According to a new study published Wednesday in the Journal of Pediatrics, children who are born more than three months premature have double than expected rate of autism at age 2 compared to full-term children. The study was carried out by researchers at the Boston Medical Center in collaboration with the Boston University School of Medicine.

 

Autism is characterized by impaired social interaction and communication, and by restrictive and repetitive behaviour. These symptoms begin before the age of three. The disorder has a strong genetic basis, but the genetics of autism are complex and scientists don’t know for sure whether the disorder is determined by multigene interactions or by rare mutations.

 

The study, which included 1,000 children born at least three months early between 2002 and 2004, found that even among children with no pre-existing impairments, the chances of developing autism were about twice as high in those born three months early compared to children born at full term. The researchers used a checklist test called M-CHAT.

The test helped them determine if any of the babies had developed autism throughout their young lives.

 

The study found that about 1 in 10 of the babies who were born extremely premature and did not have other health problems, such as cerebral palsy, or mental impairment tested positive for autism at age 2.

The researchers suggested that the factors that cause a child to have autism also may force early birth. Those who were born at least three months prematurely also had motor, hearing or mental impairments, which can be linked with an increased chance of testing positive on the M-CHAT screening. Lead study investigator Dr. Karl Kuban, chief of the Division of Pediatric Neurology at Boston Medical Center, said that the test is not totally conclusive in determining whether a child will develop autism.

 

According to the study, 26 percent of children who were born extremely premature (before 27 weeks of gestation) had cognitive impairment, 11 percent were diagnosed with cerebral palsy, and 3 percent had problems with vision.

 

Preterm delivery is the leading cause of infant mortality and yet researchers and doctors don’t know what causes it. Premature babies have a higher risk of respiratory problems, neurological diseases, and the risk of early childhood mortality is up to seven times higher for preemies than for babies born at full term with normal birth weight.

About one in eight births in the U.S. is premature. Sixty percent of babies born at 26 weeks of gestation have long-term disabilities, such as chronic lung disease, deafness and neurodevelopmental problems.

 

There are a few steps that can be done in order to lower the premature birth rates, such as increased federal spending for prematurity prevention medical research, expanded access to health coverage for childbearing-age women, smoking cessation programs for mothers-to-be.