Fetal left choroid plexus cysts can be a physiologic phenomenon, a common manifestation of fetal craniocephalic development, or there may be chromosomal abnormalities that need to be investigated.
During fetal cranial development, choroid plexus cysts are often seen on the left side of the brain, which is a visible phenomenon in cranial development with no adverse effects, and usually disappears normally in the 24th to 26th week of pregnancy.
Choroid plexus cysts need to be monitored by ultrasound. If the choroid plexus cyst does not disappear in time and shows signs of gradual increase in size, and the ultrasound reveals overlapping fingers or clenched fists, further chromosomal screening is needed to detect various chromosomal anomalies causing fetal craniocerebral malformations.