Rear view of a bride and groom during a wedding ceremony.Credit: Getty

NHS guidance that marrying your first cousin could have “benefits” despite a greater risk of birth defects has caused outrage.

The latest advice for suggests concerns about the risks of were “exaggerated” and “unwarranted” as “85 to 90 per cent of cousin couples do not have affected children.”

The training document, produced by England’s Maternity Transformation Programme, argues that “discouraging cousin marriage is inappropriate” as it was both “alienating and ineffective” and leads to “individuals feeling shamed and blamed”.

The guidance goes on to say that staff should not “stigmatise” predominantly South Asian patients for having a with as the practice is “perfectly normal” in some cultures.

It adds: “Marriage within the family can provide financial and social security at the individual, family and wider kinship levels,” noting that

“Pakistani women in cousin marriages have been found to compare favourably to those in non-relative marriages.”

But Oxford professor Patrick Nash said: “This is on par with recommending alcohol and smoking during pregnancy for their calming effects, while brushing over the absolutely horrendous consequences for the mother and child.

“There is no justification or excuse for this at all.

“Shame on the authors and shame on the Government for refusing to ban this indefensible cultural practice.”

Children of first cousins are more likely to experience worse educational outcomes, a 2024 study shows, while figures show up to 20 per cent of children treated for congenital problems were of Pakistani descent, compared to four per cent in the wider population.

Rear view of a bride and groom during a wedding ceremony.NHS guidance that marrying your first cousin could have ‘benefits’ despite a greater risk of birth defects has caused outrageCredit: Getty