Scientists in Sweden and Britain found babies born extremely premature – fewer than 32 weeks of gestation – were three times more apt to develop the disorders and be hospitalized by 16 or older than babies who were born at term.
The researchers said the increased risk could be from small but very important differences in the development of the brain of babies that are born prior to the full gestation period of 40 weeks.
The risk was variable due to the condition. Psychosis was 2.5 times higher for babies born premature, severe depression was three times higher and bipolar disorder was 7 times higher for those babies born prior to 32 weeks of gestation.
The study also found significant but smaller risk of psychiatric disorders in babies that were moderately premature or born 32 to 36 weeks. The leader of the research, Chiara Nosarti from London’s King’s College said the results showed a definite link between psychiatric disorders and premature birth.
She said only the most severe cases were considered, which resulted in hospitalization, and that means in real terms the link could be even stronger. However, she stressed that the vast majority of children born premature have no cognitive or psychiatric problems and are well functioning and absolutely healthy.
The disorders only affect between one and 6% of the overall population as a whole.