对胎儿常见肢体畸形及少见复杂肢体畸形（海豹肢和人体鱼序列综合征）胎儿产前超声声像图特征进行总结分析。

采用连续顺序追踪超声法对2014年9月至2016年8月在解放军第一〇五医院产前超声筛查的18 708例胎儿行常规肢体和手足检查。与引产胎儿外观、影像检查及尸检结果对照，总结胎儿肢体畸形产前超声声像图特征。

产前常规和系统超声筛查检出胎儿肢体畸形76例（0.41%，76/18 708），包括：（1）前臂及手部畸形2例；缺指、多指、并指等手指数目异常11例；裂手畸形2例；手缺如2例；手姿势异常7例；（2）下肢及足部畸形：足内翻45例，海豹肢2例，人体鱼序列综合征1例；（3）四肢短小4例。其中孕14~19^＋6周胎儿肢体畸形超声检出率为0.69%（18/2627），孕20~27^＋6周超声检出率为0.46%（38/8195），孕20~27^＋6周超声检出率为0.40%（17/4237），均高于孕11~13^＋6周超声检出率（0.08%，3/3649）。76例肢体畸形胎儿中合并其他系统异常37例（包括颅脑、心脏、消化、肾脏、头面部及脊柱等）；其中染色体异常11例（21-三体2例，18-三体6例，13-三体3例）。76例肢体畸形引产胎儿标本外观检查均与产前超声检查结果一致，尸检（64例）证实产前超声仅遗漏1例胎儿左足多趾畸形。

早中孕期采用连续顺序追踪超声法筛查胎儿四肢及指趾，可及早发现胎儿肢体畸形，为临床处理提供诊断依据。

To summarize prenatal two-dimensional ultrasound examination results of different types of fetal limb deformity, and emphasise on some rare deformity disease such as phocomelia and sirenomelia. To investigate the value of systematic continuous sequence approach in the examination of fetal limb during pregnancy periods.

Eighteen thousand seven hundred and eight cases of fetus were selected from September 2014 to August 2016 in the 105^th Hospital of Chinese People′s Liberation Army, which were screened by routine and systematic ultrasonography. The systematic continuous sequence approach was used to focus on examination of the fetal limb. All fetuses with abnormal limbs were followed up. The ultrasonographic images were compared with the results of pathological examination and X-ray examination to summarize the ultrasonographic features of fetal limb deformities.

Seventy-six cases of fetal limb deformity were detected by prenatal ultrasound system in 18 708 cases. Three cases were detected at 11-13^{+ 6} weeks of gestation, 18 at 14-19^{+ 6} weeks, 38 at 20-27^{+ 6} weeks, 17 at 28-35^{+ 6} weeks. Types of limb deformities are as fllowing, 11 cases of abnormal number of fingers (adactylism, polydactyly, syndactyly), 2 cases of cleft hand deformity, 45 cases of foot varus, 1 case of sirenomelia and 4 cases of short limbs. Thirty-seven cases of fetal limb deformity combined with other system malformations and 12 cases were with multiple system malformations. Karyotypes were abnormal in 11 cases, including 3 cases of trisomy 21, 6 cases of trisomy 18 and 3 cases of trisomy 13. One case of prenatal ultrasound diagnosis of twins with sirenomelia. An autopsy of twin fetus indicated that there were epactal toes at the left foot. Prenatal ultrasonography.

The systematic continuous sequence approach in early and middle pregnancy play the advantages of each pregnancy examination. The fetal limb deformity can be detected early by combining application of systematic continuous sequence approach.