Its not uncommon to have a low percentage of normal shaped sperm, particularly depending on how strict the criteria the lab is using. You probably want to get your partner checked out to see if he has a variocele, infection, or other reason for the low morphology.
Some reasons that can be remedied: smoking, drugs, alcohol, exposure to heat (ie sauna, hot tub), exposure to toxins, diet. New sperm are created every 3 months so a repeat SA after that time can show if there has been improvement. But I still read stories of people getting pg with low morphology.
Vitamins can help!