Does having a mesh that repaired a unbilical hernia afftect a pregnancy? can there be cimplication if birth is via csection?

Usually not: During the C-section your surgeon will avoid the area , most of the time is not a problem.

Should be OK: The umbilicus is key for the baby, but not for mom. A mesh repair should have no effect on your pregnancy provided you are not planning to have a repair while you are pregnant. A previous repair should be fine and a c-section is done lower on the abdomen so that should be ok also.