Genetic risk in related couples when planning pregnancy

People who are biologically related may have inherited the same gene change from a shared ancestor. If both partners carry a change for the same recessive condition, a pregnancy can be affected even when neither partner has symptoms. The actual concern depends on the degree of relation, each family’s history, ancestry, and testing results. Relatedness does not diagnose a condition and does not predict a particular outcome by itself.

Arrange a preconception appointment and bring information about relatives with childhood illness, developmental differences, unexplained infant deaths, repeated pregnancy loss, or known genetic diagnoses. A genetic counsellor can create a family history and explain whether carrier screening or a targeted test is useful. Discuss folic acid and routine pre-pregnancy care with your clinician. If pregnancy has already begun, counselling and appropriate testing can still be discussed; you do not need to wait for symptoms.

Seek specialist advice before conception when there is a known inherited condition, a previous child with a genetic diagnosis, several relatives with similar unexplained findings, or a family history of early childhood deaths. During pregnancy, contact your maternity team for questions about screening, diagnostic testing, or an abnormal result. Urgent pregnancy symptoms such as severe pain, heavy bleeding, or fainting need immediate clinical assessment and are not a measure of genetic risk.

Ask: Which relatives and diagnoses matter for our family history? Should both of us have carrier testing? What would a positive carrier result mean for a pregnancy? What screening and diagnostic choices are available, and when? How will our results be kept private?