Menorrhagia is common in patients on oral anticoagulation with vitamin-k-antagonist phenprocoumon

No data are available for changes of menstrual blood loss in women on oral anticoagulation.

We assessed the menstrual blood flow of 46 women on long term oral anticoagulation  (OAC) with phenprocoumon in comparison to normal values from the literature. Menorrhagia is defined in the liturature as a (Pictural Blood loss Assessement Chart)PBAC score >100.
Design and methods:
Menstrual blood loss was assessed by a pictorial blood loss assessment chart (PBAC) over three menstrual cycles in each woman.

  • 34 women were on OAC due to thrombembolism and
  • 12 women for cardiac diseases (10 after prosthetic heart valve replacement, 2 with atrial fibrillation).
  • All women were on INR-self-management with a CoaguChekĀ® device.
  • 39 patients measured INR at least every two weeks, the others had longer control intervals (up to 6 weeks).
  • Medium age of the patients was 37,5 years.
  • The medium duration of OAC was 6,3 years.


  • 33 from 46 patients (72 %) had menorrhagia defined as a PBAC score > 100.  (Medium PBAC-Score of women on OAC was 191, ranging from 15 to 1064.)
  • Medium duration of menstrual bleeding was 6,5 days.
  • Medium cycle length was 27,8 days.
  • 4 of the women were taking oral contraceptives, two had an intrauterine device.


  • Menorrhagia, defined as a PBAC-score >100, is common in patients on OAC (72%). Patients on long-term OAC had an almost doubling of blood loss compared with normal controls.
  • There is a noteworthy undersupply of contraception methods to control bleeding and prevent pregnancy in women on OAC.
  • Control of menstrual bleeding is urgently needed in women onOAC.

Rott H, Halimeh S, Kappert G, Duisburg/Germany (November 2009)