Pregnancy and delivery are known to raise the risk of stroke. But new research in the journal Neurology finds multiple births put extra strain and stress on blood vessels and other body systems.
Researchers say each additional birth is associated with a 27-percent greater risk of stroke due to bleeding in the brain.
One theory is that childbirth may somehow influence hardening or weakening of blood vessels.
According to researchers, the stress of simply raising children may also raise stroke risk.