Can meningocele develop in fetus of 25 weeks ? and if fetus was fine before?

When was before: Once the neural tube closes, a meningocele won't develop. However if the prior imaging was early in pregnancy, like at the time of a first trimester nuchal translucency scan, the spinal column might not be evaluated yet.

Meningocele: Yes a meningocele can develop, usually it is due to the fact that as the meningocele gets bigger it is easier to see on the ultrasonograms, meaning that it was likely there before but just not being seen on the imaging studies.