Prenatal limb defects: Epidemiologic characteristics and an epidemiologic analysis of risk factors

To analyze prenatal ultrasound data for fetal limb deformities in high-risk pregnant women and the risk factors for prenatal limb defects in high-risk pregnant women. This was a retrospective study of high-risk pregnant women at the multidisciplinary consultation center from January 2006 to December 2015. When deformities were definitively diagnosed in the first trimester by ultrasound, patients were recommended to undergo an abortion, and fetal abnormalities were confirmed by pathological examination (both gross anatomic examinations and fetal chromosome and genetic tests). The risk factors for fetal limb deformities and other congenital malformations were analyzed by multifactor analysis. Of the 4088 fetuses recorded, 144 (3.52%) were diagnosed with limb abnormalities. The abnormalities included 70 (48.61%) clubfoot/clubhand cases, with 5 polydactyly, 5 syndactyly, 4 flexion toe, 4 split hand/foot malformation, 3 overlapping fingers, and 49 congenital talipes equinovarus. A total of 6 (4.17%) and 13 (9.02%) fetuses had phocomelia and imperfect osteogenesis, respectively; 22 (15.28%) cases showed achondrogenesis; 19 (13.19%) and 12 (8.33%) had partial limb deletion absence and joint movement malfunction, respectively. In the high-risk population with limb deformities (144 patients), 19 (13.19%) were ≥35 years old, 6 (4.17%) had family history of congenital malformations, 14 (9.72%) had abnormal reproductive history, 21 (14.6%) had harmful chemical exposure, 6 (4.2%) had early TORCH infections, 16 (11.1%) had gestational diabetes, 9 (6.3%) had hypertension, 3 (2.1%) took glucocorticoid, 9 (6.3%) took sedatives. In the high-risk population with other congenital malformations except limb deformities (3766 patients), 144 pregnant women were randomly selected. In the high-risk population with other congenital malformations (144 patients), 9 (6.25%) were ≥35 years old, 7 (4.86%) had family history of congenital malformations, 10 (6.94%) had abnormal reproductive history, 22 (15.28%) had harmful chemical exposure, 5 (3.47%) had early TORCH infections, 12 (8.33%) had gestational diabetes, 11 (7.64%) had hypertension, 4 (2.78%) took glucocorticoid, 11 (7.64%) took sedatives. Ultrasound can provide adequate evidence for fetal limb deformities evaluation in most patients. Fetal limb deformity cases showed a significantly higher rate than other congenital malformations for advanced maternal age (≥35 years old).