中文摘要：

目的探讨瘦素在胎儿宫内生长发育中的作用，为代谢疾病的早期干预提供实验依据。方法连续入选2009年7月至2010年1月在北京协和医院出生的单胎足月新生儿266名（男婴140名，女婴126名），留取脐带血，出生后立即测量新生儿体重、身长、头围及胎盘重量。根据出生体重将新生儿分为低出生体重组（n=58，男婴25例，女婴33例）、正常出生体重组（n=180，男婴99名，女婴81名）和高出生体重组（n：28，男婴16例，女婴12例）。采用放射免疫分析法测定脐带血瘦素水平。采用独立样本t检验、Pearson相关分析、多元线性回归分析进行数据统计。结果与正常出生体重组[（9±5）μg/L]相比，低出生体重组脐带血瘦素水平[（7±5）μg/L]明显降低（t=3．216，P〈0．05），高出生体重组[（15±7）μg／L]明显升高（t=-4．026，P〈0．01）。女婴脐带血瘦素水平[（11±6）μg/L]明显高于男婴[（8±5）μg／L，t=一3．800，P〈0．01]。Pearson相关分析显示，脐带血瘦素水平与新生儿出生体重、身长、体质指数和胎盘重量呈显著正相关（r值分别为0．391、0．280、0．361、0．323，均P〈0．01）。校正母亲年龄、妊娠前体质指数、新生儿性别和胎龄后，脐带血瘦素水平仍与出生体重呈直线正相关（r2=0．289，P〈0．01）。结论脐带血瘦素水平与新生儿出生体重呈正相关，有望作为反映新生儿宫内生长发育的一个客观指标。

英文摘要：

Objective To explore the role of umbilical cord blood leptin in intrauterine growth so as to provide evidence for early intervention for metabolic diseases. Methods Two hundred and sixty-six healthy newborns （140 males, 126 females, gestational age 〉 37 weeks ） and their healthy mothers were enrolled in this study. Birth weight, birth length, head circumference, and ponderal index were measured before the neonates were assigned to low birth weight （LBW）, normal birth weight （NBW） and high birth weight （HBW） groups. The level of leptin in the umbilical cord plasma was assayed by radioimmunoassay （RIA）. Student＇s t test, Pearson correlation analysis and multi factor line regression were used for data analysis. Results Leptin was significantly decreased in the LBW group （ （7 ± 5） μg/L） and increased in the HBW group （（15 ±7） μg/L） when compared with the NBW group （（9 ±5） μg/L） （t values were 3. 216 and -4.026, respectively; both P〈0.05）. Leptin in female neonates （（11 ±6）μg/L） was significantly higher than that in male neonates （ （ 8 ± 5 ） μg/L） （ t = - 3. 800, P 〈 0. 01 ）. In Pearson correlation analysis, leptin was positively correlated with birth weight, height, body mass index （BMI） and placental weight （ r values were 0. 391, 0. 280, 0. 361 and 0. 323, respectively; all P 〈 0. 01 ）. After adjustment for maternal age, pre-pregnaney BMI, newborn gender and gestational age, leptin showed a liner relationship with birth weight. Conclusions The level of leptin in umbilical cord blood may be associated with birth weight and could be used as an indicator of intrauterine growth.