Mars or Mangal is a planet that represents fire.
It causes a Dosha in the chart because it tends to burn the relationship
between a husband and wife; causing rift, tensions and in some cases
death of one spouse.However,
Mangala Dosha is not something that can be ignored. It does cause
marital discord. Before marriage it is very essential to match
horoscopes for Kuja Dosha. If a person has Kuja Dosha in the horoscope
the spouse must also have Kuja Dosha. This way the Dosha is cancelled.
Otherwise both should be without any Dosha.