The use of frozen-thawed semen results in much lower fertility rates than the use of fresh semen. Although frozen semen has several benefits, such as bio-security, in that frozen semen can be tested for things like the PRRS virus so the inseminated herd is not infected. It has been suggested that seminal plasma can improve frozen-thawed semen performance. Also new timing techniques at ovulation and delivery of the seaman to the uterus instead of the oviducts, which is traditionally done, can help raise the fertility rates of frozen-thawed semen. These methods have potential to improve the chances of fertilization. Four separate experiments were carried out examining these methods by themselves and in combination. It was found that there was no advantage to adding seminal plasma to the semen, leading researchers to believe that freezing semen causes a degree of injury. Also the timing of insemination and process of insemination did not result in improved fertilization rates. More research must be carried out to be able to achieve full potential from frozen-thawed semen.