1162
The aim of this retrospective study was to investigate the impact of endogenous and exogenous luteinizing hormone ( LH ) activity on treatment outcome , when taking into consideration potential confounding variables .
 None
Given options, please tell me the categories of all the listed entity words.Output format is "type1: word1; type2: word2". 
Option: Chemical 
Text: {0} 
 Entities:  
Answer:
 None