Vaginal sildenafil may be a therapeutic option for improving the chances of successful pregnancy in women with a history of recurrent miscarriage, study findings show. Malgorzata Jerzak (Military Institute of Health Sciences, Warsaw, Poland) and colleagues found that sildenafil citrate improved the quality of the endometrium and the immunologic environment in these patients.
For the study, 38 nonpregnant women with a history of recurrent miscarriage and 37 healthy women with previous successful pregnancies self-administered sildenafil suppositories 25 mg intravaginally, four times a day for 36 days. Peripheral blood natural killer (NK)-cell activity was significantly increased in the miscarriage patients compared with controls before treatment, at 15.67 versus 8.29 percent. But after vaginal sildenafil therapy, NK-cell activity was significantly reduced in the miscarriage patients by an average of 5.45 percent.
Endometrial thickness, which was significantly reduced in the miscarriage group compared with the control group, increased significantly after sildenafil therapy, from 8.06 mm to 9.25 mm.
"The mechanism of sildenafil's influence on NK cells is unknown; however, it can not be excluded that improvement in uterine artery flow has efficient influence on the local endometrial NK-cell population, and the diminished NK cell activity may promote successful pregnancy outcome," say Jerzak et al.
"Additionally, sildenafil significantly improves endometrial thickness, which is especially important in successful implantation."
