Objective: Recent studies have shown changes in coagulation factors, suggesting an increased risk of thrombotic events, in women on progestin-containing contraceptives. To investigate this, we studied the effects of injectable depomedroxyprogesterone acetate (DMPA), given as a contraceptive, on coagulation and inflammation markers.
Design: Prospective nonrandomized study.
Setting: Department of Obstetrics and Gynecology, University of Vermont College of Medicine.
Patient(s): In this substudy of subjects undergoing a phase III trial comparing IM and SC DMPA, 14 healthy reproductive-age women were randomly assigned to receive either IM or SC DMPA every 3 months during a pharmaceutical trial.
Intervention(s): All subjects had blood samples obtained at baseline and 6 and 12 months.
Main outcome measure(s): D-Dimer, C-reactive protein (CRP), antithrombin (AT), factor VIIIc, activated partial thromboplastin time (aPTT), and aPTT plus activated protein C (APC) were analyzed on all samples.
Result(s): D-Dimer concentration was significantly decreased at 6 and 12 months with injectable DMPA compared t degrees o baseline. There was also a modest decrease in aPTT. The CRP, AT, factor VIIIc, and aPTT + APC were not significantly altered by the use of DMPA.
Conclusion(s): In this preliminary study the decline in D-dimer represents a potentially beneficial change in coagulation function following the use of DMPA given SC or IM. A slight decrease in aPTT may reflect a prothrombotic tendency with this contraceptive, but in contrast with previous studies examining the effect of oral contraceptive this injectable progestin contraceptive did not demonstrate the adverse effect on markers for thrombosis risk.