Consanguineous Marriage (Maternal Cousins): Genetic Risks and Counseling

Quantitative Risk

• Background risk of serious genetic disorder: ~2–3%.
• First‑cousin offspring: ~4–6% (doubled).
• Risk correlates with coefficient of inbreeding (F = 0.0625 for first cousins).

Blood Type Irrelevance

Shared ABO/Rh type does not indicate genetic relatedness or disease risk.

Pre‑Conception Counseling

• Three‑generation pedigree analysis.
• Carrier screening for population‑specific recessive conditions.
• Discuss prenatal diagnostic options (CVS, amniocentesis) and reproductive alternatives (IVF+PGT‑M).

Genetic counselors provide personalized risk assessment and nondirective support.