母亲孕早期血红蛋白水平与学龄前儿童智力发育的关系

目的 探讨母亲孕早期血红蛋白(Hb)水平对学龄前儿童智力发育的影响.方法 研究对象为浙江、江苏省13市(县)在1993-1996年期间分娩的妇女,2000-2001年对这些妇女所生育的儿童(平均68月龄)随机抽样,共得到3609个母子对.使用中国-韦氏幼儿智力量表对儿童进行智力测试;母亲孕早期的Hb浓度在首次产前检查时获得.分析母亲孕早期Hb浓度与所生儿童全量表智商、语言智商和操作智商得分之间的关系.结果 孕早期贫血组妇女所生儿童的语言智商、操作智商以及全量表智商得分,比非贫血组妇女所生儿童的智商得分分别高0.6、0.9和0.8分.调整儿童性别、智力测量时月龄、地区、产次以及母亲智商、文化程度、职业等因素后,未发现母亲孕早期贫血与儿童低语言智商、操作智商和全量表智商的风险之间存在统计学联系.按照每20个百分位间隔将妊娠期妇女孕早期Hb分成5组分析,Hb浓度偏低组(Hb＜103 g/L)、中等组(110 g/L≤Hb＜116 g/L)、偏高组(Hb≥124g/L)妇女所生儿童的语言智商得分分别为91.6±18.9、92.8±18.2、90.3±18.6;操作智商得分分别为104.7±15.2、104.5±14.3、103.5±15.1,全量表智商得分分别为97.8±17.3、98.4±16.3、96.4±17.4.调整混杂因素后,孕早期Hb偏高组妇女所生儿童低语言智商及低全量表智商得分的风险分别比孕早期Hb中等浓度组妇女所生儿童高54%(OR=1.54,95%CI:1.13～2.11)和53%(OR=1.53,95%CI:1.10～2.12),但未发现与儿童低操作智商得分风险存在统计学关联.母亲孕早期低Hb水平与儿童低语言、操作或全量表智商风险之间不存在统计学联系.结论 母亲孕早期过高的Hb浓度可能对其所生子女的语言智商有不利影响.

Influence of hemoglobin level during early gestation on the development of cognition of preschool children

Objective The purpose of this study was to evaluate the effect of hemoglobin (Hb) level during early gestation on the cognitive development of children at 4-6 years of age.Methods A total number of 3609 children were randomly selected from all the live birth infants whose mothers participated in a community intervention trial during 1993-1996 in 13 counties or cities in Jiangsu and Zhejiang provinces. Hb concentration during early gestation was measured at first prenatal examination and intelligence quotients (IQ), including full-scale, verbal and performance were assessed using Chinese-Wechsler Intelligence Scale for Children in 2000-2001 when these children had a mean age of 68 months. Results Compared with children whose mothers were non-anemic during early gestation, children whose mothers were anemic had a 0.6 point higher mean verbal scale IQ, a 0.9 point higher mean performance IQ and a 0.8 point higher mean full-scale IQ.These differences were not statistically significant when children' s gender, age at intelligence test,region, parity and mother' s IQ, education level and occupation were adjusted for. When mother-child pairs were divided into 5 sub-groups of every 20 percentiles according to Hb concentration during early gestation, verbal IQ scores of the lowest(Hb＜ 103 g/L), the moderate(110 g/L≤ Hb＜ 116 g/L)and the highest Hb concentration group (Hb≥124 g/L) were 91.6 ± 18.9, 92.8 ± 18.2 and 90.3 ±18.6, respectively. The performance IQ scores were 104.7 ± 15.2, 1 04.5 ± 14.3 and 103.5 ±15.1, and full-scale IQ scores were 97.8 ± 17.3,98.4 ± 16.3 and 96.4 ± 17.4, respectively. After controlling for confounding factors, children whose mothers had highest Hb concentration were 54% (OR= 1.54,95%CI:1.13-2.11)more likely to have poor verbal scores and 53% (OR= 1.53,95%CI: 1.10-2.12)more likely to have poor full-scale scores than children whose mothers had moderate -Hb concentration. No statistical associations were noticed between high -Hb concentration and performance scores, or between low Hb concentration during early gestation and verbal, performance as well as full-scale score of pre-school children. Conclusion High maternal Hb concentration during early gestation might adversely affect children' s cognitive development.