Background: Blood flow pattern among various women in different location of the world had been noted to vary significantly with some anthropometric variations, geospatial locations, age, BMI and cardiovascular parameters. As a result, this study therefore investigated the flow properties of blood during menstrual cycle in female undergraduate students in Port Harcourt as a baseline study with a view of establishing local reference data for Port Harcourt, Nigeria. Materials and Methods: 125 volunteers were recruited into the study using stratified random sampling techniques and were administered well-structured questionnaires. Their blood samples were collected and haemorheological properties (Whole Blood Viscosity, Plasma Viscosity, ESR and haematocrits) were analysed against various phases of menstrual cycle namely: menstruation, follicular, ovulation and luteal phases among female undergraduate students in Port Harcourt. Results and Discussions: Result of the study when compared with the WHO standard references showed a significant (ρ≤0.05) difference in ESR, PV, WBV and ESR for menstruation and follicular phases while HCT was not significant with ovulation and luteal phases. Flow properties was also significant (ρ≤0.05) with ages (16-23, 24-30 and ≥31) years as compared with the WHO Control. BMI and blood pressure was also significant (ρ≤0.05) with Haemorrheological properties of blood. Conclusion: The study therefore concluded that there is a significant (ρ≤0.05) correlation between flow properties of blood and phases of menstrual cycle among university students in Port Harcourt, Nigeria as compared with the WHO standard values.