Introduction: Sexual difficulties, and sexual pain in particular, represent a global health issue for women, and their prevalence has been shown to differ across countries.

Aim: To review the existing literature on the prevalence of female sexual difficulties and sexual pain worldwide measured by the Female Sexual Function Index (FSFI).

Methods: We conducted a systematic literature review based on the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Included were peer-reviewed publications indicating prevalence rates of female sexual difficulties based on the FSFI and cutoff values. Studies with samples limited to a certain age group or health condition were excluded.

Main outcome measure: The outcome measure includes cutoff values and prevalence rates for sexual difficulties and sexual pain, as well as sample characteristics.

Results: 22 studies conducted in 11 countries were included. These examined samples from the community, patient records, health care staff, or the Internet. Various prevalence cutoff values were applied. Prevalence rates of overall sexual difficulties ranged between 5.5% and 77%. For sexual pain, rates from 3% to 95.5% were found. A comparison between countries was restricted due to differences in sample size, sample type, and applied cutoffs. Representative community samples using comparable cutoffs found that 5.8-63.3% of women experience general sexual difficulty and 6-31.6% experience sexual pain.

Clinical implications: Sexual difficulties and sexual pain are prevalent in all examined countries, and despite restrictions to interpretability, the large prevalence rates point to the necessity of further clinical research.

Strength & limitations: Many studies had to be excluded because of missing data. The comparison of studies is descriptive, and not all regions worldwide are represented. Nevertheless, results of the review were useful to derive recommendations for reporting of future studies using the FSFI.

Conclusion: This review is the first comparison of prevalence studies based on the FSFI. It reflects the extent of available research and limitations in comparability. Koops TU, Briken P. Prevalence of Female Sexual Function Difficulties and Sexual Pain Assessed by the Female Sexual Function Index: A Systematic Review. J Sex Med 2018;15:1591-1599.