正常中晚期妊娠羊水板层小体增长特征及其判断胎肺成熟的意义

目的探讨羊水板层小体数量在正常中、晚期妊娠的增长规律及其对判断胎肺成熟度的意义。方法采用自动血细胞计数仪血小板通道测量310份正常单胎妊娠16～42周的无污染羊水板层小体数目。结果羊水板层小体数目在32孕周前处于低值状态,其于16、24、31孕周时中位数分别为0、5×109/L、7×109/L;满32孕周时中位数达27×109/L,后增长速度开始逐渐加快;满37孕周时中位数为147×109/L。羊水板层小体数目与孕周呈正指数曲线相关,随孕周的增加呈指数增长,相关系数（r）为0.9386,确定系数（R2）为0.881。羊水板层小体数目对孕周的指数方程为Y（LBC）＋1=0.0273e0.2201X（孕周）（P〈0.0001）。利用指数模型预测36、37、38孕周的羊水板层小体数值分别为74×109/L、92×109/L、115×109/L。结论正常中晚期妊娠羊水板层小体数量随孕周进展呈指数增长,可利用板层小体数目对孕周的指数模型对胎肺成熟度做判断。

Investigation of Amniotic Fluid Lamellar Body Concentration Profile in Normal Mid-Late Trimester Pregnancy

Objective To observe the change of amniotic fluid lamellar body count （LBC） value during the second and the third gestation in normal pregnancy, and evaluate the LBC in assessment of fetal lung maturity.Methods From May 2007 to March 2009, amniotic fluid samples were obtained from 310 healthy women between 16th and 42nd gestational week.All specimens were taken by trans-abdominal amniocentesis or by cesarean section without blood or meconium contamination.Lamellar body counts were quantified with the automated hematologic cell counter （ABBOTT CELL-DYN 3700）.Results The quantities of amniotic fluid lamellar bodies increased as the gestation advanced.The quantities were low before 32nd gestational week, the median of LBC at the 16th, 24th, 31st gestational week were 0, 5×109/L and 7×109/L respectively.While its median was 27×109/L at the 32nd gestational week.The LBC was quickly increased progressively, and reached 147×109/L at the 37th gestational week.Lamellar body count was best represented as an exponential curvilinear function of gestational age.The function was Y （LBC） ＋1=0.0273e0.2201X（gestational age） （R2=0.881, P0.001）.Conclusion The quantities of amniotic fluid lamellar bodies increase exponentially as gestation advances in the second and third gestation in normal pregnancy.