16588
CONCLUSIONS : Total , but not bioavailable , vitamin B12 stores were depleted during pregnancy to a greater extent in metformin - treated than in insulin - treated women with GDM , but neither analyte differed between groups at any stage .
 Chemical: vitamin B12; Chemical: metformin
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: vitamin B12; Chemical: metformin