Aim: The aim of this study is to determine the relationship between hyperemesis gravidarum and maternal serum pregnancy-associated plasma protein A (PAPP-A) and human chorionic gonadotropin (hCG) levels. This study was designed as a case-control study.,Methods: The study group consists of 54 pregnant women of 10-14 weeks who were diagnosed with hyperemesis gravidarum in the Istanbul Training and Research Hospital Hospital while the control group consists of 54 pregnant women of 10-14 weeks who did not have any complaints. Thyroid stimulating hormone, free T3, free T4, aspartate aminotransferase, alanine aminotransferase, PAPP-A, and hCG values and age were retrospectively scanned from files.,Results: We have observed that the hyperemesis gravidarum group has higher hCG levels as compared with the control group. The mean hCG level in control group and hyperemesis group was 1.10 +/- 0.569 and 1.55 +/- 1.140, respectively (p<0.05) The mean PAPP-A level in control group and hyperemesis group was 1.00 +/- 0.611, 1.36 +/- 0.887, respectively (p<0.05).,Conclusion: Elevated levels of PAPP-A and hCG are associated with hyperemesis gravidarum. More comprehensive studies are needed to explain the role of PAPP-A in the pathogenesis of hyperemesis gravidarum.