Abstract and Introduction
Objective: The aim of this study was to determine the effect of sildenafil on the uterine circulation and clitoral artery blood flow in postmenopausal women using color Doppler sonography.
Methods: The study population consisted of 25 volunteer naturally postmenopausal women (mean age, 50.2 ± 3.6 years). Color Doppler sonography was performed to measure the resistance and pulsatility indexes of the uterine arteries and peak systolic velocity, resistance, and pulsatility indexes of the clitoral arteries. One hour after administration of a single oral dose of 50 mg sildenafil citrate, the Doppler sonographic examination was repeated.
Results: After sildenafil administration, the mean resistance and pulsatility indexes of uterine artery were significantly lower (0.73 ± 0.08 vs 0.80 ± 0.07, P < .001 and 1.66 ± 0.50 vs 2.08 ± 0.52, P < .001, respectively) in comparison to baseline values, and the mean peak systolic velocity of clitoral artery was significantly higher (17.9 ± 8.6 cm/sec vs 12.9 ± 5.8 cm/sec, P < .001). Sildenafil did not cause any significant change in the mean resistance and pulsatility indexes of the clitoral artery (P = .683 and P = .714, respectively).
Conclusion: Sildenafil improves the clitoral and uterine blood flow in healthy postmenopausal women without any erotic stimulus. Further studies are needed to determine whether there are roles for sildenafil therapy in postmenopausal women and evaluation of clitoral blood flow by Doppler sonography.
Female sexual dysfunction (FSD) is a multicausal and prevalent problem that can significantly affect the quality of life and interpersonal relationships of postmenopausal women.[1,2] Aging and the decline of ovarian hormonal secretion during the menopausal transition may alter libido and sexual response and functioning.[3,4,5] This decline relates more to decreasing estradiol concentrations than to androgen levels. In addition to hormonal changes, chronic diseases and medications may also negatively affect vascular response of the end genital organs. Potential therapeutic options for some categories of FSD include hormonal and pharmacologic agents.[7,8,9] Since nitric oxide (NO) synthase isoforms have been identified in the uterine and clitoral tissues, the NO–cyclic guanosine monophosphate (cGMP) pathway, which is involved in penile erection and enhanced by sildenafil,[12,13] may also play a role in some components of female sexual arousal response. Sildenafil has been demonstrated to be safe and effective in treatment of male erectile dysfunction.[13,14] However, there are little data about the influence of sildenafil on vascular hemodynamics of genital tissues in women. A single randomized placebo-controlled trial of sildenafil treatment for female sexual arousal disorder (FSAD) in postmenopausal women suggests that the agent may be effective for a select population of women (ie, without concomitant lack of sexual desire or contributory emotional, relationship, or historical abuse issues). Pfizer, the company that developed the drug, however, decided against seeking regulatory approval for its use in the treatment of FSAD because several large-scale placebo-controlled studies yielded inconclusive results.
Measuring penile blood flow by color Doppler sonography has become a first-line test for evaluation of erectile dysfunction, which is considered the male analogue to some components of FSAD. Clitoral blood flow measurements by color Doppler sonography may also be a reliable method to assess female sexual response. The purpose of this study was to determine the effect of sildenafil on the uterine circulation and clitoral artery blood flow in postmenopausal women, by color Doppler ultrasound.
© 2004 Medscape
Cite this: The Effect of Sildenafil Citrate on Uterine and Clitoral Arterial Blood Flow in Postmenopausal Women - Medscape - Oct 14, 2004.