初产足月儿与经产足月儿宫内生长水平差异的研究

目的 制定不同胎龄初产足月儿与经产足月儿宫内生长百分位曲线，研究分娩产次对宫内生长潜力的影响。方法 采用整群取样法于2013年4月至2015年9月对深圳市两家医院出生的胎龄37~41周单胎足月儿进行体格生长现场测量。曲线拟合应用Lambda-Mu-Sigma（LMS）法。结果 获得了14 529例胎龄37~41周初产、经产足月儿各胎龄出生体重、身长、头围、胸围、顶臀长均值，并制定了其10th、25th、50th、75th、90th百分位曲线。经产足月儿上述5项指标的百分位曲线的形态和增长趋势与初产足月儿一致，但37~41周各胎龄经产足月儿上述5项指标的均值及百分位曲线值均高于初产足月儿。除胎龄41周组初产与经产组顶臀长比较差异无统计学意义外，其余各胎龄组5项指标均值比较差异均有统计学意义（P < 0.05）。结论 胎龄37~41周经产足月儿各胎龄体重、身长、头围、胸围、顶臀长5项指标宫内生长水平均高于初产足月儿，提示分娩产次是宫内生长潜力重要的影响因素。

Differences in intrauterine growth levels between full-term neonates born to primiparous or multiparous women

Objective To establish the intrauterine growth percentile curves of full-term neonates with different gestational ages (GAs) born to primiparous or multiparous women, and to investigate the influence of parity on intrauterine growth potential. Methods Cross-sectional cluster sampling was performed from April 2013 to September 2015 to measure physical growth in full-term singleton infants with a GA of 37-41 weeks in two hospitals in Shenzhen, China. The Lambda-Mu-Sigma method was used for curve fitting. Results The mean values of birth weight, body length, head circumference, chest circumference, and crown-rump length were obtained in 14 529 full-term infants. The 10th, 25th, 50th, 75th, and 90th percentile curves of the five indices were established. The full-term infants born to multiparous women had similar patterns and growth trends of the five percentile curves of the above five indices to those born to primiparous women, while the full-term infants with a GA of 37-41 weeks born to multiparous women had higher mean values and percentile curve values of the above five indices than those born to primiparous women. In the group with a GA of 41 weeks, there was no significant difference in the crown-rump length between the infants born to primiparous women and those born to multiparous women, but there were significant differences in the means of the above five indices in all the other GA groups between the two group infants (P < 0.05). Conclusions Full-term infants with a GA of 37-41 weeks born to multiparous women have higher intrauterine growth levels of birth weight, body length, head circumference, chest circumference, and crown-rump length than those born to primiparous women, suggesting that parity is an important influencing factor for intrauterine growth potential.