Throughout the history of human civilizations, endogamy—the custom of marriages within communities of tribes, clans, extended families, and kin—has been common in many societies. These were consanguineous marriages between men and women who were closely related to each other.

These types of marriages were largely due to some historical, socio-economic, and cultural factors. They were practiced among the nobility, like kings, queens, and tsars. Commoners practiced consanguineous marriages for different reasons. Many families preferred their children to be married this way due to the advantages it offered in social and financial status. In these kinds of cultural settings, it is easier to maintain familial assets, structures, and alliances (Akrami et al., 2009; Hamamy, 2012; Shawky et al., 2011). 

What Are Consanguinity Marriages?

In consanguineous marriages, the man and woman marry each other within a circle of extended family and kin. Generally, in these cases, a potential partner is descended from the same ancestor as another person and belongs to the same kinship. They are the family members who are first cousins, first cousins once removed, and second cousins. Marriages between double first cousins are practiced among Arabs, and uncle-niece marriages are practiced in South India (Hamamy, 2012).

These are rarely cases of incest. Nevertheless, the substantial genetic similarities between spouses often cause the risk of inbreeding. Consanguinity in mating is a cause of a high rate of birth defects, stillbirths, abnormalities, and health complications in offspring (Heidari et al., 2016; Fareed & Afzal, 2014; Maghsoudlou et al., 2015).

Consanguineous Marriages in Modern Times

Nowadays, such consanguineous traditions in marriage have greatly declined in many modern societies. However, these marital relationships are still prevalent in some countries and communities across the world. According to some estimates, in the early 2000s, about 20% of the human population of the world still lived in communities practicing endogamy. And around 8.5% of children were born from consanguineous marriages (Akrami et al., 2009; Obeidat et al., 2010).

Consanguineous marriages are socially and culturally preferred among some communities across South India, West Asia, the Middle East region, and North Africa. They represent around 20–50% of all marriages in those societies. In these consanguine relationships, couples married to first cousins account for about one-third of all marriages (Bittles 2011; Hamamy, 2012; Heidari et al., 2014; El-Hazmi, Al-Swailem, Warsy, Al-Swailem, Sulaimani, & Al-Meshari, 1995; Tadmouri et al. 2009).

These cultural traditions of consanguinity have been enduring among emigrants from these cultural regions who now live in North America, Europe, and Australia. In their communities, the initiation of such relationships is also common.

These practices are more prevalent in rural areas where people are less educated. So, they are not aware of the inbreeding consequences for their offspring. Living in rural areas, they have low socio-economic status, low social mobility, and a large family size. They commonly marry at a younger age. Another reason is that these conditions cut down on the number of potential mates who could be good mating partners (Heidari et al., 2014; Masood et al., 2011; Sedehi et al., 2012; Tadmouri et al., 2009).

An Example of Consanguineous Marriages in Muslim Societies

In Muslim societies, cultural attitudes toward relationship initiation and marriage arrangements are very conservative. So, endogamous and consanguineous marital relationships are still relatively widespread. One such example is Saudi Arabian Muslim society.

Initiation of a marital relationship begins through matchmaking, in which personal kinship connections and consanguinity are preferred. Consanguinity arrangements are culturally highly important (Al-Dawood, Abokhodair, & Yarosh, 2017; El-Hazmi, Al-Swailem, Warsy, Al-Swailem, Sulaimani, & Al-Meshari, 1995).

Consanguineous Marriages Oppose Intercultural Relationships

Consanguineous marriages in the past have traditionally served the purposes of social and cultural preservation. In the cases of traditional conservative societies, they still work the same way despite the changing social contexts. The modern world is becoming more multicultural and intercultural in many regards, including intercultural marriages. The old tradition of consanguineous marriages continues to persist even when conditions have changed, like in modern America.

There is an increasing trend of intercultural marriages in America and many other societies become conducive to intercultural marriages.