Levonorgestrel-intrauterine system effects on hemostasis and menstrual blood loss in women seeking contraception.

Aim: The purpose of the study is to determine the effects of levonorgestrel use on hemostasis, and menstrual blood loss over 24 months in a cohort of women seeking contraception.

Methods: Data from 30 women (median age 36 years) were analyzed. Samplings at pre-insertion, 1 and 3 months for blood and additional endometrial aspirates at 2 and 6 months were performed. Systemic determination for hemoglobin, hematocrit, computerized thromboelastography, tissue-type plasminogen activator, urokinase-like plasminogen activator and receptor, plasminogen activator inhibitor-1/2, D-dimer and von Willebrand Factor was performed. In endometrial extracts, tissue-type plasminogen activator, urokinase-like plasminogen activator and receptor and plasminogen activator inhibitor-1/2 were assayed. The Menstrual Blood Loss Pictorial Chart Score for measurement of menstrual blood loss was carried out for 24 months.

Results: There were no significant changes in systemic hemostasis within 3 months of device use. In the endometrium, there was a significant increase in tissue-type plasminogen activator antigen, plasminogen activator inhibitor-1/2 and urokinase-like plasminogen activator receptor levels from pre-insertion state, with the highest level seen by 6 months. Amenorrhea was seen in 20% of women by 6 months and 50% by 24 months.

Conclusions: Enhanced expression of plasminogen activator inhibitor-1/2 in the presence of increased urokinase-like plasminogen activator receptor and tissue-type plasminogen activator antigen was seen in the endometrium. The effects on hemostasis appear to be localized in the endometrium. Systemic hemostasis was not duly affected and menstrual blood loss was reduced. No women in the study had a pregnancy or expulsion of the levonorgestrel-intrauterine system device in the 24 months of the study period.