My dh has infertility. Specifically, low morphology (4%) and low volume (0.5cc).
We were able to conceive our first after 9 months TTC, and the RE was very impressed that we were able to do it without further help.
Our second though, was more challenging. DH began taking several vitamins a day (E, C, B-Complex, Calcium, and a multi) and still no luck. The RE ran some blood tests, and found that DH has low testosterone and low FSH. So, she prescribed him 25 mg Clomid daily. He took the Clomid for 3 months, which boosted his FSH, which boosted his testosterone, which increased his morphology, but didn't really do much for the volume. (But even with the increased morph, it was still below the "normal" level. But hey, it was better than it was!)
However, DH is also on two medications (depakote and effexor) for a chronic condition, and the RE found a study that linked effexor with low ejaculatory response in women, so she said it's conceivable that the effexor was affecting his semenal volume. (His remained at 0.5cc, while normal levels are 2-6cc) To combat this, she prescribed him Viagra to take for BD'ing, in case the increased stimulation would increase semenal output.
Poor DH had to go in every 6 weeks for a semen analysis. But, after several months of his drug therapy (and 18 mos TTC) we finally got pregnant. The RE advised DH to remain on the Clomid until I was out of the "danger zone" in this pg, ie, out of the first tri.
Has your dh had a formal SA? What were his results?