Fetal medicine is a branch of Obstetrics which delivers highly specialized diagnostics and treatments to pregnant women with complicated diseases of the unborn foetus. Types of diseases covered include genetic disorders, foetal abnormalities, twin pregnancy, etc. the purpose is to treat them in utero if possible or abort in time to avoid the birth of abnormal or handicapped children.
Procedures include detailed ultrasound examination, amniocentesis, chorionic villus biopsy, cordocentesis, etc. Sometimes amniotic fluid is taken out of the uterus and sent for genetic analysis also.
All these tests can help in determining any disease and taking appropriate action if required. We have a dedicated foetal medicine specialist working at our center who takes care of these problems regularly.
Choroid plexus is a gland in the baby’s brain which produces cerebrospinal fluid (CSF). This fluid bathes and protects the brain and spinal cord. In 1 to 2 % of babies, a small round fluid filled area (cyst) can be seen in the region of choroid plexus on ultrasound which is called choroid plexus cyst.
The exact cause of why choroid plexus cysts are formed in some babies is not known. It is just a collection of fluid and not an abnormality of brain matter by itself. More than 90% of choroid plexus cysts will resolve by 26 weeks.
Human beings usually have 46 chromosomes in pairs- one set of 23 chromosomes come from one parent while the other set of 23 chromosomes comes from the other parent. Babies with Trisomy 21 (Down syndrome) have 3 copies of chromosome 21 instead of the normal 2 copies. Similarly, babies with Trisomy 18 (Edward syndrome) have 3 copies of chromosome 18 instead of the normal 2 copies. The extra copy of chromosome affects how the baby’s body and brain develops and can cause physical and mental challenges for the baby. There have been reports to suggest that choroid plexus cysts are associated with increased risk of Trisomy 18 and possibly Trisomy 21. However, in majority of these cases, the baby’s ultrasound will show other abnormalities also.
If no other abnormality is present on ultrasound, in most cases no other tests are needed. However, if there are other abnormalities on ultrasound or your Dual test or Quadruple test shows a high risk for chromosomal abnormality, your doctor may suggest other tests like NIPT or Amniocentesis.
Studies have shown that children with choroid plexus cysts on ultrasound who have normal chromosomes do not show any difference in brain function and behavior after birth. In cases of isolated choroid plexus cysts, no additional tests are needed after birth.