Research suggests that late-night babies or those born in the wee hours of the morning have a higher risk of developing certain rare brain problems, noting that each year more than 10,000 babies die in the U.S. due to cerebral palsy.

Earlier research has already linked such births with other such outcomes, including death.

However, none are clear about whether the timing of the birth might play a role in neonatal encephalopathy, lead researcher Dr. Yvonne W. Wu of the University of California School of Medicine, San Francisco said.

About 2 million term babies born in California during a 14-year period were taken for study and researchers noted that about 1.1 per 1,000 births had such brain problems. About 16 per cent of them often died before a month ended. Those babies born between 10 P.M and 4 A.M had a 22 per cent higher risk, than the ones born during the day.

Researchers also noted that boys were at a higher risk, and kids of bothers who over 35 years of age were at higher risks. "In most cases, the underlying cause is unclear," said Wu.

Researchers were also not in a position to suggest any preventive measures to avoid such problems with brain development of babies. "Cooling the baby's body temperature appears to protect the brain, and may lead to better long-term neurologic outcomes," Wu said. Researchers considered the condition extremely rare. "It is very common for babies to be delivered at night," said Wu. "And the vast majority of babies born at night will have no complications."