Kirkegaard Ida, Obel Carsten, Hedegaard Morten, Henriksen Tine Brink
Department of Obstetrics, Aarhus University Hospital, Skejby Sygehus, 8200 Aarhus N, Denmark.
Pediatrics. 2006 Oct;118(4):1600-6. doi: 10.1542/peds.2005-2700.
Children born extremely premature (<28 weeks) or with a very low birth weight (<1500 g) have a poorer school performance than children born at term with a normal birth weight. Much less is known about children of higher gestational ages and birth weights. We studied gestational age after 32 completed weeks and birth weight in relation to the child's school performance at the age of 10 years.
We performed a follow-up study of 5319 children born between January 1990 and June 1992. We got the information on birth weight and gestational age from birth registration forms; when the children were between 9 and 11 years of age, we gathered information about their school performance (reading, spelling, and arithmetic) from questionnaires completed by the parents and the children's primary school teachers.
The association between birth weight and reading, as well as spelling and arithmetic disabilities, showed a graded relationship, with children who weighed <2500 g having the highest risks. Even children who weighed between 3000 and 3499 g had an increased risk of all 3 learning disabilities compared with children who weighed between 3500 and 4000 g. This association persisted after adjustment for potential cofounders and when the analyses were restricted to children born at term (39-40 weeks of gestation), suggesting that the association could not be explained by a low gestational age. Compared with children born at term, reading and spelling difficulties were more often found among children born at gestational age 33 to 36 weeks and 37 to 38 weeks, whereas there was no relation between gestational age and arithmetic difficulties.
Gestational age and birth weight were associated with school performance in the 10-year-old child and the association extended into the reference range of both birth weight and gestational age.
极早产儿（<28周）或极低出生体重儿（<1500克）的学业表现比足月出生且体重正常的儿童差。对于胎龄和出生体重较高的儿童，了解的情况要少得多。我们研究了32周完整孕周后的胎龄和出生体重与儿童10岁时学业表现的关系。
我们对1990年1月至1992年6月出生的5319名儿童进行了随访研究。我们从出生登记表中获取出生体重和胎龄信息；当儿童9至11岁时，我们从家长和儿童小学教师填写的问卷中收集他们学业表现（阅读、拼写和算术）的信息。
出生体重与阅读、拼写及算术障碍之间的关联呈现出分级关系，体重<2500克的儿童风险最高。与体重在3500至4000克之间的儿童相比，体重在3000至3499克之间的儿童出现所有三种学习障碍的风险也有所增加。在对潜在混杂因素进行调整后以及将分析仅限于足月出生（妊娠39至40周）的儿童时，这种关联仍然存在，这表明该关联无法用低胎龄来解释。与足月出生的儿童相比，胎龄在33至36周和37至38周出生的儿童更常出现阅读和拼写困难，而胎龄与算术困难之间没有关系。
胎龄和出生体重与10岁儿童的学业表现相关，且这种关联延伸至出生体重和胎龄的参考范围内。
