husband orgasms without...

sometimes when my husband and I have sex, he orgasms without ejaculating. has anyone ever experienced this? lastnight my husband mentioned to me that he thinks his seamen is decreasing. not the sperm just how much he can go now. he just turned 40. and I'm alittle concerned, just hard when we use to be able to go like 3 or 4 times a week no problem. (not saying every week) but times like that to when we do it like the other day, it was every other day and he could ejaculate.

thoughts and experiences?

and before anyone says he jerks off or is having sex with someone else. my husband does not do that anymore. and I trust him. he is to busy for that. he works and if he isnt he is home. and never alone.