Hi,
Thanks for writing in.
Well, from your history it is clear that, there is problem in ejaculation although erection is normal.
There are several causes of delayed ejaculation or no ejaculation.
The most important cause is medication. This can be caused by antidepressants like SSRIs, medication used to control blood pressure and enlarged prostate. I would like to know if he is receiving any medication.
The next important cause would be neurological causes. Usually, there would be some other neurological symptom associated with difficulty ejaculating or some decrease in sensation. Urologists perform a test known as biothesiometry to determine if there is a sensory loss to the penis. Unfortunately, these neurological problems are often difficult to treat. (However, this seems to be unlikely in your husband's case)
Most importantly, a whole array of psychological problems could be responsible. This could be something as simple as performance anxiety to serious psychological inhibitions could be inhibiting your husband from achieving an orgasm. If he is able to ejaculate under other circumstances, like by himself, with hand or mouth stimulation by you, this variability suggests a psychological basis and he might consider being evaluated by a competent sex therapist.
I would suggest that your husband be evaluated by his treating physician. Once an evaluation has been completed, we can institute some proper management.
Regards,

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