产前超声测量胎儿肛殖距研究

Study on fetal anal pitch measured by antenatal ultrasound

目的:建立胎儿肛殖距(AGD)正常值参考范围,通过超声学方法验证AGD性别二态性,并分析AGD与孕周、胎儿体质量的关系。方法:收集20—39周正常产检胎儿627例,其中女310例,男317例,男性胎儿AGD测量从肛门中心到阴囊的底部间距离,女性胎儿AGD测量从肛门中心到阴唇后联合间距离。分析男性胎儿与女性胎儿AGD差异,胎儿AGD与孕周、体质量的相关性。以P<0.05为具有统计学差异。结果:各孕周男性胎儿AGD均大于女性胎儿AGD(P<0.05)。胎儿AGD与孕周呈线性相关,女性胎儿AGD(cm)=-0.945+0.068×孕周,相关系数r=0.868(P<0.01);男性胎儿AGD(cm)=-1.384+0.109×孕周,相关系数r=0.896(P<0.01)。胎儿AGD与估计体质量(EFW)呈线性相关,女性胎儿AGD(cm)=-0.453+1.870×EFW(kg),相关系数r=0.855(P<0.01);男性胎儿AGD(cm)=-0.785+1.280×EFW(kg),相关系数r=0.899(P<0.01)。结论:超声是有效的评价胎儿AGD的方法,同性别胎儿AGD与孕周、体质量呈线性正相关,胎儿AGD在两性之间存在二态性。

Objective: To establish the mormal range of prenatal anogenital distance(AGD). The gender dimorphism of AGD was verified by ultrasonography, and the relationship between AGD and gestational age(GA) and fetal weight was ana-lyzed. Methods: Six hundred and twenty-seven fetuses from 20 to 39 gestational weeks were collected, including 310 female fetuses and 317 male fetuses. The AGD of female fetuses were measured from the center of the anus to the posterior conver-gence of the fourchette and the AGD of male fetuses were measured from the centre of the anus to the base of the scrotum.The difference of AGD between male fetuses and female fetuses, and the correlation of fetal AGD with GA and weight were analyzed. P<0.05 was considered statistically significant. Results: AGD of male fetuses was higher than that of femal fetuses at all gestational weeks(P<0.05). Fetal AGD was linearly correlated with GA. Female fetuses AGD(cm)=-0.945+0.068×GA, coefficient of association r=0.868(P<0.01). Male fetuses AGD(cm)=-1.384+0.109×GA, coefficient of association r=0.896(P<0.01). Fetal AGD was linearly correlated with estimated weight(EFW). Female fetuses AGD(cm)=-0.453+1.870 ×EFW(kg), coefficient of association r=0.855(P<0.01). Male fetuses AGD(cm)=-0.785+1.280×EFW(kg), coefficient of association r=0.899(P<0.01). Conclusion: Ultrasound is an effective method to evaluate fetal AGD. Fetal AGD of the same sex had a linear relationship with GA and EFW, and the AGD showed dimorphism between the sexes.