods: Placental length and thickness were measured by two sonographers in 520 singleton pregnancies. Uterine artery Doppler studies and a placental morphological assessment were also performed. Placental size was correlated with the birthweight centiles at delivery., Results: A placental length <10th centile between the gestational age of 18 and 24 weeks is a significant factor associated with SGA neonate [odds ratio (OR) = 2.8, 95% CL, 1.1-6.9]. An abnormal uterine artery Doppler is a significant factor for SGA neonate (OR = 3.4, 95% CL, 1.6-7.4). There was a weak relationship between cord insertion <2 cm from the placental margin and an SGA neonate (OR = 1.8, 95% CL, 0.4-8.2)., Conclusion: We have provided reference ranges for placental length and thickness from 18 to 24 weeks' gestation. A single measurement of placental length incorporated into the anatomy scan may assist in the early detection of a group at risk of delivering an SGA neonate., (© 2012 John Wiley & Sons, Ltd.)

The umbilical cord is the only communication between the fetus and the placenta and, not surprisingly, lesions or conditions affecting it may have detrimental effects in both. One important feature of the umbilical cord is its coiling index (UCI), with hypo- and hypercoiling being associated with fetal thrombotic vasculopathy, intolerance of labor, intrauterine growth restriction, cord stricture, thrombosis of cord and chorionic blood vessels, and fetal demise. It is essential that every placenta report include the UCI. The UCI could also be assessed prenatally, but there is currently no way of accurately assessing the entire length of the umbilical cord. The aim of this study was to compare UCI measured in a segment of cord 10 cm long (UCI-10) and over its total length (UCI-T). One hundred fifty consecutive placenta reports in which both measurements were recorded were retrieved from the files and analyzed. Gestational age ranged from 16 to 42 weeks, with a mean of 33.67 ± 5.96 weeks and a median of 36 weeks. Mean UCI-10 was 0.4360 ± 0.2625 coils/cm and mean UCI-T was 0.3530 ± 0.2022 coils/cm; the difference between these measurements was highly statistically significant (P < 0.0001). Counting the number of umbilical cord coils in 10 cm led to an overestimation of the UCI-T by 23.5%; it can be concluded, therefore, that the latter should be used.

The objective was to determine the cross-sectional area of the umbilical cord, its diameter and the diameter of its vessels to establish a reference curve for these parameters during pregnancy, through a prospective cross-sectional study, including 2,310 low-risk pregnancies between 12 and 40 weeks' gestation. Means and standard deviations (SDs), plus the 10th, 50th and 90th percentiles for each measurement were calculated using polynomial regression analysis. Mann-Whitney, Kruskal-Wallis and Wilcoxon tests were used for statistical analysis. These parameters increased significantly with gestational age. The area of the cord also varied significantly with parity. Their new reference curves for low risk pregnancies were calculated using polynomial regression, and an almost linear increase in values was found up to 32 weeks of pregnancy, tending to stabilise from then onwards. The regression equation of the umbilical cord area according to gestational age (GA) was: -1.417 + 0.3026*GA-0.008*GA(2) + 0.000007*GA(3) and the degree of adjustment (R(2)) was 0.89.

Background: To build a reference curve for the area of Wharton's jelly (WJ) in low-risk pregnancies from 13 to 40 weeks and to assess its relationship with estimated fetal weight (EFW)., Methods: 2,189 low-risk pregnancies had the area of WJ estimated by ultrasound and the 10th, 50th and 90th percentiles calculated using a third-degree polynomial regression procedure. EFW by ultrasound was correlated with the measurement of the area of WJ., Results: The area of WJ increased according to gestational age (R² = 0.64), stabilizing from the 32nd week onwards. There was a significant linear correlation between area of WJ and EFW up to 26 weeks (R = 0.782) and after that 5t remained practically constant (R = 0.047)., Conclusion: The area of WJ increases according to gestational age, with a trend to stabilize at around 32 weeks of gestation. It is also linearly correlated with EFW only up to 26 weeks of gestation.

Sensitivity of chorionic plate arteries to angiotensin II (AngII) is greatest at the placental periphery. Angiotensin converting enzyme (ACE) is central to the synthesis of AngII and is present in the placental vasculature. We measured vascular ACE activity/mg protein at 8-9 sites between the cord insertion and the periphery in 12 term placentae from normotensive, vaginally-delivered women. ACE increased from insertion to the periphery (P = 0.015); median ACE for each placenta was positively correlated with placental weight (P < 0.05) and placental:birthweight ratio (P < 0.02). We speculate that this may be related to fetal programming since placental:birthweight ratio is related to long-term health., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

Background: Non-central cord insertion has been associated with diminished chorionic vascular distribution in singleton placentas. The choriovascular correlates of peripheral cord insertion in diamniotic-monochorionic twin placentas remain undetermined., Aim: To study the association between type of cord insertion and choriovascular distribution of both twin territories in diamniotic-monochorionic twin placentas., Design: A prospective cohort of 138 monochorionic placentas was examined at Women and Infants Hospital between 2009 and early 2011. Thirty-five cases (25%), including disrupted placentas, placentas from higher order multiples and placentas from pregnancies complicated by twin-to-twin transfusion syndrome, were excluded. The correlation between cord insertion type and superficial choriovascular distribution was studied in the remaining 103 dye-injected diamniotic-monochorionic placentas. Cord insertion was categorized as paracentral, marginal or velamentous. The choriovascular distribution of each individual twin territory was assessed by analysis of number and density (number per surface area) of perforating chorionic arteries (PCA)., Results: In contrast with singleton placentas, there was no correlation between cord insertion type and a twin's own choriovascular distribution in diamniotic-monochorionic placentas. However, a strong correlation was found between the choriovascular distribution of one twin and the cord insertion type of the opposite twin. For a twin with paracentral or marginal cord insertion, the PCA density was significantly higher if the co-twin had a velamentous cord insertion than if the co-twin had a paracentral cord insertion (P < 0.001 and P < 0.05, respectively). Similarly, the PCA density of a twin with velamentous cord insertion tended to be higher if the co-twin had a velamentous, rather than paracentral cord insertion (P = 0.09)., Conclusions: This is the first study to suggest that in diamniotic-monochorionic twin gestations, the choriovascular architecture correlates with the cord insertion type of the co-twin. In general, velamentous cord insertion is associated with expanded choriovascular distribution in the opposite twin territory. Our observations may reflect novel manifestations of twin interdependence in monochorionic pregnancies., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

Objective: The purpose of this study was to evaluate the impact of noncentral placental cord insertion on birthweight discordance in twins., Study Design: We performed a multicenter, prospective trial of twin pregnancies. Placental cord insertion was documented as central, marginal, or velamentous according to a defined protocol. Association of the placental cord insertion site with chorionicity, birthweight discordance, and growth restriction were assessed., Results: Eight hundred sixteen twin pairs were evaluated; 165 pairs were monochorionic, and 651 pairs were dichorionic. Monochorionic twins had higher rates of marginal (P = .0068) and velamentous (P < .0001) placental cord insertion. Noncentral placental cord insertion was more frequent in smaller twins of discordant pairs than control pairs (29.8% vs 19.1%; P = .004). Velamentous placental cord insertion in monochorionic twins was associated significantly with birthweight discordance (odds ratio, 3.5; 95% confidence interval, 1.3-9.4) and growth restriction (odds ratio, 4; 95% confidence interval, 1.1-14.3)., Conclusion: Noncentral placental cord insertion contributes to birthweight discordance in monochorionic twin pregnancies. Sonographic delineation of placental cord insertion may be of value in antenatal assessment of twin pregnancies., (Copyright © 2011 Mosby, Inc. All rights reserved.)

Background: Umbilical cords of fetuses in breech presentation differ in length and coiling from their cephalic counterparts and it might be hypothesised that these cord characteristics may in turn affect ECV outcome., Aim: To investigate the relation between umbilical cord characteristics and the outcome of external cephalic version (ECV)., Study Design: Prospective cohort study., Subjects: Women (>35 weeks gestation) with a singleton fetus in breech presentation, suitable for external cephalic version. Demographic, lifestyle and obstetrical parameters were assessed at intake. ECV success was based on cephalic presentation on ultrasound post-ECV. Umbilical cord length (UCL) and umbilical coiling index (UCI) were measured after birth., Outcome Measure: The relation between umbilical cord characteristics (cord length and coiling) and the success of external cephalic version., Results: ECV success rate was overall 79/146 (54%), for multiparas 37/46(80%) and for nulliparas 42/100 (42%). Multiple logistic regression showed that UCL (OR: 1.04, CI: 1.01-1.07), nulliparity (OR: 0.20, CI: 0.08-0.51), frank breech (OR: 0.37, 95% CI: 0.15-0.90), body mass index (OR: 0.85, CI: 0.76-0.95), placenta anterior (OR: 0.27, CI: 0.12-0.63) and birth weight (OR: 1.002, CI: 1.001-1.003) were all independently related to ECV success., Conclusions: Umbilical cord length is independently related to the outcome of ECV, whereas umbilical coiling index is not., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

Objective: To determine the possible protective effects of Wharton's jelly (WJ) in umbilical cord and fetal growth by investigating the relationship between the amount of WJ and fetal birth weight., Materials and Methods: This study enrolled 299 women who delivered after an uneventful pregnancy. After separation of the placenta, a 5cm long section of umbilical cord was removed by scalpel. The weight of the cord section; the weight, volume, and density of its WJ; and the weight of the newborn and placenta were measured., Results: A significant positive correlation was found between WJ quantity, birth weight (p=0.002), and placental weight (p=0.003), whereas a significant negative correlation was observed for WJ density, fetal growth (p=0.035), and placental growth (p=0.002). WJ density was 1.63 ± 0.27g/mL. No significant correlation was found between the amount of WJ and weight gained during pregnancy (p=0.274) or maternal age (p=0.220)., Conclusion: As the amount of WJ increases, fetal weight increases. Accordingly, the amount of WJ might be a factor that influences fetal growth., (Copyright © 2011. Published by Elsevier B.V.)

Background: The position of the placental cord insertion, its shape and cord coiling are thought to be associated with perinatal outcome. This study derives indices describing the relationship of cord insertion to the placental centre, the shape of the placenta and cord coiling in placentas from unselected term pregnancies. Further, we investigate these indices in pregnancies affected by pre-eclampsia (PET), pregnancy induced hypertension (PIH), gestational diabetes mellitus (GDM) and delivery of a small for gestational age (SGA) baby., Design/methodology: Eight hundred and sixty one unselected women with singleton pregnancy delivering at 37-42 weeks were prospectively recruited to this study. Placental axes and their relationship with the cord insertion were measured using digital photography and proprietary software. From these, the cord centrality (distance of umbilical cord insertion from the centre) and placental eccentricity (deviation of the placental shape from circular) were derived. The cord coiling index (number of coils in the cord divided by the length of cord in cm) was also calculated from manual measurements., Results: The mean value of cord centrality index was 0.36 (SD = 0.21) and of placental eccentricity 0.49 (SD = 0.17). Left direction of umbilical cord coiling was more common than right (79% vs 16.4%) The mean cord coiling index was 0.20 (SD = 0.09) coils/cm. The indices were constant between 37 and 42 weeks and were no different in the non-affected population compared to women with pre-eclampsia (n = 17), PIH, (n = 27), GDM (n = 38) or delivery of an SGA baby (n = 54)., Conclusion: The cord centrality index that we derive suggests that the cord insertion is most commonly 'off centre', and eccentricity index that the placental shape is elliptical. Therefore, contrary to widely held belief, the cord does not normally insert centrally nor is the placenta normally round in shape. There is a preponderance of left sided coiling. There was no difference for any of the indices between the non-affected pregnancies and pregnancies affected by pre-eclampsia, PIH, GDM and SGA., (Copyright © 2010 Elsevier Ltd. All rights reserved.)

Unlabelled: Twin pregnancies are regarded as high risk pregnancies. It results from the possibility of occurrence of numerous complications both like the ones in singleton pregnancies and those characteristic for multiple pregnancy only. The complication occurring exclusively in multiple pregnancies is discordant intrauterine growth of the fetuses., The Aim: a response to the question if there a relationship between the type of afterbirth and twin birth weight discordance., Material and Methods: Material of the research consisted of 186 afterbirths derived from successful twin pregnancies. In the study the following were taken into consideration: evaluation of placenta/placentas types (mono- or dichorionic), place of umbilical cords insertion, and differences concerning birth weight of newborns., Results: The birth weight discordance of less than 10% (l0) in the twins was noted in 52.7% of pregnancies (n=98), discordance of 10-20% (II degree) was observed in 30.1% (n=56), and over 20% (III degree) in 17.2% (n=32). The birth weight discordance of the third degree was observed significantly more often in dichorionic diamniotic pregnancies with fused placentas. The discordance of third degree (>20%) occurred in 38.2% of female-male pairs, in 35.7% of female-female ones and in 24.3% of male-male pairs. In case of coexistence of both normal umbilical cord insertions the birth weight discordance of third degree occurred in 17.8% of pregnancies, in case of co-occurrence of the abnormal insertion with the normal one--in 21.8% of cases, and in case of the two abnormal insertions--in 10.5%. No statistically significant differences were found., Conclusions: There is a relationship between the type of afterbirth and birth weight in twins. The largest birth weight discordance between fetuses occurs in the following cases: in dichorionic pregnancies with fused placental discs, in case of co-existence of abnormal and normal umbilical cord insertions and in female-male pair of twins.

The most significant anatomical structure of the umbilical cord is its level of coiling. The coiled geometry of the umbilical cord largely affects umbilical blood flow that is vital for fetus's well-being and normal development. In this study, we developed a computational model of steady blood flow through the coiled structure of an umbilical artery. The results showed that the driving pressure for a given blood flow rate is increasing as the number of coils in cord structure increases. The driving gradient pressures also vary with the pitch that dictates the coils' spreading. The coiled structure is resulting in interwoven streamlines along the helix and wall shear stresses (WSS) with significant spatial gradients along the cross-sectional perimeter anywhere within the helical coil. These gradients may have an adverse effect on the development of the fetus cardiovascular system in cases with over coiling (OC) or under coiling (UC) characteristics. The number of coils does not affect the distribution and levels of WSS. However, when the coils are more spread (eg, larger pitch number), the maximal WSS is significantly smaller. Cases with twisted and OC cords seem to yield very large values and gradients of WSS, which may place the fetus into high risk of abnormal development.

Goals: Fetal growth depends on placental growth; the fetoplacental weight ratio (FPR) is a common proxy for the balance between fetal and placental growth. Male and female infants are known to have differing vulnerabilities in fetal life, during parturition and in infancy. We hypothesized that these differences may be paralleled by differences in how birth weight (BW) and the fetoplacental weight ratio (FPR) are affected by changes in placental proportions., Materials and Methods: Placental proportion measures (disk shape, larger and smaller chorionic diameters, chorionic plate area calculated as the area of an ellipse with the 2 given diameters, disk thickness, cord eccentricity and cord length) were available for 24,601 participants in the Collaborative Perinatal Project delivered between >34 and <43 completed weeks. The variables were standardized and entered into multiple automated regression splines (MARS 2.0, Salford Systems, Vista CA) to identify nonlinearities in the relationships of placental growth measures to BW and FPR with results compared for male and female infants., Results: Changes in chorionic plate growth in female compared to male infants resulted in a greater change in BW and FPR. The positive effects of umbilical cord length on BW reversed at the mean umbilical cord length in females and at +0.08 SD in male infants., Conclusions: Female infants' BW and FPR are each more responsive to changes in placental chorionic plate growth dimensions than males; this may account for greater female resilience (and greater male vulnerability) to gestational stressors. The effect of umbilical cord length on FPR may be due to longer cords carrying greater fetal vascular resistance. Again male fetuses show a higher "threshold" to the negative effects of longer cords on FPR.

Objective: To determine bovine fetal characteristics significantly associated with increasing gestational age as measured via transcutaneous ultrasonography over the right flank., Methods: The length of gestation at date of pregnancy diagnosis via transcutaneous and transrectal ultrasonography was determined for 224 dairy cattle by estimation from subsequent calving dates. A separate dataset was created for each measurable fetal characteristic (i.e. thoracic diameter, abdominal diameter, umbilical diameter, placentome length and placentome height) and risk factors significantly associated with gestational age at pregnancy diagnosis within each dataset, including the fetal characteristic, were identified., Results: Abdominal diameter was the most frequently observed fetal characteristic and thoracic diameter was the least. Gestational age at pregnancy diagnosis (d) was significantly associated with fetal thoracic diameter (P < 0.01), abdominal diameter (P < 0.01) and umbilical diameter (P = 0.02) when measured via transcutaneous ultrasound. Within each model, sire breed, dam breed, dam age and/or calf sex were also significantly associated with gestational age. Gestational age at pregnancy diagnosis was not significantly associated with either placentome height or length (P > 0.05)., Conclusion: Fetal thoracic diameter, abdominal diameter and umbilical diameter were found to be significantly associated with gestational age between approximate days 73 to 190 of gestation. Transcutaneous ultrasonography may prove a useful method of estimating gestational age in the absence of accurate breeding records.

Objective: Activity has been demonstrated in promoting bone mass in infants and adults. One of the major signs of fetal activity may be the length of the umbilical cord. We hypothesized that the fetus with a shortened umbilical cord may have low bone mineralization because of decreased movement or activity., Study Design: We investigated eight healthy term infants with shortened umbilical cords and 15 control term infants. Mothers with pre-eclampsia or hypertension, chorioamnionitis or prolonged ruptured of membranes were excluded from the study. Mother's age, parity, infants' gender, and birth and placenta weights were recorded. The umbilical cord length and diameter were measured as well as the newborn's tibial speed of sound (SOS). SOS measurements (Sunlight Omnisense 7000P instrument) were obtained at the tibial midshaft., Results: Measurement reproducibility was 0.8+/-0.6% (mean+/-s.d.) for repeat SOS measures. There were no differences between the two groups in mother's age (24.6+/-5.8 vs 25.8+/-3.3 years), parity (2+/-1 vs 2+/-1), infant's gender (25% females vs 47% females), birth weights (3320+/-451 vs 3409+/-452 g), or placental weights (521+/-69 vs 588+/-105 g). Umbilical cord diameters were also similar, 1.1+/-0.3 vs 1.1+/-0.2 cm. However, there was a difference in the cord length between the two groups, 46+/-2 vs 57+/-4 cm (Mann-Whitney, P<0.001). The newborn infants with the shorter umbilical cord also had lower tibial SOS compared with controls, 3047+/-107 vs 3194+/-311 m/sec (Mann-Whitney, P<0.05). Tibial SOS was related to the infant's umbilical cord length (r=0.57, P<0.01) but not to infant's birth weight, gender, umbilical cord diameter, maternal age, or placenta weight., Conclusion: Infants with a short umbilical cord length have lower bone strength.

The umbilical cord and its constituent tissues: an outer layer of amnion, porous Wharton's jelly, two umbilical arteries, and one umbilical vein, are designed to protect blood flow to the fetus during a term pregnancy. The outer amnion layer may regulate fluid pressure within the umbilical cord. The porous, fluid filled Wharton's jelly likely acts to prevent compression of the vessels. Blood flow is regulated by smooth muscle surrounding the arteries that is intermingled with a collagen based extracellular matrix (ECM). Doppler ultrasound measurements of blood flow within the umbilical cord, and at specific sites within the developing fetus, provide evidence of impaired blood flow in conditions such as preeclampsia. Mechanosensory communication between cells and the extracellular matrix (ECM) may likely result in cords possessing abnormal physical dimensions, impaired hemodynamics, and altered composition within the umbilical cord tissues. Few studies have explored the biomechanics of the intact umbilical cord, with its constituent tissues, from normal pregnancies or abnormal pregnancies, maternal or fetal complications. Here, alterations in the umbilical cord are reviewed concerning anatomical abnormalities, disease, or chromosomal alterations using sonography, Doppler ultrasound, histology, and biomolecular and biochemical analyses. This paper considers how current knowledge of the umbilical cord and its constituent tissues can be used to infer biomechanical function. In addition, the mechanical consequences of structural abnormalities and altered tissue structure or composition are discussed with a specific focus on preeclampsia.

Objectives: To investigate the association between the amount of Wharton's jelly (WJ) and the umbilical coiling index (UCI)., Methods: The subjects included 140 pregnant women in the 2nd or 3rd trimester. The antenatal UCI was calculated as the reciprocal of the distance between a pair of coils. The sonographic cross-sectional areas of the cord, arteries and vein were measured. The WJ area was calculated by subtracting areas of the total vessels from the cord., Results: UCIs were significantly smaller and WJ areas were significantly greater in the 3rd trimester than in the 2nd trimester. No correlations were observed between the UCI and WJ area in both trimesters., Conclusion: There is a reduction of the UCI during pregnancy. No direct correlations were found between the amount of WJ and UCI.

Objective: To compare selected umbilical cord parameters, especially cord coiling, between breech and vertex presentations., Methods: We prospectively collected umbilical cords from uncomplicated breech and vertex obtained during elective term cesarean deliveries. We compared various cord parameters between the two groups as well as data regarding obstetric history and pregnancy outcome., Results: We evaluated 55 umbilical cords from breech and 55 from vertex deliveries. Umbilical cord length (56.93 cm vs. 63.95 cm, P=0.05), number of coils (5.1+/-0.4 vs. 11.7+/-0.6, P<0.0001) and umbilical cord index (UCI) (0.09 coils/cm vs. 0.18 coils/cm, P<0.0001) were all significantly lower for breech presentations and remained significant following multivariate analysis., Conclusion: We document significant differences in umbilical coiling and the UCI between breech and vertex presentation. The precise reason for these differences is still unclear.

To study placental characteristics in relation to perinatal outcome in 150 pairs of monochorionic diamniotic (MCDA) twins. Between January 1998 and January 2007 150 pairs of MCDA twins were delivered in the University Medical Center, Utrecht, The Netherlands. Mortality, neonatal morbidity and birth weight discordancy were studied in relation to type of anastomoses, type and distance between cord insertions and placental sharing. From 14 weeks onwards, there were 45 (15.0%) perinatal deaths. We found no clear relationship between perinatal mortality and type of anastomoses, distance between cord insertions and placental sharing. Perinatal mortality was significantly increased in the presence of velamentous cord insertion (OR 3.65, 95% CI 1.83-7.28). Data concerning neonatal morbidity were similar. TTTS occurred predominantly in the presence of AV-anastomoses without compensating superficial AA-anastomoses (p=0.005) and occurred more frequently in the presence of velamentous cord insertion (OR 1.79, 95% CI 0.94-3.44). Twins with unequal shared placentas had significantly more often severe birth weight discordancy, although only in the presence of AA-anastomoses (OR 4.09, 95% CI 1.74-9.63). If AA-anastomoses were absent in the unequally shared placenta, there was no relation between severe birth weight discordancy and unequal sharing of the placenta (OR 1.06, 95% CI 0.08-13.52). In MCDA twins, placental characteristics determine perinatal outcome, occurrence of TTTS and fetal growth. Prenatal identification of these characteristics by ultrasound may alter counselling and intensity of pregnancy surveillance.

This study was designed to establish the morphological features of the placenta of the Martina Franca jenny. Ten placentas were harvested at the time of foal delivery and examined both for gross and histological characteristics. The following factors were determined: the total weight and volume of the placenta and its components, the surface area of the allantochorion, umbilical cord length and site of insertion, and the diameter of the umbilical cord vessels and vascular pattern type. The weight of the placenta was similar to previously reported for ponies, and represented 12% of foal birth weight. Umbilical cord length was similar to that in the horse but longer than in the pony, while cord weight was intermediate between the two. In a histological examination, numerous strong villi were observed at sites corresponding to the non-pregnant and pregnant horn and uterine body. No villi were detected in the area overlying the cervical star. Despite obvious similarities between the donkey and horse placenta, specific morphological features do exist, and are possibly related to the differences in length of gestation.

Our previous study reported that TGF-beta may be isolated from human Wharton's jelly (WJ) in a form of soluble, high molecular complex(es). We decided to study the effect of extracellular matrix degradation and reduction of disulphide bridges reduction on the release of TGF-beta from WJ. The WJ prepared from the umbilical cords of newborns delivered at term by healthy mothers was homogenised and treated with hyaluronidase, collagenase, heparinase, chondroitinase and beta-mercaptoethanol, the resulting extracts were then submitted to TGF-beta immunoassay and SDS/PAGE followed by Western immunoblotting. The effect of metalloproteinase activation on TGF-beta was also studied. Pre-treatment of WJ homogenates with hyaluronidase or collagenase markedly increased the extractability of TGF-beta, but did not dissociate the complexes. In contrast, the action of beta-mercaptoethanol resulted in the release of free TGF-beta; but activation of metalloproteinases resulted in the disappearance of this factor. We conclude that TGF-beta1 is bound through disulphide bonds to an extracellular matrix component of WJ. The large amount of collagen fibrils and hyaluronate molecules which surround the cells scattered in WJ may prevent the access of extracting solution to TGF-beta causing a low extractability of this factor. Although hyaluronate and collagen do not bind TGF-beta directly, they may present a barrier that prevents the diffusion of TGF-beta in WJ and results in its concentration around the cells thereby facilitating its interaction with membrane receptors and subsequent stimulation of cell division and synthesis of extracellular matrix components.

Objectives: To study the association between thickness of the umbilical cord at 11+0 to 14+6 gestational weeks and perinatal outcome., Methods: We studied 216 pregnant women between 11+0 and 14+6 weeks' gestation with singletons, intact membranes, normal volumes of amniotic fluid and a regular menstrual period. Patients with umbilical cord measurements below the 5(th) centile were defined as thin umbilical cord group and those between the 5(th) and 95(th) or above 95(th) centile were defined as non-lean umbilical cord group. Abortion or fetal demise, preeclampsia, mode of delivery, gestational age at delivery, birth weight, and 5-min Apgar scores were noted., Results: A statistically significant difference existed between the mean gestational age, mode of delivery, birth weight and adverse perinatal outcome of the two groups. The relative risk of the adverse perinatal outcome in lean umbilical cords was 6.92 (2.71-17.67; 95% CI). The umbilical cord thickness correlated with birth weight (P<0.05)., Conclusions: Sonographic finding of a lean umbilical cord at 11+0 to 14+6 weeks' gestation should prompt the physician to strict monitoring of pregnancy.

Approximately 40 years ago, Dr. Peter Dunn introduced a simple method to determine the insertion length of umbilical catheters in neonates, by using the 'shoulder-umbilical' (S-U) length. Since then, various studies have reported a high rate of malposition of umbilical catheters. One of the possible reasons is that the method used to determine the S-U length varies among paediatric professionals. We performed a questionnaire study among 101 paediatric professionals in the Netherlands and found that the method used by the participants to measure the S-U length was highly inconsistent. Placement of an umbilical venous catheter in a too deep position may lead to potentially life-threatening complications. Therefore, uniformity in measurement is paramount for clinical and teaching purposes. Paediatric professionals using Dunn's definition to place umbilical catheters should adhere more strictly to the original description of the measurement of the S-U length., ((c) 2008 S. Karger AG, Basel.)

Background: The objective of this study was to evaluate the capacity of the cross-sectional area and diameter of the umbilical cord, and the area of Wharton's jelly (WJ), to predict abnormalities in estimated fetal weight (EFW) in 20-40 week, low-risk pregnancies., Methods: A validation study was performed in 1,828 pregnant women. Fetal weight was estimated by ultrasonography and classified as: small for gestational age (SGA), appropriate for gestational age (AGA) or large for gestational age (LGA) according to the 10th and 90th percentiles of the reference curve. Measurements of the parameters of the cord were used to classify it as thin, normal or thick using the 10th and 90th percentiles of the reference curves as limits. The capacity of the diameter and total area of the cord and the area of WJ to predict abnormal EFW was calculated for different gestational ages., Results: The capacity of the diameter of thin cords to predict SGA fetuses (S =8.3%, PPV =16.5%) or thick cords to predict LGA fetuses (S =5.5%, PPV =30.1) was weak, similar to the capacity of the area of the umbilical cord to predict SGA (S =8.3%; PPV =16.3%) or LGA fetuses (S =5.5%; PPV =27.8%). The capacity of the area of WJ to predict SGA fetuses (S =5.7%, PPV =11.7%) was similar to its capacity to predict LGA fetuses (S =4%, PPV =27.1%)., Conclusion: Despite the correlation between the diameter and cross-sectional area of the cord and EFW, these measurements were not found to be useful in predicting alterations in EFW and should not be used for this purpose.

Normal fetal development is dependent on adequate placental blood perfusion. The functional role of the placenta takes place mainly in the capillary system; however, ultrasound imaging of fetal blood flow is commonly performed on the umbilical artery, or on its first branches over the chorionic plate. The objective of this study was to evaluate the structural organization of the feto-placental vasculature of the chorionic plate. Casting of the placental vasculature was performed on 15 full-term placentas using a dental polymer mixed with colored ink. Observations of the cast models revealed that the branching architecture of the chorionic vessel is a combination of dichotomous and monopodial patterns, where the first two to three generations are always of a dichotomous nature. Analysis of the daughter-to-mother diameter ratios in the chorionic vessels provided a maximum in the range of 0.6-0.8 for the dichotomous branches, whereas in monopodial branches it was in the range of 0.1-0.3. Similar to previous studies, this study reveals that the vasculature architecture is mostly monopodial for the marginal cord insertion and mostly dichotomous for the central insertion. The more marginal the umbilical cord insertion is on the chorionic plate, the more monopodial branching patterns are created to compensate the dichotomous pattern deficiency to perfuse peripheral placental territories.

To elucidate the morphological differences between placentas from normal and cloned cattle pregnancies reaching term, the umbilical cord, placentomes and interplacentomal region of the fetal membranes were examined macroscopically as well as by light and scanning electron microscopy. In pregnancies established by somatic nucleus transfer (NT), the umbilical cord and fetal membranes were edematous. Placentomal fusion was common, resulting in increased size and a decreased number of placentomes. Extensive areas of the chorioallantoic membrane were devoid of placentomes. An increased number of functional or accessory microcotyledons (<1 cm) were present at the maternally oriented surface of fetal membranes. Extensive areas of extravasated maternal blood were present within the placentomes and in the interplacentomal region. The crypts on the caruncular surface were dilated and accommodated complexes of more than one primary villus, as opposed to a single villus in non-cloned placentae. Scanning electron microscopy of blood vessel casts revealed that there was also more than one stem artery per villous tree and that the ramification of the vessels failed to form dense complexes of capillary loops and sinusoidal dilations as in normal pregnancies. At the materno-fetal interface, however, the trophoblast and uterine epithelium had normal histology. In conclusion, the NT placentas had a range of pathomorphological changes; this was likely associated with the poor clinical outcome of NT pregnancies.

A recent reassessment of the phylogenetic affinities of cetaceans makes it timely to compare their placentation with that of the artiodactyls. We studied the placentae of two sympatric species of dolphin from the Amazon River Basin, representing two distinct families. The umbilical cord branched to supply a bilobed allantoic sac. Small blood vessels and smooth muscle bundles were found within the stroma of the cord. Foci of squamous metaplasia occurred in the allanto-amnion and allantochorion. The interhemal membrane of the placenta was of the epitheliochorial type. Two different types of trophoblastic epithelium were seen. Most was of the simple columnar type and indented by fetal capillaries. However, there were also areolar regions with tall columnar trophoblast and these were more sparsely supplied with capillaries. The endometrium was well vascularised and richly supplied with actively secreting glands. These findings are consistent with the current view that Cetacea are nested within Artiodactyla as sister group to the hippopotamids.

The morphology of the neonatal umbilical cord was studied in 23 women during elective surgical delivery and in 32 women during normal physiological delivery. Organ- and histometric indices were used. These included: length, weight, a linear weight unit; the average diameter of the umbilical cord, etc. The significant increase of organometric indices (a linear weight unit of weight, the average diameter of the umbilical cord) and histometric ones (a drastic venous lumen increase, a significant increase in the proportion of Wharton's jelly) document acute umbilical blood flow disorder in the absence of the conditions characteristic for normal delivery. Moderately pronounced edema of the umbilical cord peripheral layer emerges. A complex of morphofunctional umbilical cord changes during surgical delivery serves as predictor of neonatal respiratory distress syndrome.

Objectives: To evaluate whether the antenatal umbilical coiling index (aUCI) as measured by ultrasonography predicts the postnatal umbilical coiling index (pUCI) and adverse pregnancy outcome., Methods: In a prospective study in 117 pregnancies, the aUCI was measured between 28 weeks and term by ultrasonography. The aUCI was calculated as the reciprocal value of the mean pitch of one complete coil. The pUCI was calculated as the number of coils divided by the cord length in cm. The correlation between aUCI and pUCI was assessed and likelihood ratios for adverse pregnancy outcome were calculated., Results: We had complete data on 81 subjects. Mean aUCI +/- SD was 0.30 +/- 0.09 and mean pUCI +/- SD was 0.17 +/- 0.08. The correlation coefficient between aUCI and pUCI was 0.66, P < 0.001. Limits of agreement were 0-0.28 coils/cm. The positive likelihood ratio for small-for-gestational-age infants was 2.6 (95% confidence interval (CI) 0.6-11.6) for ultrasound hypocoiling, and 5.7 (95% CI 1.3-24.8) for ultrasound hypercoiling. The positive likelihood ratio for interventional delivery for non-reassuring fetal status was 1.2 (95% CI 0.2-9.0) for ultrasound hypocoiling, and 10.3 (95% CI 2.1-50.2) for ultrasound hypercoiling., Conclusions: Strong correlation coefficients comparing the aUCI and pUCI do not reflect agreement. Since the limits of agreement were almost as wide as the full range for the pUCI, the aUCI does not predict the pUCI with sufficient precision. Larger prospective studies are required to confirm the predictive potential of the aUCI for adverse pregnancy outcome., (Copyright 2006 ISUOG. Published by John Wiley & Sons, Ltd.)

Objective: To evaluate whether a relationship exists between the antenatal umbilical coiling index (UCI) and umbilical cord Doppler flow characteristics., Methods: During the fetal anatomical survey in 200 consecutive pregnant patients at 18-23 weeks' gestation, we recorded umbilical coiling patterns and blood flow characteristics. The antenatal UCI, calculated as a reciprocal value of the distance between a pair of umbilical cord coils, was compared with Doppler parameters including umbilical vein blood flow volume (in mL/min/kg), and mean resistance index (RI) and peak systolic velocity (PSV in cm/s) averaged from both umbilical arteries., Results: A total of 154 patients met the inclusion criteria of singleton pregnancy and having adequate sonographic umbilical cord images, Doppler flow indices, and all demographic, antenatal and labor data. The mean antenatal UCI was 0.40, with 10th and 90th centiles of 0.20 and 0.60, respectively. The mean +/- SD umbilical artery RI and PSV and umbilical vein blood flow volume were 0.74 +/- 0.07, 25.1 +/- 6.4 cm/s, and 264 +/- 106 mL/min/kg, respectively. All Doppler variables correlated significantly with antenatal UCI, with lower RI and higher PSV and umbilical vein blood flow volume values being associated with higher antenatal UCI (P = 0.016, P < 0.001, and P = 0.032, respectively). However, when stratified by antenatal UCI into hyper- (above 90th centile), normo- (10th-90th centile), and hypocoiled (below 10th centile) umbilical cord groups, a significant difference was observed for PSV only (P = 0.016)., Conclusion: It appears that umbilical cord coiling modulates noticeably blood flow through the umbilical cord. We speculate that more prominent umbilical coiling (higher antenatal UCI values) has a protective effect on blood flow in terms of decreased arterial resistance and higher blood flow velocities, as well as increased venous blood flow. However, due to lack of significant differences between Doppler characteristics when stratified by antenatal UCI into hypo-, normo-, and hypercoiled groups, the clinical implications of this observation are uncertain., (Copyright 2006 ISUOG. Published by John Wiley & Sons, Ltd.)

We performed a retrospective review of the length of the umbilical cords of stillborn fetuses with renal agenesis, cystic kidneys, and bladder outlet obstruction and compared the cord length with normative data. Among the 41 cases, 31 had umbilical cord lengths that were shorter than average. However, the remaining 10 cases had an average to increased cord length. Urinary output in those cases might have been sufficient in early pregnancy to allow adequate fetal activity and sufficient umbilical cord lengthening. We suggest that the length of the umbilical cord can have implications relative to the developmental pathogenesis of some congenital urinary tract abnormalities.

Objective: To compare the umbilical cord diameter (UCD) in euploid and aneuploid fetuses at 11-14 weeks of gestation., Methods: In 299 fetuses at 11-14 weeks of gestation the UCD, the nuchal translucency and the a-wave of the ductus venosus were measured. Reference ranges for the UCD according to the gestational age and to the crown-rump-length (CRL) were obtained by measuring the UCD by outer-to-outer border of 244 singleton pregnancies with normal karyotype. The fetal karyotype was established by chorionic villus sampling, amniocentesis or in case of suspected chromosomal abnormalities in the newborn. Linear regression was used to determine the significance of the association between the UCD and CRL or gestational age., Results: Two hundred and ninety-nine fetuses were examined. The median fetal CRL was 64.5 mm (range 45-84) and the median gestational age was 13 (range 11-14) weeks. In the chromosomally normal group the UCD significantly increased with the CRL (r=0.620; p<0.001) and the gestational age (r=0.555; p<0.001). The regression equation for the mean UCD (y) according to the gestational days (x) was: y=-0.604+0.051*x. The regression equation for the mean UCD (y) according to the CRL (x) was: y=1.962+0.029*x. There were no significant differences in the mean UCD in fetuses without and with chromosomal abnormalities. The proportion of fetuses with an UCD above the 95th centile for CRL was higher in aneuploid compared to euploid fetuses (5/14 vs. 13/285, p<0.005). In 5/14 (35.7%) fetuses with chromosomal defects the NT and the UCD were above the 95th centile, whereas none of the fetuses with normal karyotype showed this combination. The proportion of fetuses with increased UCD and abnormal DV blood flow was increased in the cases with chromosomal abnormalities (33.3 vs. 1.8%, p<0.005)., Conclusion: Umbilical cord diameter at 11-14 weeks increases with fetal CRL. Fetuses with chromosomal abnormalities are more likely to have an UCD above the 95th centile. Therefore, sonographic evaluation of the umbilical cord during first trimester ultrasound might be of additional value in the assessment of fetuses at risk for aneuploidies., (Copyright (c) 2006 S. Karger AG, Basel.)

Introduction: Even though placentas from assisted reproduction programs often differ from placentas of women who conceived naturally, they are rarely examined. The aim of our investigation was to determine some gross characteristics of placentas of women who conceived with assisted reproduction., Material and Methods: We examined 30 placentas from an assisted reproduction program (20 from in vitro fertilization and 10 from intrauterine insemination) and 30 placentas of women who conceived naturally. All women were age matched. All the women were at term., Results: The mean weight of placentas from assisted reproduction program was 573 g and of those after natural conception--582.67g. The mean length of the umbilical cords was 64.3cm after assisted reproduction and 66.3cm after natural conception. The mean placenta thickness after assisted reproduction was 2,22 cm and after natural conception 2.28 cm. Eight placentas of the study group had a marginal insertion of the umbilical cord, which lead to a statistically significant difference when compared to placentas of women who conceived naturally: chi-square = 7.07; p>0.01., Discussion: Marginal cord insertion into the placenta after assisted reproduction is also often described in the literature (as a possible "consequence" of embryo-transfer)., Conclusion: There were no statistically significant differences in the mean weight and dimensions of placentas, length of the umbilical cord, gross pathological features of placentas and cords, mean birth weight of babies and placental/fetal ratios between women from assisted reproduction program and those who conceived naturally.

Fetal growth depends in part on placental growth. The authors tested placental measures derived from digital images for reliability and to evaluate their association with birth weight and gestational age. A total of 628 women recruited into the Pregnancy, Infection, and Nutrition Study, a prospective cohort study of preterm birth in central North Carolina between 2002 and 2004, delivered singleton liveborn infants after 24 completed weeks' gestation. Novel chorionic plate morphometric parameters captured off digital images of the gross placenta were analyzed as estimators of gestational age and birth weight. Without acknowledgment to placental weight, digitally obtained lateral chorionic plate growth measures accounted for 17 percent of gestational age variance and 35 percent of birth weight variance, overall. Chorionic plate measures accounted for 10 percent of birth weight variance beyond that accounted for by placental weight alone. Among preterm births, 34 percent of gestational age variance and 63 percent of birth weight variance were accounted for by lateral chorionic plate growth measures. Intraclass correlation coefficients for the novel digital measures ranged from 0.96 to 0.98. Reliable digital measures of lateral chorionic plate growth estimate birth weight variance more strongly than gestational age, project variance that is not accounted for by placental weight, and project these outcomes to a greater degree in preterm births than at term.

Objective: The purpose of this study was to evaluate a relationship between the umbilical cord thickness and cord coiling patterns during the fetal sonographic anatomic survey in the second trimester of pregnancy., Methods: This was a prospective study of 470 patients with singleton pregnancies who had a fetal anatomic survey with recorded umbilical coiling patterns between 18 and 23 weeks' gestation. The umbilical cord thickness was assessed as an umbilical diameter at the level of the fetal abdominal cord insertion and compared with the antenatal umbilical coiling index (aUCI), calculated as a reciprocal value of the distance between a pair of umbilical cord coils., Results: Three hundred twenty-one patients had adequate sonographic umbilical cord images and maternal demographic, antenatal, and labor data to meet inclusion criteria. The mean aUCI was 0.41 with 10th and 90th percentiles of 0.21 and 0.60, respectively. A total of 10.6% (34/321) and 9.3% (30/321) of patients were categorized as having hypocoiled and hypercoiled umbilical cords, respectively. The mean cord diameter +/- SD was 9.48 +/- 0.97 mm (range 7.0-12.5 mm). There was no statistically significant correlation between aUCI and umbilical cord thickness (P = .1164)., Conclusions: An aUCI, or umbilical coiling pattern, does not correlate with umbilical cord thickness. It appears that a lesser amount of the umbilical supportive tissue, mainly Wharton jelly, is not related to an increased umbilical cord coiling pattern.

Several recent publications have focused on the association between the occurrence of twin-to-twin transfusion syndrome (TTTS) in diamniotic-monochorionic twins and the presence of a number of selected anatomic placental characteristics (distribution of vascular territory, cord insertion, type and number of inter-twin anastomoses). In contrast, the potential importance of the vascular distribution patterns of the individual twins remains to be elucidated. Based on its gross architectural distribution pattern, chorionic vasculature is traditionally described as disperse, magistral or mixed. The aim of this study was (1) to determine the relative prevalence of these vascular distribution patterns in monochorionic twin placentas, and (2) to correlate these patterns with the presence of TTTS and known anatomic placental features linked to TTTS. The placentas of 89 consecutive diamniotic-monochorionic twins (15 with TTTS, 74 without TTTS), examined at Women and Infants Hospital, were studied. Disperse vascular patterns were seen in 53% of twins, and magistral or mixed patterns in 47%. The prevalence of magistral/mixed vascular patterns was significantly higher in TTTS gestations than in non-TTTS gestations (60% versus 44%, P<0.05) and, in TTTS gestations, much higher in donor twins than in recipient twins (87% versus 33%, P<0.005). A strong association was found between the presence of magistral/mixed patterns and marginal/velamentous cord insertion, low number of inter-twin anastomoses, and uneven distribution of the vascular territories. These findings suggest that the magistral/mixed vascular distribution pattern may represent an important placental architectural feature contributing to the complex pathophysiology of TTTS.

Vascular malformations cause discomfort and pain in children and are often associated with skeletal hypertrophy. Their molecular basis is poorly understood. Ephrin ligands and Eph receptor tyrosine kinases are involved in embryonic vascular development. In mice, some ephrin/Eph family members show a complementary expression pattern in blood vessels, with ephrinB2 being expressed on arterial and EphB4 on venous endothelium. Targeted deletions of the genes reveal their essential roles for conduit vessel development in mice, suggesting similar functions during human vascular development and deregulation in vascular malformations. Here, we have defined the expression patterns of human ephrinB2, EphB4, and EphB2 in normal vessels of neonates (i.e. umbilici) and adults and compared them with those in congenital venous malformations. In adults, normal vessels of the skin, muscle, and legs express ephrinB2 and EphB2 on arterial endothelial cells (ECs), whereas EphB4 is found in arteries and veins. In the umbilicus, EphB2 is a specific marker of arterial ECs, whereas ephrinB2 is additionally expressed in venous ECs, suggesting an arterial function of the veins. In venous malformations, the expression of EphB4 is not altered, but both ephrinB2 and EphB2 are ectopically expressed in venous ECs. This may reflect a nonphysiologic arterialization of malformed veins. Our study shows that the arterial markers ephrin B2 and EphB2 are expressed in a subset of veins, and it remains to be studied whether this is cause or consequence of an altered vascular identity.

Background: Umbilical vein constriction at the fetal abdominal inlet is a common finding after week 13, when the period of umbilical herniation is brought to an end., Aims: To test the hypothesis that a constricting umbilical ring within physiological ranges affects fetal hemodynamics by either pooling blood in the placenta or restricting nutrient transfer to the fetus and thus shift the birthweight/placental weight (BW/PW) ratio. A constriction could also cause pressure changes and elongation of the cord and possibly be a disadvantage during labour., Study Design: Cross-sectional., Subjects: 359 Low-risk singleton pregnancies at 13-40 weeks of gestation., Outcome Measures: Standard deviation score (z-score) and regression analysis were used to determine the effect of umbilical vein constriction (expressed by increased blood velocity) on birthweight/placental weight ratio (BW/PW), cord length, Apgar score and emergency delivery due to fetal distress., Results: Umbilical venous constriction had a mild but significant effect on BW/PW in male (p=0.018) but not in female fetuses. Increased constriction was also associated with increased length of the cord but only in female fetuses (p=0.019). Cord length was positively related to birthweight and placental weight, but an increased length of the cord was also associated with decreasing BW/PW ratio for the male fetuses only (p=0.044). Increasing degree of venous constriction was associated with Apgar score < or =7 at 1 (p=0.009) but not at 5 min after birth and was not associated with emergency delivery., Conclusion: Physiological umbilical venous constriction exerts a mild but significant gender-specific hemodynamic impact on intrauterine development.

Objective: To establish an umbilical cord thickness nomogram from anatomy ultrasound scans performed between 18 and 23 weeks of gestational age in singleton pregnancies, and compare it to two previously published nomograms., Material and Methods: In this retrospective cohort study of 1107 patients, a total of 650 singleton pregnancies were included. The umbilical cord diameter measurements were performed at the level of fetal abdominal wall insertion, and were correlated with gestational age (GA) and estimated fetal weight (EFW). Statistical analysis with non-parametric polynomial least squares regression analysis was performed., Results: A statistically significant correlation between umbilical cord diameter and GA (P<0001, r=0.399, 95% CI 0.331 to 0.464), and EFW (P<0001, r=0.420, 95% CI 0.353-0.483) was observed. A nomogram of umbilical cord thickness according to GA (y), and EFW (y'), was generated from the following equations:y=-51.30+5.367*x-0.1165*x(2) and y'=6.917+0.007233*x, respectively., Conclusion: Our nomogram is in agreement with one of the previously published nomograms that also measured umbilical cord diameter at the level of the fetal abdominal umbilical cord insertion. Therefore, we recommend umbilical cord thickness to be measured in close proximity to the fetal abdominal wall, but no further than 0.5 cm away from the wall insertion.

Our aim was to review the literature on umbilical cord coiling. Relevant articles in English published between 1966 and 2003 were retrieved by a Medline search and cross-referencing. The normal umbilical cord coiling index (UCI) is 0.17 (+/- 0.009) spirals completed per cm. Abnormal cord coiling, i.e. UCI <10th centile (<0.07) or >90th centile (>0.30) is associated with adverse pregnancy outcome. Hypocoiling of the cord is associated with increased incidence of fetal demise, intrapartum fetal heart rate decelerations, operative delivery for fetal distress, anatomic-karyotypic abnormalities and chorio-amnionitis. Hypercoiling of the cord is associated with increased incidence of fetal growth restriction, intrapartum fetal heart rate decelerations, vascular thrombosis and cord stenosis. It is not clear whether abnormal coiling is actually a cause of pathology, or merely one of the sequelae, or both. We discuss the theories involving the cause of cord coiling, and the consequences of the degree of cord coiling on blood flow through the umbilical vessels. In the future ultrasonographic evaluation of the umbilical cord and the UCI may become an integral part of fetal assessment in high-risk pregnancies.

Cystic periventricular leukomalacia (cPVL), the principal ischemic brain injury in premature infants, is characterized by necrosis of the white matter in the periventricular region and the major neuropathology for spastic motor deficits in cerebral palsy or epilepsy. Recent reports strongly suggest that the brain injury associated with cPVL may have already occurred in utero. In this study we searched retrospectively for possible clinical situations related to cPVL to facilitate assessment of optimal management. A total of 201 babies born at gestational ages from 24 to 33 weeks were entered into the study (1992-1997) and examined for involvement of 18 factors in cPVL retrospectively. And psychomotor development was examined at least until 18 months of corrected age. Among 201 premature babies 35 cases were diagnosed as cPVL later developed spastic diplegia. There are 23 cases of preeclampsia, no infant suffering from cPVL. In the univariate analysis, exposure to antenatal indomethacin, cord length > or =40 cm, and a low Apgar score were significantly associated with a 2-3 risk increased of cPVL occurrence, while antenatal magnesium sulfate reduced the risk. Chorioamnionitis was positively correlated with the risk, but did not reach statistical significance. In the multivariate analysis we found the statistical significance in exposure to antenatal indomethacin, a low Apgar score, and antenatal magnesium sulfate. Our results suggested that preeclampsia and antenatal exposure of magnesium sulfate reduced the risk while antenatal exposure of indomethacin and low Apgar score associated with the occurrence of cPVL. These findings support a growing consensus that cPVL is often the result of maternal and fetal factors as well as antenatal treatment.

Objective: To establish the reference ranges for first trimester umbilical cord and vessel diameters of Thai fetuses., Material and Method: A prospective study was performed on normal pregnant women between 10(+0) and 13(+6) weeks of gestation who underwent ultrasound examination. The diameter measurements were obtained by a 7.5 MHz vaginal--or a 3.75 MHz abdominal transducer. Statistics were analyzed using SPSS computer program., Results: Records of 184 pregnancies were analyzed and the outcome demonstrated a strong correlation between umbilical cord diameter and gestational age (r = 0.90; p < 0.001). Umbilical vessel diameters were also correlated with gestational age., Conclusion: First trimester umbilical cord and vessel diameters of Thai fetuses are related to gestational age. The presented reference ranges might be useful for further studies, such as prediction of adverse pregnancy outcome or combination with biochemical or other ultrasound markers for fetal aneuploidy screening.

We have investigated the importance of adhesion molecule co-operation in mediating Plasmodium falciparum adhesion to endothelial cells under flow conditions. Using three laboratory parasite lines and a patient isolate which differ in their ICAM-1 and CD36-binding avidity, we found that blockade of ICAM-1 and CD36 separately reduced IRBC adhesion by up to 95 and 50%, respectively. These results confirm previous data showing that ICAM-1 and CD36 synergize to mediate adhesion, but differ in demonstrating that without ICAM-1, binding under flow conditions is severely impaired. Thus, in this system, ICAM-1 is critical for P. falciparum adhesion to activated endothelium and once bound, synergy with CD36 mediates the majority (> or =98%) of adhesion.

Objectives: To investigate the relationship between parity and cord length, with respect to peripartum characteristics., Study Design: Parity, cord length, placental and birth weight were the studied variables in a sample of 534 parturients with singleton fetuses. Parturients were divided into four groups: primiparous (para-1), secundiparous (para-2), tetriparous (para-3) and multiparous (para >3). Oneway ANOVA and post-hoc tests were applied for the comparison of mean cord length between the four groups of parity. General Linear Model was applied for the detection of covariates., Results: ANOVA yielded significant differences between the four groups. Mean cord length was significantly higher in women of parity >or=3 than in women with lower parity. Although both placental and birth weight were correlated with cord length, application of GLM showed that only birth weight could act as a covariate for the length differences between parity groups., Conclusions: Cord length appears to increase with advancing parity, the cut-off point being between the second and the third labor. We suggest that intrapartum monitoring should be performed in all multiparous parturients, because of their propensity for longer cords, and thus for related complications.

True umbilical cord knot often remains undiscovered prenatally due to a lack of characteristic clinical or ultrasound signs. We present a pregnancy with favorable outcome in which a non-stress test (NST) found non-reassuring fetal status. Abnormal Doppler blood flow patterns in the descending aorta and in the middle cerebral artery revealed fetal arterial redistribution with normal circulation in the umbilical artery despite a true cord knot. The benefit of fetal Doppler assessment is discussed. Increased aortic-cerebral ratio may reflect acute hypoxic compromise caused by the transitory constriction of the true umbilical cord knot with unrecognized morphologic and circulatory signs.