Girls, hi! At ultrasound at 33 weeks they said the large cyst of the b…

Girls, hi! At ultrasound at 33 weeks they said the large cyst of the brain increased by 14 mm. Have you encountered something like this? Doctors don't say much in the internet, there is nothing. Everything else is normal and develops according to schedule. What should I expect? What should I prepare for? They say it passes and isn't that scary but I am still very worried.