27499
Melatonin and ethanol intake exert opposite effects on circulating estradiol and progesterone and differentially regulate sex steroid receptors in the ovaries , oviducts , and uteri of adult rats .
 Melatonin, ethanol, estradiol, progesterone, steroid
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: Chemical 
Text: {0} 
Answer:
 Melatonin, ethanol, estradiol, progesterone, steroid