To investigate the value of ultrasonography in the diagnosis of fetal cleft lip and palate during early pregnancy and the correlation between interferon regulatory factor 6 (IRF6) gene polymorphism and fetal cleft lip and palate.

A total of 1659 fetuses of 11-13⁺⁶ weeks old admitted to the Department of Ultrasound, Panyu District Central Hospital between July 1, 2017 and December 31, 2018 were included in the study. The nuchal translucency (NT) measurement was performed, and the facial structure was examined. The mandibular arch cross-section with head lateral migration method was used to scan the fetal median sagittal section, mandibular arch cross-section, upper lip oblique coronal plane and postnasal triangle section for the diagnosis of fetal cleft lip and palate during early pregnancy. Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) was used to examine the single nucleotide polymorphism (SNP) of the IRF6 gene V274I loci in 5 fetuses with cleft lip and palate.

The display rate of the four sections in 1 659 fetuses was 95.0% (1 576/1 659) . There were 20 cases of cleft lip and palate, and the incidence was 1.2% (20/1 659) , the coincidence rate was 75% (15/20) , and the rate of missed diagnosis was 25% (5/20) . PCR-RFLP results showed mutation of IRF6 gene V274I loci in 2 fetuses with cleft lip and palate, and the mutation frequency was 3.2%.

Using mandibular arch cross-section with head lateral migration method to diagnose fetal cleft lip and palate during early pregnancy is simple, effective and feasible. The relationship between fetal cleft lip and palate and the polymorphism of IRF6 gene needs further study.

Early pregnancy; Fetal cleft lip and palate; Ultrasonography; RFLP-PCR; IRF6 gene polymorphism