Down Syndrome Risk: Pregnancy at 48 with a Prior Affected Child

The chances of a mother with a Down syndrome child having another child with Down syndrome if she gets pregnant at age 48 are approximately 1 in 40.

Advanced maternal age is one of the most significant risk factors for having a child with Down syndrome. The risk increases as the mother ages, especially after age 35. At age 48, the risk is significantly higher than it is for younger mothers.

It is important to note that even though the risk is higher, the vast majority of mothers who have a child with Down syndrome do not go on to have another child with the condition.