Menstruation is the most obvious phase in the menstrual cycle. Menstruating girls complain of an uncomfortable increase in menstrual flow when sugary solutions are ingested. This might be due to a quantitative change in factor 1. We therefore designed this research to study the effect of acute hyperglycemia on factor 1 during menstruation. We carried out the study amongst menstruating girls having obtained ethical clearance from the Ethical Committee and informed consent from the subjects for the study. Forty menstruating girls were selected randomly and were shared equally into two groups A and B. For group A, we induced acute hyperglycemia in twenty menstruating girls with oral ingestion of 39g/200mls dextrose water. For group B, we induced acute hyperglycemia in twenty menstruating girls with oral ingestion of 78g/200mls dextrose water. Blood sugar and factor 1 concentration were measured in three phases using standard approved methods in both groups. Phases IA and 1B were fasting blood sugar and fasting factor factor 1 concentrations. Phases IIA and IIB were random blood sugar and factor 1concentration 1hr post 39g/200mls dextrose water ingestion. Phases IIIA and IIIB were random blood sugar and factor 1concentration 2hrs post 39g/200mls dexstrose water ingestion. The blood sugar and factor 1 concentration for phases IA,IIA and IIIA were 84.12±3.14mg/dl and 3.55±2.56g/l; 141.12±3.14mg/dl and 3.01±2.24g/ ; 90.13±1.41mg/dl and 3.50±2.65g/l. There was a significant difference (p <0.05) in both blood sugar and factor1concentration between phases IA and IIA. The blood sugar and factor 1 concentrations for phases IB,IIB and IIIB were 86.17±3.16mg/dl and 3.53±2.54g/l; 161.22±3.34mg/dl and 3.03±2.22g/ ; 89.13±1.41mg/dl and 3.52±2.65g/l. There was a significant difference (p <0.05) in factor1 concentration between phases IB and IIB. No difference p>0.05 was observed in factor 1 concentration between phases IIA and IIB. Sugar depletes factor1 concentartion , thus reducing formation of fibrin and its hemostatic effect. Interestingly increasing dextrose water from 39g/200mls to 78g/200mls dextrose did not cause further depletion of factor1 concentration. Therefore, there might be a minimum concentration of glucose required to cause this depletion, above which no further depletion is observed. However, the minimum value of sugar required to cause this factor 1 depletion can be studied subsequently. Keywords: factor 1, menstruation, blood sugar