The authors selected 5000 singleton pregnancies (11-13 weeks+6 weeks) who underwent combined screening in a hospital from January 1, 2010 to December 31, 2011, and examined fetal nuchal translucency (NT) thickness, nasal bone loss, venous catheter a-wave flow reversal and tricuspid regurgitation using ultrasound; they also measured maternal serum pregnancy-associated protein A (PAPP A) and free β-chorionic gonadotropin (β-hCG) levels were measured. NT values and β-hCG and PAPP-A levels were entered into the computer and risk values (≥1:270) were calculated. A total of 204 high-risk cases were screened out of 5000 pregnant women in the combined screening. Chorionic villus tissue biopsy was performed in these 204 cases to detect fetal karyotype, and ultrasound characteristics of chromosomally abnormal fetuses were analyzed. RESULTS: It was found that the detection rate of combined screening of fetuses at 11-13 weeks +6 weeks of gestation was high and the false positive rate was low; abnormal karyotype fetuses were often associated with tricuspid regurgitation, a-wave reversal of venous ducts and nasal bone defects, and increasing ultrasound markers had the effect of improving the detection rate of abnormal fetuses; abnormal ultrasound markers at 11-13 weeks +6 weeks of gestation may be associated with fetal congenital heart disease.