Because of many variables affecting the quality of data collected by investigators, only generalizations can be made. Aside from infectious disease, causes of sow mortality include heart failure, cystitis, pyelonephritis, gastrointestinal problems (e.g. torsions, gastric ulcers), and complications during or shortly after parturition.
Individual sow condition and housing are important risk factors as well. Currently, sow welfare issues are promoting timely individual sow assessment and intervention to decrease overall sow mortality in the swine industry.