Is it too late to have first child at 35 - 36?

Talk to your doctor. But in general, 40 is considered the statistical cutoff for childbearing. As women get older, the statistical likelihood of the baby having some kind of congenital defect (Down's Syndrome is one of the most common) increases significantly.

Such a pregnancy should be monitored carefully and you may wish to have a genetic test performed during pregnancy to assess the baby's health.