The value of nuchal translucency thickness in the fetal chromosome abnormality screening / 实用医学杂志

ABSTRACT

Objective To evaluate the value of nuchal translucency (NT) thickness in the fetal chromosome abnormality screening. Methods 11 086 pregnant women received NT measurement in 11 ~ 13+6 weeks at Hainan general hospital from January 2010 to December 2014 were selected in the study. The NT thickness was measured according to guidelines from Fetal Medicine Foundation. 122 fetuses (NT≥2.5 mm) were recruited to accept karyotype analysis. Results 11 086 pregnant women received NT measurement in 11 ~13+6 weeks, in which 122 cases′ NT are more than or equal to 2.5 mm, with a positive rate of 1.10%. 122 cases of fetal NT thickening are between 2.5 to 12.0 mm, with the average degree at (4.5 ± 2.1)mm. 122 invasive prenatal diagnostic specimens chromosome karyotype analysis results showed chromosomal abnormalities in 21 cases (abnormal rate of 17.2%), the abnormal chromosome number in 17 cases and abnormal structure in 4 cases. The top 3 are trisomy 21 (12 cases, 57.1%), chromosome pericentric inversion (3 cases, 14.3%), and trisomy 18 (2 cases, 9.5%). Fetal chromosomal abnormalities resulting from different childbirth age, the sex of the fetus, NT thickness showed significant statistical difference (P < 0.05). The concrete manifestation is that fetal chromosomal anomaly detection rate in childbirth by women more than 35 years old age are higher than other age. Female fetal chromosomal anomaly detection rate is higher than the male , and NT thickness of 5mm of fetal chromosomal abnormality rate is significantly higher than the thickness of NT group at 2.5mm~ and 3.5mm~. Fetal NT thickening of NT measurements was in significant positive correlation with fetal chromosome abnormal rate (χ2=15.533, P < 0.001). Logistic regression analysis found that with a higher NT thickness , risk of fetal chromosomal abnormalities would be significantly higher , and thickening of NT could be an independent predictor of fetal chromosome abnormalities. Conclusion In early pregnancy, ultrasound examination of fetal ultrasound screening of NT thickness can be used as an important index of fetal chromosomal abnormality , and interventional diagnosis of prenatal NT thickness increase could pose increased risk of fetal chromosomal abnormalities.