In the study, blood and milk samples were taken from fifty-eight cows at 28, 30, 32 and 40 days after artificial insemination (AI). Transrectal ultrasonography (TRUS) was performed on all cows on days 30 and 40 after AI. Measurements were carried out on 9 cows whose pregnancy was confirmed and 9 cows whose embryonic mortality (EM) was determined. In PAG-Serum, there was a statistically significant difference (P <0.05, P <0.01) between the measurements on 40th day when EM was detected and on the 28th and 32nd days of pregnancy. In the PAG-Milk and PSPB-serum tests, there was a difference (P <0.05) in terms of blood values between the 32nd day and the 40th day when EM was detected. Statistically significant differences in PAG-Serum test (P <0.001) and PSPB test (P <0.01) was obtained between animals that were pregnant on the 40th day and animals that had EM on the 40th day according to TRUS observations. Sensitivity and specificity rates were determined in the tests as 22.2% vs 44.4% and 57.1% vs 77.8%, respectively, on the 40th day when embryonic mortality was detected. In the cows determined to be pregnant on the 30th day, the test results obtained on the day when EM was determined by the TRUS method on the 40th day and the diagnosis of EM were not individually reliable in every animal. However, it is thought that in between 28th day and 40th day, statistically significant difference (P<0.01; P <0.001 between the pregnant and EM animals can be predicted.