I am Dr. Arun and will be helping you today.
I am sorry that your question was unanswered for long.
A finger exam of anus by doctor is a routine physical examination. This is termed digital rectal examination (DRE) or per rectal exam (PR). You may show the following resources to your husband, so he is convinced, that nothing inappropriate happened:
No patient enjoys it, your husband can take my word for it. Any stomach issue would warrant this exam and a patient in agony would majority of time does not even (distaste) like it.
Please feel free for your follow up questions.
I would be happy to assist you further, if you need any more information.
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