Markestad T, Lossius P, Maartmann-Moe H, Iversen O E, Lie R T, Bergsjø P, Jacobsen G, Hoffman H J, Bakketeig L S
Department of Pediatrics, University of Bergen.
Acta Obstet Gynecol Scand Suppl. 1997;165:59-62.
The purpose of this study was to examine if placentas of small- for-gestational-age (SGA) and non-SGA infants differ with respect to proliferative cell activity.
Cell cycle distribution was studied in placentas from 181 SGA (birthweight < 10th percentile) and 528 non-SGA births by flow cytometry measurements of relative DNA content.
The fraction of cells in various cell cycle phases (G1-, S- and G2-phases) did not differ with gestational age from 30 to 43 weeks in either of the groups. The placentas of the SGA infants had a significantly lower mean (+/-1 SEM) growth fraction than placentas of non-SGA infants (S-phase 5.2 +/- 0.2 vs 5.5 +/- 0.1, p = 0.05, and G2-fraction 5.4 +/- 0.2 vs 6.3 +/- 0.1, p < 0.001), but the overlaps of the distributions were large. Thus sensitivity, specificity and predictive values of low fractions did not differ substantially-from a purely random prediction of SGA.
Cell division in the placenta is maintained until and beyond term. Placentas of SGA infants have on average, lower proliferative activity than placentas of non-SGA infants, but the difference is too small to be of predictive value in identifying intrauterine growth retardation.
本研究的目的是检验小于胎龄儿（SGA）和非小于胎龄儿的胎盘在增殖细胞活性方面是否存在差异。
通过流式细胞术测量相对DNA含量，研究了181例小于胎龄儿（出生体重<第10百分位数）和528例非小于胎龄儿出生的胎盘细胞周期分布。
在两组中，30至43周胎龄的不同细胞周期阶段（G1期、S期和G2期）的细胞比例均无差异。小于胎龄儿的胎盘平均生长分数显著低于非小于胎龄儿的胎盘（S期5.2±0.2对5.5±0.1，p = 0.05；G2期5.4±0.2对6.3±0.1，p<0.001），但分布重叠较大。因此，低分数的敏感性、特异性和预测值与单纯随机预测小于胎龄儿相比没有实质性差异。
胎盘细胞分裂维持至足月及以后。小于胎龄儿的胎盘平均增殖活性低于非小于胎龄儿的胎盘，但差异太小，对识别宫内生长迟缓没有预测价值。
