Complex sentence: His wife is Svetlana Zakharova, the principal dancer of the Bolshoi Ballet, and they are currently expecting their first child, causing Zakharova to currently be on maternity leave from dancing.
Split into simpler sentences: His wife is Svetlana Zakharova, the principal dancer of the Bolshoi Ballet. They are currently expecting their first child, causing Zakharova to be on maternity leave from dancing.