LEAD MOBILIZATION DURING PREGNANCY AND LACTATION IN URBAN WOMEN

病例报告表明，储存在骨骼中的铅在 怀孕和哺乳，将母亲，特别是 发育中的胎儿有铅中毒的风险。胎盘已经满了 对铅具有渗透性。为了研究骨骼铅是 在怀孕和哺乳期间动员，我们提出了一个前瞻性队列 老年人血铅、血浆铅、骨铅重复测定的研究 来自不同种族的年轻内城女性。我们假设 当铅在怀孕和哺乳期间被动员时，母亲和 胎儿血铅水平将增加，母血铅水平将增加 减少。 我们将比较骨铅、血浆铅和全血铅水平 怀孕时从同一名妇女那里获得的测量数据 产后期和产后六个月。我们假设 随着年龄的增长，骨铅水平将下降，血铅水平将上升。 妊娠期铅动员的结果。在乳房的女性中 产后六个月的测量将评估任何额外的 哺乳对铅动员的影响。类似的比较也将出现 在非怀孕妇女的对照组中进行。对照组将 使我们能够比较骨骼铅变化的自然历史 没有怀孕和哺乳。脐血铅水平 将决定评估母体体内循环铅的转移 刚出生的。 这一研究人群预计将有较高的身体铅负担作为 环境铅暴露的结果。这里的种族多样性 人口将使我们能够确定身体铅负荷是否 非裔美国人和西班牙裔女性的比例高于高加索女性。 我们还将评估身体负担较高的女性是否在 基线比体内铅含量低的女性动员更多的铅 负担。 有证据表明，充足的铁储备可以防止铅的吸收。 因此，可能会防止铅动员在 怀孕了。这项研究将调查铁储备对身体的影响 铅的负担有两个方面。首先，我们将确定较高的铁是否 根据血清铁蛋白水平评估的商店预测较低的身体负担 铅的含量。其次，我们将确定铁的储存水平是否 比较血清铁蛋白对妊娠期铅迁移的影响 治疗前后骨铅、血铅和血浆铅水平的测定 怀孕了。 这项研究将提供第一次定量检查 假设骨骼铅移动发生在怀孕期间和 哺乳。这项调查应该会为 慢性环境铅暴露对健康的潜在影响 孕妇、发育中的胎儿和婴儿通过母乳喂养。

Case reports suggest that lead stored in the skeleton is mobilized during pregnancy and lactation, placing the mother and, in particular, the developing fetus at risk of lead poisoning. The placenta is fully permeable to lead. To investigate the hypothesis that skeletal lead is mobilized during pregnancy and lactation, we propose a prospective cohort study with repeated measures of blood, plasma and bone lead in an ethnically diverse population of young, inner city women. We hypothesize that as lead is mobilized during pregnancy and lactation, maternal and fetal blood lead levels will increase and maternal bone lead levels will decrease. We will compare bone, plasma and whole blood lead levels prior to pregnancy with measurements obtained from the same women in the immediate postpartum period and six months after delivery. We hypothesize that bone lead levels will decrease and blood lead levels will increase as a result of lead mobilization during pregnancy. Among women who breast feed, the six month postpartum measurements will assess any additional effect of lactation on lead mobilization. Similar comparisons will also be made in a control group of non-pregnant women. The control group will allow us to compare the natural history of bone lead changes in the absence of pregnancy and lactation. Umbilical cord blood lead levels will be determined to assess maternal transfer of circulating lead to the neonate. This study population is expected to have a high body lead burden as a result of environmental lead exposure. The ethnic diversity of this population will enable us to determine whether body lead burdens are higher in African-American and Hispanic women than in Caucasian women. We will also assess whether women with higher body lead burden at baseline mobilize more lead than women with lower baseline body lead burden. Adequate iron stores have been shown to protect against lead absorption and therefore, possibly protect against lead mobilization during pregnancy. This study will investigate the effect of iron stores on body burden of lead in two ways. First, we will determine whether higher iron stores, assessed by serum ferritin levels, predict a lower body burden of lead. Secondly, we will determine whether the level of iron stores affects lead mobilization during pregnancy by comparing serum ferritin levels with bone, blood and plasma lead measurements before and after pregnancy. This study will provide the first quantitative examination of the hypothesis that skeletal lead mobilization occurs during pregnancy and lactation. The investigation should provide important insights into the potential health effects of chronic environmental lead exposure to pregnant women, developing fetuses and infants through breast feeding.