Droste S, FitzSimmons J, Pascoe-Mason J, Shepard T H
Department of Obstetrics and Gynecology, University of Washington, Seattle 98195.
Am J Obstet Gynecol. 1990 Jul;163(1 Pt 1):158-61. doi: 10.1016/s0002-9378(11)90691-7.
Linear growth in fetuses with trisomy 18 has not been systematically described. We studied the relationship between long-bone, crown-rump, and foot length and gestational age in 17 postmortem fetal specimens with this syndrome. Long-bone and crown-rump lengths were compared with normal regression lines and foot length was compared with gestational age determined on the basis of menstrual dates. Correlation between foot length and menstrual dates was weak in trisomy 18. Gestational age predicted by crown-rump length was significantly lower than gestational age by menstrual dates. All long bones were significantly shortened and fell below normal regression lines for gestational age. The fetal femur/foot length ratio was reduced. Thus no endogenous measure of gestational age appears to exist in this aneuploidy, forcing reliance on menstrual dates. The observed pattern of growth alterations will likely preclude the development of a gestational age-dependent biometric screen for the prenatal detection of this syndrome.
18三体胎儿的线性生长尚未得到系统描述。我们研究了17例患有该综合征的死后胎儿标本中长骨、顶臀长度和足长与孕周之间的关系。将长骨和顶臀长度与正常回归线进行比较，将足长与根据末次月经日期确定的孕周进行比较。18三体中足长与末次月经日期之间的相关性较弱。顶臀长度预测的孕周显著低于根据末次月经日期确定的孕周。所有长骨均明显缩短，低于相应孕周的正常回归线。胎儿股骨/足长比值降低。因此，在这种非整倍体中似乎不存在内源性的孕周测量方法，只能依赖末次月经日期。观察到的生长改变模式可能会妨碍开发一种基于孕周的生物测量筛查方法用于该综合征的产前检测。
