Now after every blow-job, I fill my mouth with sperm, then me and my husband share it 50-50, and swallow it joyfully. Initially we had some disgusting feeling but we keep on doing, now we both are accustommed and enjoying it. It is not at-all harmful.
But you must take care if there is any souring-boiling on your tongue or gums, you may avoid for time being.
Biologically sperm is just protin with some special ingreadient.
Do not worry keep swallowing and enjoy it specially...we are doing it since last 10 years....