However, a recent review of the evidence has found no clear association.
We found no association with mother's employment in the nuclear industry.
However, experimental studies have not always found an association, and the size of the effect can be very modest.
Other studies have found an association between smoking and strokes in men.
They also found an association between estrogen and the number of teeth lost.
Other studies, however, found no association between gun ownership and suicide.
The study found no association between older fathers and any other psychiatric conditions.
Millions of women began taking replacements after studies found an association between good health and their use.
Instead, the study found "no association at all, and even a suggestion of some protective effect".
But, once again, other studies found no such association.