The majority of hydrocystic tumors in fetuses are due to abnormalities in the fetal chromosomes, especially in Down’s syndrome or congenital heart disease, which may also occur. Hydrocysticercosis refers to the fetal nuchal translucency, also known as NT, the nuchal translucency is a special structure in the fetal period. The best time to measure the NT is between 11-13 weeks plus 6 days of gestation. there is a correlation between the thickness of the NT and specific diseases, and the thickness of the nuchal translucency can be measured to determine if the fetus is at risk for serious chromosomal abnormalities or heart disease. When the NT is greater than 3mm, a chromosome test or amniocentesis is recommended to determine if the fetus has Down syndrome.