risk of Down's in relation to maternal age
The risk of having a baby with Down's syndrome is related to the age of the mother, approximately as follows:-
The levels of risk associated with having a Down's syndrome pregnancy in relation to a woman's age are shown in the table below:
Woman's age (years)
|Risk as a ratio||%Risk|
|45 and over||1.50 and greater||2.0|
If the mother of an affected child is under 36 then the risk of a further child being affected is said to be about 1 in 100.
Note however that the absolute numbers of mothers having children with Down's syndrome is greater in the younger age groups; this is because the total number of mothers in these groups is much higher.
For more information then see www.screening.nhs.uk/an
Last reviewed 04/2021