A study of mothers and their young babies by neurologists at the University of California, San Francisco (UCSF) has shown that mothers who suffer migraine headaches（偏头痛） are more than twice as likely to have babies with colic（疝气） than mothers without a history of migraines. The work raises the question of whether colic may be an early symptom of migraine and therefore whether reducing stimulation may help just as reducing light and noise can alleviate（减轻，缓和） migraine pain. That is significant because excessive crying is one of the most common triggers for shaken baby syndrome, which can cause death, brain damage and severe disability.

"If we can understand what is making the babies cry, we may be able to protect them from this very dangerous outcome," said Amy Gelfand, MD, a child neurologist with the Headache Center at UCSF who will present the findings at the American Academy of Neurology's 64th Annual Meeting, which takes place in New Orleans in April.

Colic, or excessive crying in an otherwise healthy infant, has long been associated with gastrointestinal（胃肠的） problems -- presumably caused by something the baby ate. However, despite more than 50 years of research, no definitive link has been proven between infant colic and gastrointestinal problems. Babies who are fed solely breast milk are as likely to have colic as those fed formula, and giving colicky babies medication for gas does not help.

"We've known about colic for a really long time," Gelfand said, "but despite this fact, no one really knows why these babies are crying."