Large Fetus Research Articles

Hypertrophic cardiomyopathy‐like changes in monochorionic twin pregnancies with selective intrauterine growth restriction and intermittent absent/reversed end‐diastolic flow in the umbilical artery

To evaluate the prevalence of hypertrophic cardiomyopathy-like (HCL) changes in monochorionic twins with selective intrauterine growth restriction (sIUGR) and intermittent absent/reversed end-diastolic flow (iAREDF), also defined as Type III sIUGR, and the clinical relevance of this condition. A total of 80 pregnancies with sIUGR were studied, 40 with, and 40 without iAREDF. HCL changes were defined as an increased thickness of either left or right ventricular wall (mean > 2 SD) estimated with M-mode ultrasonography. Data were plotted on normal reference values constructed from 75 uncomplicated monochorionic twin pregnancies (150 fetuses) at 22-34 weeks' gestation. Perinatal outcomes in pregnancies with and without HCL changes were compared. In the group with iAREDF, 8/40 of the larger twins (20%) had HCL changes (five bilaterally, two in the right, and one in the left ventricle) as compared with 1/40 (2.5%) in fetuses without iAREDF (P = 0.03). No differences were observed in the smaller twin (1/40 in both groups). HCL changes were not associated with a significant increment in perinatal mortality as only one large fetus from the group with iAREDF died in utero. In the remaining 10 cases, no differences in the intertwin weight discordance, placental surface discordance, or rate of neonatal neurological damage were observed. However, all 10 presented mildly abnormal neonatal cardiac findings that resolved over time with no apparent short-term impact on cardiac function. HCL changes in the larger twin should be regarded as part of the spectrum of findings in Type III monochorionic-sIUGR (presenting iAREDF). This finding does not seem to be associated with an increased rate of short-term neurological or cardiac complications.

Three‐dimensional volumetry and fetal weight measurement

Three‐dimensional volumetry and fetal weight measurement

Fetal Transcerebellar Diameter Measurement for Prediction of Gestational Age at the Extremes of Fetal Growth

The purpose of this study was to determine the accuracy of our previously published and prospectively validated transcerebellar diameter (TCD) nomogram in the prediction of gestational age (GA) in intrauterine growth-restricted (IUGR) and large fetuses. We established a cross-sectional nomogram of TCD in 24,026 well-dated singleton fetuses and prospectively validated the nomogram using 2597 fetuses from a separate population. This nomogram was validated in both IUGR (n = 55) and large (n = 16) fetuses (estimated fetal weight, <10th and >90th percentiles, respectively). The actual GA was subtracted from the TCD-predicted GA in IUGR and large fetuses, and the concordance between the actual and predicted GAs was assessed using the Pearson correlation coefficient. Concordance between the actual and predicted GA based on our previously published singleton TCD nomogram was high for both IUGR and large fetuses (Pearson correlation, r = 0.98 and 0.95, respectively; P < .001). The means (SDs) of actual and predicted GA based on TCD in IUGR fetuses were 24.9 (6.5) and 25.1 (6.3) weeks, respectively. The predicted GA based on TCD in IUGR fetuses was within 3 days in 97.5% in the second trimester and 93.3% in the third trimester. In large fetuses, the difference between the actual and predicted GA based on TCD within 3 days was 100% in both the second and third trimesters. This study shows that our institution-specific TCD nomogram is reliable and accurate in predicting GA even at extremes of fetal growth.

Gabapentin for the treatment of neuropathic pain in a pregnant horse

A 24-year-old 732-kg (1,610-lb) pregnant Belgian draft horse mare developed neuropathy and signs of intractable pain following colic surgery. Following recovery from colic surgery to treat compression of the small and large intestines because of a large fetus, the mare was noticed to have signs of femoral neuropathy involving the left hind limb. Within 36 hours after recovery, the mare developed signs of severe pain that were unresponsive to conventional treatment. No gastrointestinal tract or muscular abnormalities were found, and the discomfort was attributed to neuropathic pain. The mare was treated with gabapentin (2.5 mg/kg [1.1 mg/lb], PO, q 12 h). Shortly after this treatment was initiated, the mare appeared comfortable and no longer had signs of pain. Treatment was continued for 6 days, during which the dosage was progressively decreased, and the mare was discharged. The mare subsequently delivered a healthy foal. Gabapentin appeared to be a safe, effective, and economical treatment for neuropathic pain in this horse.

The research implications of the selection of a gestational age estimation method

There are three primary methods of gestational age estimation: dating based on last menstrual period (LMP), ultrasound-based dating and neonatal estimates. We review the strengths and limitations of each method as well as their implications for research. Dating based on LMP is a simple, low-cost method of estimating gestational age. Limitations associated with the use of menstrual-based dating include reporting problems such as uncertainty regarding the LMP date, possibly due to bleeding not associated with menses, as well as concerns about the incidence of delayed ovulation, which can result in invalid estimates of gestation, even for women with certain LMP dates. Given that most women in the US have at least one ultrasound during pregnancy, it is becoming increasingly common for clinicians to verify menstrual dates using early ultrasound. To calculate gestational age with the use of ultrasound, fetal measurements are compared with a gestational age-specific reference. The primary limitation of this method is the fact that the gestational age estimates of symmetrically large or small fetuses will be biased. Further, given that ultrasound references were developed using pregnancies that were dated according to reliable LMP dates, they are potentially biased in the same direction as dates calculated according to LMP. Neonatal estimates of gestational age have been shown to be the least precise dating method. To highlight the research implications of the choice of a gestational dating method, we used data from the Routine Antenatal Diagnostic Imaging with Ultrasound Study to identify risk factors for post-term delivery. Risk factors for post-term delivery are shown to vary according to the choice of a gestational dating method, suggesting that some findings are an artefact of the choice of a method rather than evidence of causality.

Differences in placental structure during gestation associated with large and small pig fetuses1,2

The efficiency of nutrient transport from the pregnant female pig to the developing fetus depends on the size and function of the placenta. It has been reported that maternal and fetal blood vessels are arranged in a cross-countercurrent arrangement within placental microscopic folds. Thus, the blood supplies are in close apposition to each other within these microscopic folds, and maternal and fetal blood flows in approximately opposite directions perpendicular to the plane of the placenta. This arrangement indicates that the width of the microscopic folds influences placental efficiency. The objective of this study was to determine whether differences in pig placental microscopic fold development are associated with differences in fetal size or are influenced by selection for ovulation rate or uterine capacity. Gilts from a randomly selected control line, a line selected for ovulation rate, and a line selected for uterine capacity were slaughtered, and uterine wall samples were collected within the placentas associated with the largest and smallest fetuses in each litter on d 45, 65, 85, and 105 of gestation. The uterine wall samples were processed for histology and analyzed using computer-assisted morphometry. Average width of the placental folds and average width of the placental stroma above the folds were measured. To measure fold complexity, the length of the epithelial bilayer for a given length of placenta was also measured. The width of the folded bilayer increased significantly from d 65 to 105 and was greater in placentas associated with small fetuses compared with large fetuses on d 105 of gestation. In contrast, the width of the placental stroma above the folded bilayer decreased with gestation and decreased more rapidly in placenta associated with the smallest compared with the largest fetus. These results indicate that the width of the microscopic folds of the placental trophoblast/endometrial epithelial bilayer is increased in placenta associated with small fetuses, which we hypothesize will increase the surface area for interaction between maternal and fetal blood supplies, thus improving placental efficiency in response to reduced placental size.

Brief hyperglycaemia in the early pregnant rat increases fetal weight at term by stimulating placental growth and affecting placental nutrient transport

In pregnant women with type 1 diabetes, suboptimal glucose control in the first trimester is a strong predictor for giving birth to a large fetus. However, the mechanisms underlying this association are unknown. We hypothesized that transient hyperglycaemia in early pregnancy results in (1) increased placental growth and (2) an up-regulation of placental nutrient transport capacity, which leads to fetal overgrowth at term. In order to test this hypothesis, pregnant rats were given intraperitoneal injections of glucose (2 g kg(-1), resulting in a 50-100% increase in blood glucose level during 90 min) or saline (control) in either early or late gestation using four different protocols: one single injection on gestational day (GD) 10 (n=5), three injections on GD 10 (n=8-9), six injections on GD 10 and 11 (n=9-11) or three injections on GD 19 (n=7-8). Multiple injections were given approximately 4 h apart. Subsequently, animals were studied on GD 21. Three glucose injections in early pregnancy significantly increased placental weight by 10%, whereas fetal weight was found to be increased at term in response to both three (9% increase in fetal weight, P<0.05) and six glucose injections (7%, P=0.05) in early gestation. A single glucose injection on GD 10 or three injections of glucose on GD 19 had no effect on placental or fetal growth. In groups where a change in feto-placental growth was observed, we measured placental system A and glucose transport activity in the awake animals on GD 21 and placental expression of the glucose and amino acid transporters GLUT1, GLUT3, SNAT2 (system A), LAT1 and LAT 2 (system L). Placental system A transport at term was down-regulated by six glucose injections in early pregnancy (by -33%, P<0.05), whereas placental mRNA and protein levels were unchanged. No long-term alterations in maternal metabolic status were detected. In conclusion, we demonstrate that transient hyperglycaemia in early pregnancy is sufficient to increase fetal weight close to term. In contrast, brief hyperglycaemia in late pregnancy did not stimulate fetal growth. Increased fetal growth may be explained by a larger placenta, which would allow for more nutrients to be transferred to the fetus. These data suggest that maternal metabolic control in early pregnancy is an important determinant for feto-placental growth and placental function throughout the remainder of gestation. We speculate that maternal metabolism in early pregnancy represents a key environmental cue to which the placenta responds in order to match fetal growth rate with the available resources of the mother.

Ecological Correlates of Range Size in the Tent-Making BatArtibeus watsoni

We examined variation in foraging- and roosting-range size in the tent-making bat Artibeus watsoni .W e radiotracked 42 individuals at 2 sites in the Golfito Wildlife Refuge and 6 sites at Corcovado National Park, southwestern Costa Rica. Average home-range size of A. watsoni was the smallest recorded for a bat species (3.6 ha). Site, age, reproductive status, habitat, and season all had significant effects on foraging ranges, but sex and population abundance did not. Bats from the most productive sites, such as primary forests, had smaller foraging ranges, and subadults ranged farther than adults. During the dry season, females in late pregnancy had the smallest foraging ranges of all, most likely as a result of flight constraints imposed by the large fetus and an increase in fruit availability. Conversely, lactating females sampled during the early rainy season had among the largest foraging ranges. Males had significantly smaller roosting ranges than females, and adult bats sampled from areas of low roost abundance and high population abundance had smaller roosting ranges. However, subadults appeared to be unaffected by such changes in resource abundance, perhaps because they often roost in unmodified leaves. Although differences in resource availability and competition were important in determining roosting-range size, these effects were concealed by effects of reproductive activities such as mating, pregnancy, and lactation. Reproductive condition, along with foraging and roosting resource abundance, were largely responsible for determining ranging patterns in A. watsoni, but factors influenced foraging- and roosting-range size in different ways.

A prova de trabalho e a via de parto em primíparas com uma cesárea anterior

To identify factors associated with cesarean section in women with only one previous delivery by cesarean section and undergoing a trial of labor. A retrospective cross sectional study was performed from 1986 to 1998 including a total of 1746 women with one prior cesarean section and delivering after a trial of labor. Cases with a current twin pregnancy or with malformation incompatible with life were excluded. Women were divided in two groups according to the mode of the second delivery: Cesarean (n=731) or Vaginal Birth After Cesarean (VBAC, n=1015). To identify factors associated to the mode of delivery, the prevalence ratios (PR) and the 95%CI for each isolated factor, adjusted according to age, were assessed. In each analysis, cases with missing information were excluded. The total rate of Vaginal Birth After Cesarean was 58.1%. The factors significantly associated with cesarean section were: higher maternal age, greater fundal height (PR 1.5; 95%CI 1.19-1.88), premature rupture of membranes (1.3; 1.08-1.54), amniotic fluid with an altered aspect (1.22; 1.04-1.43) or volume (1.32; 1.01-1.73), altered fetal heart rate (1.96; 1.68-2.28), non cephalic presentation (2.03; 1.54-2.66), induction of labor (1.74; 1.42-2.11) and no labor analgesia (2.57; 2.11-3.11). The factors associated with cesarean section were older age, non-cephalic presentation, premature rupture of membranes, signs of large fetus, the need of induction of labor and signs of compromised fetal wellbeing.

Rechtsseitige Unterbauchschmerzen zwei Wochen postpartal

We report the CT imaging findings of a 33 year old patient who presented to the emergency department with increasing right lower abdominal pain and shivering. She delivered a healthy baby two weeks ago after induction in the 39th week of pregnancy due to a large fetus. Two days after delivery, sterilisation was performed. Clinically the primary differential diagnosis was appendicitis. However, computed tomography revealed thrombosis of the right ovarian vein. Consequently, management was altered appropriately with administration of antibiotics as well as a therapeutic dose of low molecular weight heparin.

P13.06: The effect of second‐trimester fetal morphometry on duration of pregnancy

Mean length of pregnancy is calculated to be 280–282 days from the first day of the last menstruation (LMP). Second-trimester ultrasound biometry seems to determine day of confinement more precisely than certain LMP. We hypothesized that the reason could be that small fetuses have a longer duration of pregnancy compensating for the underestimated age at time of scanning. The aim of this study was therefore to determine the relationship between second-trimester biometry and duration of pregnancy. This was a prospective cross-sectional study of 541 low-risk singleton pregnancies with regular certain LMP and spontaneous delivery. Head circumference (HC), abdominal circumference (AC) and femur length (FL) were measured at 10–24 weeks of gestation. Gestational age was calculated from LMP and birth weight noted. ANOVA and parametrical tests were used for the analysis. Results: Small fetuses (< 10 thpercenthile) had significantly (p < 0.005) longer duration of pregnancy than large fetuses (> 90 thpercenthile). Smallness of HC, AC and FL was associated with pregnancy duration of 288.4, 286.8, and 286.8 days, respectively. Large HC, AC and FL resulted in pregnancy duration of 280.8, 277, and 277 days, respectively. Interestingly, small HC and AC resulted also in significantly (p < 0.005) lower birth weight (3570 and 3418 gram, respectively) compared to those with large biometry (3943 and 3837 gram, respectively). Small fetuses measured at the second-trimester scan tend to have lower birth weight and longer pregnancies compared to large fetuses (at the most 9.8 days). An extended duration of pregnancy did not compensate reduced birth weight.

Delivery of the posterior arm reduces shoulder dimensions in shoulder dystocia

Objective: To evaluate a possible reduction in shoulder diameter and circumference by extending the posterior arm during delivery, for an easier birth in cases of shoulder dystocia. Methods: In this study of 33 neonates the bisacromial diameter and axilloacromial circumference were measured within 72 h of birth, first with the neonate's arms by its chest and then with 1 arm extended above its head. Reductions in diameter and circumference were evaluated. Results: The mean ± SD differences in bisacromial diameter and axilloacromial circumference were 1.9 ± 0.69 cm and 2.52 ± 1.18 cm, respectively. A greater reduction was observed in neonates with a greater shoulder diameter. Conclusion: In cases of shoulder dystocia, delivery of the posterior arm should significantly reduce shoulder dimensions, especially in larger fetuses, and prevent a need for excessive traction.

Transfer of Inner Cell Mass Cells Derived from Bovine Nuclear Transfer Embryos into the Trophoblast of BovineIn Vitro–Produced Embryos

Presence of placental tissues from more normal noncloned embryos could reduce the pregnancy failure of somatic cloning in cattle. In this study, inner cell mass (ICM) cells of in vitro-produced (IVP) embryos was replaced with those of nuclear transfer (NT) embryos to reconstruct bovine blastocysts with ICM and trophoblast cells from NT and IVP embryos, respectively. A total of 65 of these reconstructed embryos were nonsurgically transferred to 20 recipient beef females. Of those, two females were diagnosed pregnant by ultrasonography on day 30 of gestation. One pregnancy was lost at 60-90 days of gestation, and the other recipient cow remained pregnant at day 240 of gestation; however, this female died on day 252 of gestation. Gross pathology of the internal organs of the recipient female, a large fetus, and a large placental tissue mass suggested the massive size of the fetus and placental tissue were likely involved in terminating the life of the recipient female. Biopsy samples were harvested from the skin of the dead recipient cow, the fetus and from cotyledonary tissue. Microsatellite DNA analysis of these samples revealed that the genotype of the fetus was the same as that of the NT donor cells and different from that of the recipient cow. Correspondingly, neither the fetus nor recipient cow had the same genotype with that of the fetal cotyledonary tissue. These results present the first known documented case of a bovine somatic NT pregnancy with nonclone placental tissues after transfer of a blastocyst reconstructed by a microsurgical method to exchange of ICM cells and trophoblast tissue between NT and IVP blastocysts.

Clinical vs. ultrasound evaluation of fetal weight

Evaluating fetal weight is an important part of obstetrics. Accurate estimations can help in deciding the timing and mode of delivery of growth restricted and large fetuses. Methods of evaluating fetal weight include clinical and ultrasonographic. Since ultrasonographic facilities are expensive, not easily available and trained personnel are required, it would be immensely useful to know if other simpler clinical methods can estimate fetal weight with the same degree of accuracy. The study was conducted in the Department of Obstetrics and Gynecology, All India Institute of Medical Sciences, New Delhi, from January 2002 to January 2003. Forty-six pregnant women with singleton fetuses who had completed 35 weeks of gestation were recruited. Informed consent was taken. The fetal weight was estimated by abdominal palpation method using Leopolds maneuvers. This was performed by a single obstetrician (KB) who had 8 years of experience in Obstetrics and Gyne-

The Current State of Knowledge About the Effects, Risks, and Science of Children’s Environmental Exposures

In the preface1 to this supplement, we pointed out that pediatricians and other clinicians have made major contributions to the discovery of environmental toxicants. Many acute illnesses that are caused by high exposures to some toxicants are clinically diagnosable or at least are commonly in the differential diagnosis, eg, organophosphate poisoning, infant botulism, acute lead encephalopathy, carbon monoxide poisoning, acrodynia, hypervitaminosis A and some cases of aplastic anemia, convulsions, asthma, respiratory distress, methemoglobinemia, Reyes syndrome, kernicterus, and many of the recognizable syndromes that result from exposures to teratogenic drugs and chemicals. In contrast to the obvious effects of high exposures to environmental toxicants, there is less information and less certainty concerning the magnitude of the contribution of many low exposures of environmental toxicants to morbidity, mortality, and subtle alterations in children as well as adults or how the effects of these exposures vary with age or chronicity of exposure. We also informed the readership that we were going to address the issue of environmental toxicology from both a clinical and a toxicologic viewpoint. Very low exposures to environmental toxicants may lead to diseases that resemble many common illnesses that have other causes, or they may lead to decrements in functioning that are subtle or nonspecific. It is an almost insurmountable task for individual practitioners to conclude a cause-and-effect relationship from low exposures to environmental toxicants among patients in the physician’s patient population. Only well-planned, sophisticated epidemiologic and animal studies can answer the questions that pertain to the toxicity of low-level exposures to environmental toxicants, given that not all individuals will be affected equally, if at all, at any particular level of exposure. Many of the previous multi-authored compendia that have been published by groups of scientists have been unified in their conclusions that environmental toxicants are a very serious … Reprint requests to (R.L.B.) Rm 308, R/A, Alfred I. duPont Hospital for Children, Box 269, Wilmington, DE 19899. E-mail rbrent{at}nemours.org

Prevention and Control of Anemia: Thailand Experiences

Thailand has addressed nutrition in national development policy since the mid-1970s, including efforts to reduce iron deficiency anemia. Nutritional improvement has been implemented as an integral part of primary health care and community development extending beyond government services to include community participation. Utilization of village health volunteers has been a crucial feature of the program. Available data indicate that anemia rates have declined among pregnant women and preschool children, although there has been no formal evaluation of the program effect. Universal iron supplementation has been the major strategy for pregnant women, using village health volunteers to encourage continuation of the antenatal care schedule and encouraging a preventive approach by health service providers. Program obstacles have included lack of access to iron tablets by some populations and lack of understanding of the importance of anemia. Women's compliance was complicated by fear of having a large fetus, forgetfulness and side effects. Weekly iron supplementation of school children was piloted in 2000, and is now being extended. Other strategies utilized to address iron deficiency include food fortification, dietary improvement and complementary public health measures. Program monitoring and evaluation require strengthening to assess the effectiveness of intervention strategies and provide proper data for decision-making.

Lustrupholm – Et brandgravfelt fra ældre bronzealder under flad mark

Lustrupholm – Et brandgravfelt fra ældre bronzealder under flad mark

Doppler velocimetry for predicting fetal death in a twin pregnancy

Doppler velocimetry for predicting fetal death in a twin pregnancy

Maternal nutritional manipulation of placental growth and glucose transporter 1 (GLUT-1) abundance in sheep

Glucose transporter 1 (GLUT-1) is the predominant glucose transporter in the placenta but the extent to which its abundance is nutritionally regulated is unknown. This study investigated the effects of restricted maternal nutrition between day 28 and day 80 of gestation followed by re-feeding to either meet or to exceed the total energy requirements on placental size and GLUT-1 abundance at mid-gestation (that is, day 80) and near to term (that is, days 140-145 of gestation; term = 147 days). Singleton bearing ewes either consumed 8.7-9.9 MJ day(-1) of metabolizable energy (that is, well fed) or 3.2-3.8 MJ day(-1) of metabolizable energy (that is, nutrient restricted) from day 28 to day 80 of gestation, after which stage they consumed either 6.5-7.5 MJ day(-1) (that is, adequately fed) or 8.0-10.9 MJ day(-1) (that is, well fed) of metabolizable energy until near to term. In all ewes, at both sampling dates, the abundance of GLUT-1 was higher in the maternal component than in the fetal component of the placenta. Immunohistochemistry confirmed that GLUT-1 was located in the maternal uterine syncytium. At day 80 of gestation, placental mass was lower (P < 0.05) in the nutrient restricted group, but there was no difference in the abundance of GLUT-1 between the nutrient restricted group and the well fed group. At near term, placental mass was greater (P < 0.05) in ewes that were nutrient restricted during early to mid-gestation and then adequately fed up to term compared with ewes that were well fed during early to mid-gestation. This increase was associated with a higher (P < 0.05) abundance of total placental GLUT-1 and a larger fetus. There was no effect of previous nutrient restriction on placental mass, fetal weight or GLUT-1 abundance at term, when ewes were well fed in the second half of gestation. In conclusion, maternal nutrient restriction between early to mid-gestation alters placental growth but has no effect on placental GLUT-1 abundance. Increasing maternal feed intake to meet calculated energy requirements in previously nutrient restricted ewes during the second half of gestation, increases placental mass and fetal weight, and the abundance of GLUT-1, an adaptation not observed if maternal food intake is increased above requirements.

Non-reassuring fetal status in the prolonged pregnancy: the impact of fetal weight.

To evaluate the incidence of abnormal fetal findings and Cesarean delivery for non-reassuring fetal status as a function of birth weight in the uncomplicated prolonged pregnancy. Seven hundred and ninety-two patients at or beyond 41 weeks' gestation were managed expectantly. Population-specific birth-weight percentiles were calculated. Fetuses were retrospectively categorized as small (birth weight < 10th percentile), average (10th percentile < or = birth weight < or = 90th percentile) or large (birth weight > 90th percentile). The incidences of abnormal antepartum fetal testing results (i.e. oligohydramnios and/or abnormal non-stress testing) and Cesarean delivery for intrapartum non-reassuring fetal status were calculated for these three birth-weight categories. There was a significant inverse relationship between the incidence of abnormal fetal testing and birth-weight category (36%, 14% and 9% for small, average and large fetuses, respectively, P < 0.001). Small fetuses were more likely to require a Cesarean delivery for non-reassuring fetal status during labor than were all other fetuses (12.3% vs. 5.3%, P = 0.024). The frequency of oligohydramnios and abnormal non-stress testing is inversely related to birth weight in the expectantly managed prolonged pregnancy. In addition, small fetuses born at or beyond 41 weeks' gestation have an increased rate of Cesarean delivery for intrapartum non-reassuring fetal status.