Autumn Birth Linked to Childhood Brain Cancer
Study suggests in-utero springtime exposure to pesticides may be to blame
SATURDAY, April 2, 2005 (HealthDay News) -- Can the time of year you were born affect your chances of developing brain cancer?
Possibly, report Duke University researchers, who studied four different groups of medical records from various regions of the country and found that children born in late summer and fall were more likely to develop an aggressively malignant brain tumor called medulloblastoma.
"Medulloblastoma is more common in kids with autumn birthdates, even after correcting for the higher frequency of fall birthdays," said the study's lead author, Dr. Edward C. Halperin, vice dean of the school of medicine at Duke University Medical Center, in Durham, N.C.
Halperin and his colleagues suspect that something these children were exposed to in the womb during a period of crucial brain development may have contributed to their cancer. Pesticides are a prime suspect, he said, since they are commonly sprayed during the springtime.
Not everyone agrees, however. Dr. Mark Souweidane, vice chairman and director for pediatric neurological surgery at Weill Cornell Medical Center/New York-Presbyterian Hospital in New York City, said that while there "seems to be a marginally higher rate of children born with medulloblastoma in the fall, there's no good basis for saying that it's from pesticide exposure."
According to Halperin, other studies done in Norway and Japan have found an association between fall births and medulloblastoma. And, he added, other research has also shown a link between pesticide exposure and childhood brain cancers.
Medulloblastoma is the most common type of pediatric brain cancer tumor, according to the National Library of Medicine. Symptoms include headache, vomiting, uncoordinated movements and extreme fatigue.
For the current analysis, Halperin and his colleagues examined the medical records of nearly 1,200 children diagnosed with medulloblastoma between 1974 and 1999.
Ninety children were registered with the Central Cancer Registry, and information on 122 children came from a Duke University database. Information on 922 children came from the national Surveillance, Epidemiology and End Results (SEER) database, and details on another 75 Los Angeles-area children came from California SEER data.
The researchers compared birth data for the children with medulloblastoma to seasonal birth data from either North Carolina or from the National Center for Health Statistics.
They found that children with medullablastoma included in the Duke University database had significantly more autumn birth dates. Thirty-six percent were born in the fall, vs. 27 percent in the summer, 19 percent in the winter and 18 percent in the spring.
The statistics for the North Carolina group were similar, with 38 percent of children with medulloblastoma born in the fall, compared to 28 percent in the summer, 18 percent in the spring and 17 percent in the winter. The data from Los Angeles was also similar: 35 percent were born in the fall, 19 percent in the summer, 19 percent in the spring and 28 percent in the winter.
Only the national data didn't show an association between medulloblastoma diagnosis and autumn births. Halperin said he suspects that is because if you look at the nation as a whole, you are lumping together different geographic regions with different agricultural seasons.
Results of the study appear in the current issue of the Archives of Environmental Health.
Halperin stressed the results of this study don't mean "that people should stop spraying their crops or only drink bottled water," but the association between birth dates and cancer development is one worthy of further investigation.
To learn more about medulloblastoma and other types of primary brain tumors, visit the National Library of Medicine.