Prenatal exposure to medicines and the risk of childhood brain tumor.
BACKGROUND
Childhood brain tumors are associated with high mortality and morbidity but little is known about its causes. About half of women use medicines when pregnant and some of the medicines commonly used might be carcinogenic.


OBJECTIVE
The aim with this population-based case-control study was to analyze associations between specific groups of medicines taken during pregnancy and the risk of brain tumor in the offspring.


METHODS
All children, up to 15 years of age, born in Sweden between 1975 and 1984 were eligible for the study. Cases (N=512) were children diagnosed with brain tumor and controls (N=525) were randomly selected from the Medical Birth Register. Exposure data on medicines was extracted blindly from antenatal medical records and grouped according to Anatomical Therapeutic Chemical (ATC) code. Information on maternal reproductive history was received from the Medical Birth Register. We used logistic regression to estimate associations between fetal exposure to medicines and childhood brain tumor.


RESULTS
No significant changes in risk were noted after exposure to iron supplementation, antiemetics, analgesics, antibiotics or any other main ATC group. A tendency of protective effect was seen for prenatal exposure to folic acid (adjusted OR 0.6, 95% CI 0.3-1.1). Ten children with a diagnosis of brain tumor had been exposed to beta-blocking agents in fetal life as compared to two children without brain tumor (adjusted OR 5.3, 95% CI 1.2-24.8).


CONCLUSIONS
In this case-control study, an increased risk of brain tumor was seen in children exposed to beta-blocking agents during fetal life. However, due to the low number of exposed the interpretation of this finding should be made with caution.
Stålberg
Karin
K
Department of Women's and Children's Health, Uppsala University, S-751 85 Uppsala, Sweden. karin.stalberg@kbh.uu.se
Haglund
Bengt
B
Strömberg
Bo
B
Kieler
Helle
H
D000293:Adolescent; D000328:Adult; D001932:Brain Neoplasms / Q000139:chemically induced / Q000453:epidemiology* / Q000473:pathology; D016022:Case-Control Studies; D002648:Child; D002675:Child, Preschool; D064420:Drug-Related Side Effects and Adverse Reactions; D005260:Female; D005865:Gestational Age; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D018811:Maternal Exposure / Q000009:adverse effects*; D011247:Pregnancy; D011297:Prenatal Exposure Delayed Effects; D011446:Prospective Studies; D012307:Risk Factors; D013548:Sweden / Q000453:epidemiology; D055815:Young Adult