My Husband Is 59 Years Old And Recently He Has

My husband is 59 years old and recently he has been unable to ejaculate. He does not have erectile dysfunction or urinary issues and has no pain or discomfort. He simply is no longer able to complete sexual activity with an ejaculation. Is this an age related issue or a health concern? Can we overcome this or is he passing the age to be able to continue? Please advise.