孕期低水平铅暴露对胎儿的影响

随着现代工业和交通的发展,环境铅污染日趋严重,普通人群的低水平铅暴露对妊娠过程及远期的危害正日益受到重视。特别是胎儿期低水平铅暴露对胎儿及婴儿出生后生长发育,尤其是神经系统发育存在不良影响。我们以本区非职业性铅作业孕妇为研究对象,测定其孕中期、分娩前血铅(BPb)水平和新生儿脐血血铅水平,对3者血铅进行相关分析,现报告如下。     

新生儿脐血铅水平对新生儿神经行为发育的影响

环境铅污染不仅影响儿童的生长发育,对于胎儿同样造成损害,其中最早出现的是神经行为功能的改变.研究证明,孕期低水平铅暴露即可引起新生儿神经行为发育的异常,特别是对视听功能产生不良影响[1].本文通过对产妇血铅及新生儿脐血铅与新生儿神经行为发育评分的分析,了解其间的关系,探讨胎儿期铅暴露对新生儿神经行为发育的影响.     

新生儿脐血铅水平对新生儿神经行为发育的影响

环境铅污染不仅影响儿童的生长发育，对于胎儿同样造成损害，其中最早出现的是神经行为功能的改变。研究证明，孕期低水平铅暴露即可引起新生儿神经行为发育的异常，特别是对视听功能产生不良影响。本文通过对产妇血铅及新生儿脐血铅与新生儿神经行为发育评分的分析，了解其间的关系，探讨胎儿期铅暴露对新生儿神经行为发育的影响。     

低水平铅暴露对早期婴儿发育的影响

为了研究出生前后低水平铅暴露对儿童发育的影响，前瞻性观察了１０２例出生时血铅在０．１０～０．８４μｍｏｌ／Ｌ低水平铅暴露婴儿的发育，通过多因素统计评价其因果关系。结果发现，即使在这个以往完全被认为是正常的铅暴露范围内，脐血血铅水平与３个月时在Ｂａｙｌｅｙ发育量表上的精神发育指数（ＭＤＩ）和心理运动发育指数（ＰＤＩ）有明确的负相关关系。血铅≥０．４８μｍｏｌ／Ｌ的婴儿在３月龄时的ＭＤＩ和ＰＤＩ明显低于血铅水平＜０．４８μｍｏｌ／Ｌ者，分别相差４．６和８．８分，差异有非常显著意义（Ｐ＜０．０１）。经多元逐步回归分析和多元协方差分析，结果提示这种差异依然存在。提示儿童血铅水平≥０．４８μｍｏｌ／Ｌ时确能对其早期发育产生不利影响。其前瞻性的变化规律正在进一步观察之中     

胎儿期低水平铅暴露对婴儿发育影响的前瞻性研究

为了探讨胎儿期低水平铅暴露对婴儿出生以后发育的影响，于１９９３年８月－１１月间，在上海市杨浦区随测定了３４８位产妇分娩时婴儿脐带血铅水平。将脐带血铅水平在第７０百分位以上及第３０百分位以下的婴儿分别作为高铅组及低铅组，进行３、６、１２月龄发育随访。。     

吸烟对脐血铅水平及新生儿神经行为发育的影响

探讨吸烟与宫内铅暴露及新生儿神经行为的关系。方法选择我院1992～1997年8～10月间足月新生儿396例，以脐血铅含量作为新生儿宫内铅暴露的指标，新生儿神经行为评分作为效应指标，评价孕妇吸烟与新生儿神经行为的关系。结果孕期被动吸烟和主动吸烟可使脐血铅水平明显升高，脐血铅含量平均值达0．52和0．61μmol／L，高于安全界限（0．48μmol／L）的新生儿分别占69％和79％。当济血钳含量高于0．48μmol／L时，对神经行为发育有显著影响，特别对行为能力中的非生物听定向反应、生物性视和听定向反应影响更明显。结论孕期被动和主动吸烟可提高济血铅水平，并进一步影响新生儿神经行为发育，特别是视和听功能。     

新生儿脐血铅水平与骨代谢指标变化的相关性研究

目的探讨新生儿脐血铅水平与骨代谢指标间的相关性。方法采集80例正常新生儿脐静脉血5ml,分别检测血铅、血清骨钙素（OC）、骨碱性磷酸酶（ALP）及25-（OH）D3。结果脐血铅水平与胎儿OC、25-（OH）D3呈显著负相关,与ALP呈显著正相关。以P50（50.45μg/L）为界,较高脐血铅组血清OC[（10.0±5.84）ng/ml]、25-（OH）D3[（47.52±28.82）μg/L]均显著低于较低脐血铅组血清OC[（19.26±4.32）ng/ml,P〈0.001]、25-（OH）D3[（56.62±26.80）μg/L,P〈0.05];高血铅组骨ALP水平[（182.64±44.67）U/L]显著高于低血铅组[（126.43±62.05）U/L,P〈0.05）]。结论胎儿期低水平铅暴露可能影响骨形成过程,阻碍正常骨矿化过程。     

白细胞介素-8和细胞间黏附分子-1在早产儿脑白质损伤早期变化及其与预后的关系

目的探讨脑白质损伤(CWMD)早产儿早期血清白细胞介素-8(IL-8)和细胞间黏附分子(ICAM-1)变化及其与预后的关系。方法对2009年3月至2012年6月收治并获得随访的102例CWMD早产儿(CWMD组)和42例正常早产儿(对照组),分别在生后48~72 h采集血清并检测IL-8和ICAM-1含量,12个月时采用Bayley婴幼儿发育量表对婴儿运动发育指数(PDI)及智能发育指数(MDI)进行评估,分析IL-8和ICAM-1水平与预后的相关性。结果轻、中、重CWMD组及对照组间血清IL-8和ICAM-1水平的差异有统计学意义(P0.05),且随着CWMD程度加重,IL-8和ICAM-1水平逐渐递增,差异有统计学意义(P均0.05)。轻、中、重CWMD组的PDI、MDI的差异有统计学意义(P0.05),且随着CWMD程度加重,逐渐递减,差异也有统计学意义(P均0.05)。CWMD组的血清IL-8和ICAM-1水平与MDI之间呈显著负相关(r=-0.64、-0.66,P均0.05),与PDI之间也呈显著负相关(r=-0.70、-0.71,P均0.05)。结论 CWMD早产儿出生后血清IL-8和ICAM-1水平显著增高,并且与其12月龄时的MDI及PDI呈显著负相关。     

低水平铅暴露与儿童神经行为发育

本文主要从孕期铅暴露对婴儿神经行为发育的影响和儿童铅暴露有无安全界限两大研究热点对低水平铅暴露与儿童神经行为发育的关系进行综述,一方面强调了孕期铅暴露防治的重要性,另一方面指出由于无证据证明在血铅水平与认知功能之间存在安全界限,因此有必要重新审视CDC和WHO所警示的铅中毒界限,同时对儿童铅中毒的防治提出前瞻性设想。     

体外受精受孕婴儿12月龄时精神运动发育状况

目的探讨辅助生殖技术受孕与自然受孕婴儿在12月龄精神运动发育水平有无差异。方法采用配对对照研究方法,将辅助生殖技术受孕婴儿(实验组)与自然受孕婴儿(对照组)在母亲年龄、产次、社会阶层、父母受教育程度等几方面严格配对后,自母亲孕28周起入组登记,定期随访,收集相关资料,至婴儿12月龄采用中国儿童发展中心(CDCC)婴幼儿发育量表行精神运动发育评估。结果实验组早产、低出生体质量、双胎妊娠率明显高于对照组,但二组12月龄智力发育指数(MDI)及运动发育指数(PDI)无显著差异。结论辅助受孕婴儿12月龄精神运动发育水平正常。但这一特殊人群因为高发的多胎妊娠、早产、低出生体质量等因素,其健康及以后的生长发育仍需长期随访跟踪。     

Smoking during pregnancy--effects on the fetus and on thiocyanate levels in mother and baby.

Twenty-eight mothers smoking 10--20 cigarettes daily during pregnancy had significantly higher serum thiocyanate concentrations at delivery compared in 25 non-smoking controls. The thiocyanate levels were positively correlated to cigarette consumption and inversely correlated to the birth weights of the infants. A highly significant correlation existed between serum thiocyanate levels of the mother and umbilical cord serum thiocyanate levels, reflecting a nearly complete equilibration. The thiocyanate concentrations in human milk on the 4th day after delivery were considerably lower than the serum concentrations, and no correlation existed between serum and milk concentrations. The infants of smoking mothers had significantly decreased weight and length at birth compared in infants of non-smokers. Birth weights were 3 344 +/- 434 g and 3 620 +/- 504 g respectively (p less than 0.05), and lengths 49.8 +/- 1.7 cm and 51 +/- 1.6 cm respectively (p less than 0.05). No differences were found between smokers and non-smokers in placental and umbilical cord histology, and umbilical cord artery medial area. It is concluded that serum thiocyanate concentration in smokers may be used as an objective measure for smoke exposure, and that maternal cigarette smoking acts as an exogenous factor which interferes with intrauterine development of the fetus in a dose related way.     

Thimerosal exposure (from tetanus‐diphtheria vaccine) during pregnancy and neurodevelopment of breastfed infants at 6 months

Aim: We studied the effect on neurodevelopment of infants who are exposed to thimerosal in tetanus‐diphtheria (Td) vaccines during pregnancy. Methods: We compared Gesell Developmental Schedules (GDS) of exclusive breastfed infants at 6 months born to mothers who received Td (1 to 3 doses) against those who were born to mothers who did not take such vaccines. Results: Compared with the group of infants not exposed to ethylmercury in utero, the infants of exposed mothers showed no significant difference in neurodevelopment delays. Although there was a significant correlation between hair‐Hg of mothers and hair‐Hg of neonates (Spearman r = 0.353; p = 0.0011), there was no significant correlation between the level of in utero exposure to ethylmercury in Td vaccines and neonate’s hair‐Hg concentrations (Spearman r = 0.060; p = 0.5922). However, regression analysis showed that GDS at 6 months was significantly associated with total mercury concentration of neonate’s hair but was not sensitive to the number of vaccines taken by the mother. Conclusion: Early neurodevelopment of exclusively breastfed infants is sensitive to in utero exposure to mercury, but maternal thimerosal exposure in tetanus‐diphtheria vaccines per se cannot portend clinical neurodevelopment delays measured by GDS at 6 months.     

未足月胎膜早破对早产儿神经发育的影响

目的探讨未足月胎膜早破对早产儿神经发育的影响。方法将早产儿根据产前有无胎膜早破分为未足月胎膜早破组（n=40）和对照组（n=37）。分别对二组患儿在纠正胎龄至40周、纠正胎龄后3个月、纠正胎龄后6个月进行新生儿神经发育评分（NBNA）及婴幼儿智能运动发育检测（CDCC）,比较二组神经发育情况。结果未足月胎膜早破组3个月及6个月运动心理发育指数（PDI）明显低于对照组,经统计学分析有显著性差异（Pa〈0.05）。二组NBNA评分、3个月及6个月智能发育指数（MDI）比较则无明显统计学差异（Pa〉0.05）。结论未足月胎膜早破对早产儿远期运动心理发育有明显的延迟和滞后的影响。     

No association between maternal psychological symptoms and infant outcome after pregnancy complicated by early-onset hypertensive disorders

Aim: The aim of this work was to study the effect of maternal psychological symptoms on infant development 1 year after early-onset hypertensive disorders of pregnancy.
Methods: All mothers were enrolled in the Pre-eclampsia, Eclampsia TRial Amsterdam. Mothers were asked to complete the 90-item Symptom Check List (SCL-90) at the corrected ages of their infants of 0, 3 and 12 months. The total sum score of these three checklists was calculated. Infants were examined at the corrected age of 12 months using the Bayley Scales of Infant Development (Mental Developmental Index [MDI] and Psychomotor Developmental Index [PDI] subscales). The Bayley scores were compared between infants of mothers with SCL-90 sum scores in the highest 25% and lowest 75%.
Results: For 141 mother–infant pairs (80%) all three SCL-90 checklists and Bayley scores were available. Mean gestational age was 32 weeks and 90% of the infants were growth restricted. The mean MDI was 87 in the highest 25% and 89 in the lowest 75% group. This was 79 versus 80 for the PDI.
Conclusion: In this population of high-risk growth-restricted infants born after a pregnancy complicated by early-onset hypertensive disorders, there is no additional impact of negative maternal psychological symptoms on infant development after 1 year.     

SMOKING DURING PREGNANCY—EFFECTS ON THE FETUS AND ON THIOCYANATE LEVELS IN MOTHER AND BABY

Abstract. Twenty-eight mothers smoking 10–20 cigarettes daily during pregnancy had significantly higher serum thiocyanate concentrations at delivery compared to 25 non-smoking controls. The thiocyanate levels were positively correlated to cigarette consumption and inversely correlated to the birth weights of the infants. A highly significant correlation existed between serum thiocyanate levels of the mother and umbilical cord serum thiocyanate levels, reflecting a nearly complete equilibration. The thiocyanate concentrations in human milk on the 4th day after delivery were considerably lower than the serum concentrations, and no correlation existed between serum and milk concentrations. The infants of smoking mothers had significantly decreased weight and length at birth compared to infants of non-smokers. Birth weights were 3344±434 g and 3620±504 g respectively ( p <0.05), and lengths 49.8±1.7 cm and 51±1.6 cm respectively ( p <0.05). No differences were found between smokers and non-smokers in placental and umbilical cord histology, and umbilical cord artery medial area. It is concluded that serum thiocyanate concentration in smokers may be used as an objective measure for smoke exposure, and that maternal cigarette smoking acts as an exogenous factor which interferes with intrauterine development of the fetus in a dose related way.     

Prediction for developmental delay on Neonatal Oral Motor Assessment Scale in preterm infants without brain lesion

Background:  Preterm infants often have difficulty in achieving a coordinated sucking pattern. To analyze the correlation between preterm infants with disorganized sucking and future development, weekly studies were performed of 27 preterm infants from initiation of bottle feeding until a normal sucking pattern was recognized.
Methods:  A total of 27 preterm infants without brain lesion participated in the present study. Neonatal Oral Motor Assessment Scale (NOMAS) was utilized to evaluate the sucking pattern. Infants who were initially assessed as having disorganized sucking on NOMAS and regained a normal sucking pattern by 37 weeks old were assigned to group I; infants with a persistent disorganized sucking pattern after 37 weeks were assigned to group II. The mental (MDI) and psychomotor (PDI) developmental indices of Bayley Scales of Infant Development, second edition were used for follow-up tests to demonstrate neurodevelopment at 6 months and 12 months of corrected age.
Results:  At 6 months follow up, subjects in group I had a significantly higher PDI score than group II infants ( P = 0.04). At 12 months follow up, group I subjects had a significantly higher score on MDI ( P = 0.03) and PDI ( P = 0.04). There was also a higher rate for development delay in group II at 6 months ( P = 0.05).
Conclusion:  NOMAS-based assessment for neonatal feeding performance could be a helpful tool to predict neurodevelopmental outcome at 6 and 12 months. Close follow up and early intervention may be necessary for infants who present with a disorganized sucking pattern after 37 weeks post-conceptional age.     

Fetal and infant lead exposure: effects on growth in stature

The growth of a cohort of 260 infants was prospectively followed up from birth. Blood lead and stature measurements were obtained every 3 months until 15 months of age. Fetal lead exposure was indexed by measuring lead in maternal blood during pregnancy. A longitudinal analysis revealed that covariate adjusted growth rates in stature were negatively related to the infants' postnatal blood lead concentration, as indexed by increase in average blood lead values from 3 to 15 months. However, this relationship between growth rate and change in blood lead concentration was evidenced only among those infants whose mothers had prenatal blood lead levels greater than the maternal cohort median of 7.7 micrograms/dL is about 2 cm shorter at 15 months of age if, postnatally, the infant incurred a 10-micrograms/dL blood lead increase during the 3- to 15-month interval of life, compared with an infant who has no increase.     

Blood glucose levels in a population of healthy, breast fed, term infants of appropriate size for gestational age

AIM: To determine blood glucose levels in a population of healthy, breast fed, term infants of appropriate size for gestational age. METHODS: In a cross sectional study, the blood glucose concentration of 223 healthy, breast fed, term infants of appropriate size for gestational age was determined at different times (between one and 96 hours) after delivery. One sample of blood glucose was taken from each infant independent of the feeding time. The glucose concentration was correlated with sex, method of delivery, delivery with or without analgesia, smoking status of the mother, gestational age, umbilical cord pH, and Apgar score. Infants suspected of suffering from intrapartum hypoxia were excluded. RESULTS: Blood glucose concentration one hour after delivery was not significantly lower than at any other time. Only two infants had low blood glucose concentrations one hour after delivery (1.4 and 1.9 mmol/l). There were no significant differences in blood glucose concentration between sexes, methods of delivery, infants delivered with or without analgesia, and infants born to smokers or non-smokers, and there was no further correlation between blood glucose concentration and gestational age, umbilical cord pH, or Apgar score. DISCUSSION: Very few healthy, breast fed, term infants of appropriate size for gestational age have low blood glucose levels, and there is no indication for blood glucose monitoring in these infants.     

25-hydroxyvitamin D and calcium levels in maternal, cord and infant serum in relation to maternal vitamin D intake

The plasma levels of 25-hydroxyvitamin D (25-OHD), total calcium, phosphorus and proteins were measured in 40 healthy mothers and their infants at the time of delivery during the months of December and January. Calcium, phosphorus and proteins were again measured in the plasma of the infants on the fourth day of life. Vitamin D intake of the mothers during their last 3 months of pregnancy were estimated by interviews. The mean (+/-SE) plasma levels of 25-OHD was 9.0 +/- 0.9 ng/ml in the mothers and 5.05 +/- 0.4 ng/ml in cords. There was a significant correlation between mother and cord plasma levels (r = 0.75, p less than or equal to 0.001). The concentration gradient of 25-OHD plasma levels between mother and cord is higher at high 25-OHD maternal concentrations. This suggests that the placenta plays a regulating role in the 25-OHD transfer between mother and foetus. The 4-day-old infants from mothers having a suboptimal vitamin D intake (less than 150 IU/day) have a lower mean serum plasma level than infants born from mothers with a vitamin D intake of more than 500 IU/day.     

Effects of Fetal Exposure to Diazoxide in Man

Four infants were born to women treated with oral diazoxide for the last 19 to 69 days of pregnancy. Maternal plasma levels of diazoxide in the 5 days before delivery were related to the intake of the drug and varied between 11 and 43 μg/ml. At delivery the umbilical plasma diazoxide level was lower than that in the mother and was 6·5 to 25 μg/ml. At the age of 24 hours the plasma diazoxide level in the infants had not altered appreciably. Diazoxide was present in the amniotic fluid and was excreted in the urine in the first week of life. Urinary diazoxide excretion was greatest on days 2 and 3 and had fallen to low or undetectable levels by days 6 and 7.