When I first started having sex with my boyfriend, I thought he was a fantastic lover, because he could keep going for hours. But I worry that he never climaxes. He says it's not a problem but I don't understand how it can't be, and feel he's holding back. When I use my mouth or my hands on him he loses his erection, so I've stopped trying. What's wrong with him - and how can I help?

He may be on prescription medication that inhibits climax (research the side effects online of anything that he is taking), in which case he could ask his doctor for a switch.

However, I suspect that he falls into a category of men who just happen to require intense stimulation to reach orgasm. Such men are appreciated by their partners for being able to thrust for long periods, so they hate revealing that they're not very aroused by vaginal intercourse, oral sex or light manual manipulation.

You can help by getting him to focus on receiving pleasure and feeling safe enough to be honest about what kind of stimulation does make him come. Then consider trying to accommodate that. Be prepared for the fact that his penis may require something like heavy friction with a rough towel - which you may learn to accomplish, or you could hold him while he finishes himself.

Once he gets used to ejaculating in your presence it's more likely that he will manage to do so inside you. Ideally, seek sex therapy - especially if you want to start a family soon.

· Pamela Stephenson Connolly is a clinical psychologist and psychotherapist who specialises in treating sexual disorders.

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