Hi there and thank you for the question. I am a Registered Nurse and will be happy to help you today.
If you still have your ovaries and you still have a period (even an occasional period), you may be ovulating. If you do not have ovaries and you do not have periods any longer (menopause or hysterectomy), it could just be a nerve ending that is irritated. Other than that, peristalsis (contraction of the muscles in the GI tract) can often feel vibratory. Feelings like this is usually resolve on their own after a day or two and are self limiting. Annoying, but harmless nonetheless.