Reproductive Behavior and Health in Consanguineous Marriages

TLDR

Consanguineous marriages comprise 20–50 % of unions in many Asian and African regions and persist among migrants in North America and Europe; they are associated with higher fertility due to younger maternal age at first birth, yet may increase morbidity and mortality, and as medical advances shift disease burden toward genetic disorders, these communities face a greater risk of recessive disease expression. Studies show that only a minority of families in consanguineous populations experience the adverse effects of inbreeding.

Abstract

In many regions of Asia and Africa, consanguineous marriages currently account for approximately 20 to 50% of all unions, and preliminary observations indicate that migrants from these areas continue to contract marriages with close relatives when resident in North America and Western Europe. Consanguinity is associated with increased gross fertility, due at least in part to younger maternal age at first livebirth. Morbidity and mortality also may be elevated, resulting in comparable numbers of surviving offspring in consanguineous and nonconsanguineous families. With advances in medicine and public health, genetic disorders will account for an increased proportion of disease worldwide. Predictably, this burden will fall more heavily on countries and communities in which consanguinity is strongly favored, as the result of the expression of deleterious recessive genes. However, studies conducted in such populations indicate that the adverse effects associated with inbreeding are experienced by a minority of families.