Consanguinity refers to when both members of a couple are related to each other by at least one common ancestor.
We all have two copies of almost every gene - one from each parent. In autosomal recessive (AR) conditions, it is typically necessary to have two mutations, one in each gene copy, to be affected. People with only a mutation in a single gene are called carriers, and typically do not have any symptoms of the condition.
It is believed that we all are carriers of at least 8-10 different autosomal recessive conditions. The chance that both members of a couple are both carriers of the same AR condition is increased if they are related to one another, as they each could have inherited a mutation from the same common ancestor.
To give some background information, the general population risk for two non-related people to have a child with a birth defect is estimated at 3-4%. In the absence of a known autosomal recessive condition in a family, the risk for first cousins to have a child with a birth defect is believed to be doubled, 6-8%.
We recommend that you and your partner meet with a genetic counselor, who can review your ethnic backgrounds, as well as your personal and family health histories to provide risk assessment specific to your situation. A genetic counselor can also discuss the benefits and limitations of any available genetic testing options. You can find a genetic counselor through the National Society of Genetic Counseling website or through companies like mine, AccessDNA.