Does an employer have the right to prohibit an employee from donating blood?

I scheduled my blood donation on April 19th a month in advance. Today I was informed by my superior that it is completely forbidden to donate blood in April. Is it compliant with the Labor Code? I have sincere doubts about that. I will indicate that I am a production worker and my absence will not endanger the lives of other workers. I am asking for answers based on specific laws or legal grounds, as they will be useful in discussions with my superiors.

Thanks in advance for any answers.