Patient: I am 8 months pregnant and the ultrasound shows that my baby’s renal collecting system in the left kidney area is separated by 16 MM. Now my baby is 7 months old (boy) nothing looks abnormal on the surface. Should I take the baby to the hospital for examination? If I go to the hospital, do I just need to have another ultrasound to make sure there is no problem? Specialist: Your child belongs to hydrocele detected during fetal period. As a rule, ultrasound examination is needed 3-7 days after birth. Fetal hydrocele has a tendency to spontaneously resolve, but it does not mean that all of them will resolve. In cases such as your child’s, according to our statistics, more than 20% require surgery within 2 years of age. There is no definite way to predict the need for surgery, but only through follow-up and observation of changes in the condition, which mainly includes ultrasound and isotope examination. Surgery is needed once there is urinary sensation, abdominal pain in large children, abdominal masses found by the doctor, etc. In addition, isotope nephrograms suggesting impaired or progressive decline in kidney function also require surgery. It is recommended that you go to a specialized hospital for relevant examinations.