Ovsynch yielded nearly one-third more pregnancies than cosynch, according to a recent study from the University of Wisconsin. Conception rate was 38.6 percent when AI occurred 16 hours after the second GnRH injection in the Ovsynch program versus 29.2 percent when CoSynch was utilized. That’s more than a nine-percentage-point improvement in conception rate versus breeding at the same time as the second GnRH in the CoSynch program, says Milo Wiltbank, professor of reproductive physiology at the University of Wisconsin. “I don’t think CoSynch is going to disappear, but you should know the risks,” Wiltbank said in March at the Western Dairy Management Conference in Reno, Nev.