11990
FSH and IGF - I synergistically stimulate gonadal steroid production ; conversely , silencing the FSH or the IGF - I genes leads to infertility and hypogonadism .
 Chemical: steroid
Please list all entity words in the text that fit the category.Output format is "type1: word1; type2: word2". 
Option: Chemical 
Text: {0} 
Answer:
 Chemical: steroid