2534
DESIGN , SETTING , AND PARTICIPANTS : Population - based , multisite , case - control study of women who had pregnancies affected by 1 of more than 30 eligible major birth defects identified via birth defect surveillance programs in 10 states ( n = 13 155 ) and control women randomly selected from the same geographical regions ( n = 4941 ) .
 birth defects, birth defect
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: Disease, Chemical 
Text: {0} 
Answer:
 birth defects, birth defect