PREGNANCY LOSS IN CATTLE RANGES FROM 30 TO 56%, WHICH RESULTS IN AN ESTIMATED $87 MILLION ANNUAL LOSS TO THE U.S. CATTLE INDUSTRY. EMBRYOS DIE WHEN COMMUNICATION BETWEEN THE COW AND EMBRYO FAILS. OUR GOAL IS TO IDENTIFY THE INITIAL SIGNALS BETWEEN THE EMBRYO AND THE COW THAT RESULT IN PREGNANCY SUCCESS INSTEAD OF LOSS. FROM PREVIOUS WORK, WE KNOW THAT HORMONES CONTROL SOME OF THESE SIGNALS. OUR PLAN IS TO IDENTIFY HOW ONE OF THESE HORMONES, ESTROGEN, TURNS ON THE CORRECT SIGNALS FOR PREGNANCY SUCCESS. IDENTIFYING THESE KEY SIGNALS AND HOW THEY ARE TURNED ON WILL PROVIDE FUNDAMENTAL KNOWLEDGE TO DECREASE PREGNANCY LOSS.