Pakistan’s rate of consanguinity (the proportion of couples who are blood relatives) is unparalleled globally, with nearly two-thirds of marriages involving cousins. While cousin marriage rates have declined alongside economic development in many parts of the world, Pakistan’s rates have stayed roughly the same for several decades. Using data from the Punjab Consanguinity Survey, our new study provides a nuanced understanding of this phenomenon, contextualizing it within the frameworks of kinship, economic development, cultural norms, and demography.
Our findings identify three key factors that sustain high rates of cousin marriage in Pakistan: intensive kinship systems, slower economic development, and higher fertility rates. These factors combine to create a unique socio-economic environment in which the advantages of marrying within the family outweigh its drawbacks.
The study applies the framework of intensive versus extensive kinship networks. Intensive kinship systems, common in traditionally agrarian societies like rural Pakistan, favor reinforcing existing ties to ensure economic and social cooperation. Cousin marriages facilitate mutual support in agricultural and business, and allow families to consolidate wealth, maintain land ownership, and strengthen family alliances. In contrast, societies with extensive kinship networks prioritize building broader social connections, often through marriages outside the kin group. Extensive kinship systems are generally associated with economic development and modern market economies, where formal education becomes common, people often move for work or school, and social connections become key to market opportunities.
Consistent with the intensive kinship framework, we found that the number of cousins, whether parents had a cousin marriage, proximity between the spouses’ families, and norms of endogamy by caste or clan are associated with a higher likelihood of consanguinity. In contrast, the likelihood of cousin marriage decreases with extensive kinship indicators, including husband’s education, co-education, and substantial expenditures on weddings. For women, we also found that cousin marriages are often “marrying down” financially, keeping women’s wealth in the family.
We also find that high rates of cousin marriage are sustained by Pakistan’s high fertility rates, which result in a large pool of eligible cousins that allows the practice to be maintained across generations. Lower fertility rates have likely undermined the practice in neighboring countries and other regions that had high cousin marriage rates in the past.
Comparing Pakistan with neighboring India and Bangladesh, our paper highlights lower rates of literacy and female education alongside higher fertility and slower economic growth. These factors may help explain why cousin marriage rates in Pakistan greatly exceed those in the other major countries in the region. Globally, Pakistan’s patterns of cousin marriage share many similarities with countries in the Middle East and North Africa where similar socio-cultural and demographic conditions prevail.
While cousin marriages remain high in Pakistan, we also note emerging patterns that could disrupt the tradition over time. Higher education levels, especially for women, and increased urbanization are associated with lower consanguinity rates. Families engaged in market-based occupations rely less on kin for economic stability, reducing the incentive for cousin marriages. Moreover, exposure to diverse social networks is likely to increase rates of marriages outside the family. Finally, the demographic transition is likely to undermine kin marriages—as fertility rates decline, the number of eligible cousins diminishes rapidly, reducing the viability of the practice over time.
Understanding why cousin marriage persists in Pakistan is more than an academic exercise—it’s a window into the intersection of tradition, economy, demography, and modernity in one of the world’s most populous nations. We thus believe that situating cousin marriage, within broader kinship and development frameworks, can offer valuable insight for researchers, policymakers, and the general public.
About the Authors
Mary Shenk, Department of Anthropology, Pennsylvania State University, University Park, Pennsylvania, USA
Saman Naz, Department of Health Services Management and Policy, East Tennessee State University, Johnsonville, Tennessee, USA
Theresa Chaudhry, Department of Economics, Lahore School of Economics, Lahore, Pakistan