In the sentence extracted from biomedical literature, identify all the chemical entities. The required answer format is the same sentence with HTML <span> tags to mark up specific entities. 
### Entity Markup Guides:
Use <span class="chemical"> to denote a chemical.

### Input Text: The treatment schedule consisted of conjugated estrogens ( Premarin ) 1 . 25 mg / day for 21 days and Medroxyprogesterone acetate 10 mg / day for 10 days in each month .
### Output Text:
The treatment schedule consisted of <span class="chemical">conjugated estrogens</span> ( <span class="chemical">Premarin</span> ) 1 . 25 mg / day for 21 days and <span class="chemical">Medroxyprogesterone acetate</span> 10 mg / day for 10 days in each month . 