Changes in the Hematological Parameters among Women Using Oral Contraceptives in Dhamar City, Yemen

Background: Oral contraceptives (OCs) are widely used, yet their hematological effects in resource-limited settings like Yemen, where anemia is highly prevalent, are poorly characterized. This study investigated the impact of OCs on hematological and coagulation parameters in women from Dhamar City, Yemen.Methods:A comparative cross-sectional study included 76 women (42 OC users, 34 non-users) recruited from healthcare facilities and community settings. Complete blood count parameters (hemoglobin, hematocrit, red cell indices, white cell differential) and coagulation markers (platelet count, prothrombin time, activated partial thromboplastin time [APTT], international normalized ratio) were measured. Statistical analyses included t-tests, Mann-Whitney U, chi-square, Spearman’s correlation, and multivariate logistic regression.Results:OC users showed significantly higher platelet counts than non-users (309.76 vs. 271.56 ×103/μL, p=0.024) and prolonged APTT (26.52 vs. 23.06 seconds, p=0.005), though all values remained within normal ranges. APTT correlated negatively with OC duration (rs=-0.452, p=0.004), decreasing from 28.9 seconds (1–2 years) to 25.3 seconds (>4 years). Microcytosis (MCV<80 fL) was more prevalent among OC users (42.9% vs. 20.6%, p=0.041, OR=2.89), despite similar hemoglobin levels. Younger users (<30 years) had higher platelet counts than older users (342.8 vs. 284.2 ×103/μL, p=0.004). Multivariate regression confirmed APTT (OR=1.202) and platelet count (OR=1.009) as independent correlates of OC use.Conclusion:OC use in Yemeni women is associated with elevated platelets, duration-dependent APTT changes, and increased microcytosis. These findings underscore the need for comprehensive hematological monitoring particularly platelet and coagulation profiles for OC users in anemia-endemic, resource-limited settings.