Objective: Associations between magnitude and timing of maternal pregnancy blood lead (Pb) levels (BLLs), birth weight, and total days of gestation were examined, as well as associations with related clinical diagnoses of low birth weight (LBW), preterm, and small-for-gestational-age (SGA) birth.Study Design: Among a sample of 262 mother-infant pairs studied retrospectively, one-way analysis of variance and regression statistics were used to measure the relationship between level of maternal pregnancy BLLs and birth outcomes while controlling for key maternal and newborn factors. Results: Women with maximum pregnancy BLLs (max-PBLLs)X10 mg/dl tended to give birth earlier and their babies were at substantially increased risk for preterm and SGA birth. By holding other explanatory factors constant, each unit increase in max-PBLL above 10 mg/dl was found to be associated with a decrease of À0.3 in total days of gestation. Compared to women with lower levels, women with maxPBLLs X10 mg/dl were at a threefold increased risk for preterm birth (adjusted OR ¼ 3.2, 95% CI 1.2-7.4) and more than a fourfold increased risk for having an SGA infant (adjusted OR ¼ 4.2, 1.3-13.9). Second trimester maximum BLLs X10 mg/dl were associated with a steep decrease in total days of gestation (a decrease of À1.0 days per each unit increase above 10 mg/dl).Conclusions: These data provide evidence of the adverse effects of maternal pregnancy BLLs, particularly when levels are X10 mg/dl. Prenatal Pb exposure at these levels was associated with significant decreases in total days of gestation and an increased risk of preterm and SGA birth.
The purpose of this study was to investigate the efficacy and practicality of magnetic resonance angiography (MRA) in evaluating pediatric cerebrovascular disorders. A retrospective evaluation was performed of MR angiograms in 20 pediatric patients with cerebrovascular pathology. When appropriate, comparisons were made with duplex ultrasonography or conventional catheter angiography. MRA accurately assessed the patency of carotid reanastomoses in 8 babies who had previously undergone extracorporeal membrane oxygenation (ECMO). In 6 patients with moyamoya syndrome, MRA accurately evaluated stenotic intracranial carotid and circle of Willis arteries and progressive enlargement of the superficial temporal and middle cerebral arteries after revascularization procedures, and thus obviated the need for sequential angiograms. Thrombi and emboli were identified in 4 of 5 patients with symptoms and imaging evidence of an acute stroke. Two-dimensional time-of-flight MR venograms, acquired in both axial and coronal planes, were useful for preoperative venous mapping in a patient with an occipital encephalocele and detecting venoocclusive disease. MRA provided diagnostically useful information in a spectrum of pediatric cerebrovascular disorders. It can be used as the initial vascular imaging modality for patients with imaging evidence of acute cerebrovascular event, to evaluate progression of chronic vasoocclusive disease, to evaluate vessel patency following intracranial revascularization surgery, and for visualization of the venous circulation.
The effects of fetal nutritional supplementation on experimentally induced growth retardation were investigated in third-trimester sheep. The control group, C, was fed ad libitum (n = 8). Group R received a protein- and calorie-restricted diet over the last 3 weeks of gestation (n = 8). Group RS was given the same restricted diet as group R, and fetal, intragastric supplements of amino acids and glucose (n = 7). Over the experimental period, maternal weight increased 4.1 ± 0.6 kg in C but was stable in R and RS (p < 0.01). R and RS ewes and fetuses showed biochemical evidence of malnutrition but the changes were less severe in the RS group (p < 0.05). Nutrient levels did not change in group C ewes and fetuses. At delivery, R lambs were smaller in weight and length than RS or C (p < 0.05); gestational ages were the same. Weights were: R, 2,702 ± 182 g; RS, 3,235 ± 121 g; and C, 3,290 ± 297 g. R also had lower fetal to maternal weight ratios and higher brain to body weight ratios than RS or C (p ≤ 0.05). Placental size was reduced 28% in R compared to C (p < 0.05) and was intermediate in RS. The disparity in fetal size was explained by differences in nutrient acquisition between groups. Over the experimental period, caloric intake rose 24% in C fetuses; near delivery, they had the highest umbilical uptakes of carbohydrate and α-amino nitrogen. After maternal diet was limited, R and RS fetuses had dramatic decreases in umbilical uptake of α-amino nitrogen and static umbilical uptakes of carbohydrate. Caloric intake fell 42% in R. RS fetuses, however, were receiving sufficient gastric supplementation so that umbilical + gastrointestinal carbohydrate uptake equalled that of controls, and entry of α-amino nitrogen and calories was intermediate, between those of R and C. Fetal oxygen consumption reflected the differences in nutrient uptake, being greatest in C, lowest in R and intermediate in RS. Fetal supplementation lessened the drain on maternal nutrients and promoted more normal fetal growth and metabolism.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.