Introduction and Objective: Sacral nerve stimulation (SNS) has been shown to be effective in the treatment of retractable micturition symptoms (InterStim®, Medtronic Inc, Minneapolis, MN). Although the exact mechanism is not understood, therapy is felt to work by stimulating the S3 sacral nerve and modulating bladder function. The sacral plexus also plays an important role in modulating female sexual function (FSF)and response. The goal of this pilot study was to evaluate effects of the SNS on the female sexual response.
Methods: We conducted a retrospective multicenter study. All patients who had undergone a successful SNS implantation for voiding symptoms (frequency, urgency, urge incontinence or retention) were identified. They were asked to retrospectively evaluate their sexual function before the procedure and report on current sexual function. A number of instruments were used: (1) Female Sexual Function Index (FSFI) for overall global function, (2) Female Sexual Distress Scale (FSDS) a validated scale measuring the amount of sexually related personal distress, and (3) Female Intervention Efficacy Index (FIEI) which assesses changes in any component of sexual activity due to therapeutic intervention. Questionnaires were completed anonymously and without physician intervention.
Results: Twenty-eight patients consented to participate in the study; 17 reported they were sexually active. 17 patients completed the FSFI, an indicator of overall FSF (desire, arousal, lubrication, orgasm, satisfaction and pain). The mean score was 24.9 6.8 (excellent function=36, severe dysfunction=2). There was no significant decline in distress(p=0.16) after placement of the SNS, with a mean score change from 19.8 to 16.0 (maximum distress=48, no distress=0). On the FIEI, 35% of patients noted improvement in their overall sexual experience, 45% detected no change, and 18% a decline in function. Of those patients who noted improvement, most experienced this in terms of lubrication (29%), genital sensation (33%), improved intercourse (38%)and orgasm ability (19%).
Conclusions: Our results suggest that permanent SNS may positively impact female sexual function. It is unclear if this effect is due to a placebo effect, whether improving urinary symptoms leads to improvement in sexual life, or is direct S3 stimulation. It is also unclear why 18% of patients reported worsening sexual function. Prospective studies need to be conducted before the effect of SNS can be assessed.