Background: Antiphospholipid syndrome (APS) is a non-inflammatory autoimmune disease primarily characterized by thrombosis. Previous studies have indicated that disorders in proteins S and C, Factor V Leiden, and homocysteine levels can contribute to the occurrence of miscarriage in patients with APS. Objectives: This study aims to determine the prevalence of protein S, protein C, Factor V Leiden, and homocysteine disorders in patients with APS. Methods: This research was conducted as a retrospective study, utilizing the clinical information of patients who were referred to Golestan Ahvaz Hospital and whose records were available. A pre-prepared checklist was used to extract and record patients' clinical information, including demographic data, prevalence of miscarriage, vascular disorders (arterial and venous), pulmonary and venous thrombosis, preterm labor, intrauterine fetal demise (IUFD), intrauterine growth restriction (IUGR), and disorders or deficiencies of proteins C and S, as well as homocysteine levels. Results: In the present study, the results showed that a reduction in proteins C and S was observed in 18 (15.1%) and 20 (16.8%) patients, respectively. Thrombosis was present in 103 (86.6%) patients, and 27 (22.7%) patients had Aps Ab. The results indicated a statistically significant relationship between protein C deficiency, thrombosis, vascular events, and the presence of Abs in patients (P < 0.05) Additionally, a significant relationship was found between protein C deficiency and IUFD (P < 0.05). However, no significant relationship was observed between Aps Ab and IUFD or IUGR (P > 0.05). Conclusions: The results indicated that protein C can be used as a diagnostic factor in AP patients. Additionally, protein C was associated with IUFD in these patients.