Mangal Dosh is a common term in Vedic astrology and is considered a significant aspect while matching horoscopes for marriage. According to astrology, Mangal Dosh or Mars dosha occurs when the planet Mars is placed in the first, fourth, seventh, eighth, or twelfth house of a person's horoscope. Mangal Dosh is believed to bring inauspicious effects in one's married life, causing marital discord, delays in marriage, and sometimes even divorce.