Sagotra or Sapravara is an important factor in the choice of groom or bride in arranged marriages. Gotra generally refers to a lineage, originating usually from a Rishi. The bride and the bridegroom should belong to different gotras, for a marriage to become admissible. Gotra, as a prohibitory factor, was unknown to society until 600 BCE. Puranas do not mention this factor. Vasudeva and Devaki both belonged to the same Satvata stock and hence the same gotra. The word gotra occurring in Vedic literature was used in the sense of a cow pen.
Some scholars believe that the prohibition of sagotra (the bride and the bridegroom belong to the same gotra) marriages became prevalent due to the influence of a cognate custom prevailing among the non-Aryans which interdicted marriages among the worshipers of the same totem. Some customs forbade marriage between close relatives also.
The prohibition first appeared in Grihya Sutra literature. A sagotra marriage was negatively viewed by smriti and nibandha writers. Gotras were originally mere surnames, and members of the same gotra have no real tie of consanguinity. Members of a gotra are also not always descended from one and the same seer (rishi) like Vasistha, Vishwamitra, and Bharadvaja. Some gotra names are territorial in their significance as, for example, Gandhara, Panchala and Kausambeya. May of them are professionals like Mesapa, Hastipa, Hota, Yajaka and so on.
Analyzing the origins of various gotras we find that gotras are probably not connected with descent from any Vedic seer, as it was believed, and hence it appears illogical to prohibit a marriage on that basis. A law in 1946 ended the bar on sagotra marriages, and the reform was welcomed.
Marriages among close relatives (pravara) were also discouraged. It was laid down that the parties to a marriage should not be sapindas, that is, related to each other within seven generations on the father’s side and four generations on the mother’s side. This rule was by and large ignored in South India. Viewed with our knowledge of the science of genetics, perhaps, this prohibition had some meaning.
Pravara means descent from a common ancestor, and marriages of persons belonging to the same pravara are not generally favored.