Causes and Consequences of Consanguinity in Bangladesh and Pakistan

Project Summary

An estimated 1,000 million people live in countries where 20-50+% of all marriages are contracted between couples related (generally second cousins or closer).  This estimate is deliberately conservative, since in many of the most populous countries, such as Indonesia and Bangladesh, very few studies have attempted to determine the current prevalence of consanguinity or its effects on population health. In an earlier household-based survey of the Teknaf region of Bangladesh, located in the extreme southeast of the country, which borders Myanmar, 17.6% of marriages were consanguineous.  However, there is limited literature that adequately accounts for the possibility of non-random selection into consanguinity for families with socio-economic characteristics that may also pre-dispose them towards a certain morbidity profile.  Given the confounding factors associated with consanguineous marriage and poor health, including poverty and lack of child immunization, the present multidisciplinary study was undertaken to investigate these social and economic influences on consanguineous marriage, and the survival and health effects of children born to such couples.

The situation was assessed in a retrospective survey of 5,208 pregnancies reported by 306 first cousin and 305 non-consanguineous marriages in which detailed information on socio-economic characteristics, specific health outcomes during pregnancy, infancy, and from 1-15 years was collected in 2006.  Using instrumental variables techniques that account for the fact that consanguineous marriages are only possible if a biological relative of the right gender and age is available, quasi-random variation in the incidence of first cousin marriages were generated to isolate the causal effect of consanguinity. 

Research Partners:

  • Bangladesh Project – Alan Bittles (Edith Cowan U., Australia), Murat Iyigun, Nizam Khan (University of Colorado).
  • Pakistan Project – Theresa Chaudhry (Lahore School of Economics)

Research Papers

  • A. M. Mobarak, R. Kuhn and C. Peters. “Consanguinity and other Marriage Market Effects of a Wealth Shock in Bangladesh,”Demography, 50(5): 1845-1871, October 2013
    Abstract: This paper uses a wealth shock from the construction of a flood protection embankment in rural Bangladesh coupled with data on the universe of all 52,000 marriage decisions between 1982 and 1996 to examine changes in marital prospects for households protected by the embankment relative to unprotected households living on the other side of the river. We use difference-in-difference specifications to document that brides from protected households commanded larger dowries, married wealthier households, and became less likely to marry biological relatives. Financial liquidity-constrained households appear to use within-family marriage (in which one can promise ex-post payments) as a form of credit to meet up-front dowry demands, but the resultant wealth shock for households protected by the embankment relaxed this need to marry consanguineously. Our results shed light on the socioeconomic roots of consanguinity, which carries health risks for offspring but can also carry substantial benefits for the families involved.


Related Media Articles on Consanguinity

  • Shaking Off the Shame, November 2009 (Link)
  • Cousin Marriage: Is it a Health Risk?, May 2008 (Link)
  • British MP is Criticized for Saying Marriage of First Cousins is a Health Problem, December 2005 (Link)
  • The Risk of Cousin Marriage, November 2005 (Link)
  • Gloucestershire Voices: Our Untold Stories, October 2003 (Link)
  • Iraqi Family Ties Complicate American Efforts, September 2003 (Link)
  • Few Risks Seen to the Children of First Cousins, April 2002 (Link)
  • Research Downplays Risk of Cousin Marriages, April 2002 (Link)