Plasma FXIII LEVEL Variations During Menstrual CYCLE

Factor XIII (FXIII) has an important role in the control of bleeding through fibrin cross-linking. While many physiological factors affect plasma FXIII level, the effect of the menstrual cycle is not fully understood.Aim: The study aimed to assess possible changes in plasma FXIII activity during the normal menstrual cycle and to assess any correlation between FXIII activity during the menstrual phase and the menstrual blood loss.

In this longitudinal study, a total of 32 women of reproductive age were recruited. Menstrual blood loss was measured using the pictorial blood-assessment chart (PBAC). A bleeding questionnaire and score were also completed. Blood samples were taken during menstrual phase (day 1-5), proliferative phase (day 6-11), periovulatory phase (day 12-17), secretory phase (days 18-23), and premenstrual phase (day 24-29) for assessment of FXIII level using quantitative ammonia release assay.

Mean FXIII level was significantly lowest during menstrual and periovulatory phases of the cycle (114 IU/dL) compared to secretory (121 IU/dL) and premenstrual (122 IU/dL) phases (p=0.036). No significant correlation between FXIII activity during menstrual phase and women age (p= 0.53) or PBAC score (p=0.53). Among 14 women with PBAC score ≥ 100, the median FXIII activity during the menstrual phase of the cycle was 116 IU/dL, this was not statistically different from group with PBAC score <100 (113 IU/dL) (p = 0.72).

FXIII activity was lowest during the menstrual and periovulatory phases of the cycle. Understanding these changes in FXIII during menstrual cycle will help clinicians to perform blood tests during appropriate phase of the menstrual cycle and to capture the baseline level.

Halimeh:Octapharma AG: Investigator Other, Research Funding.