Women with 16 or more sexual partners prior to marriage have an 80% rate of subsequent divorce.

A truism in psychology is that the best predictor of future behavior is past behavior. This is no less true in the realm of sexual behavior. Indeed, one of the strongest predictors of marital infidelity is one’s number of prior sex partners (Buss, 2000). Deception about past sexual promiscuity would have inflicted greater costs, on average, on men than on women

Haselton, M. G., Buss, D. M., Oubaid, V., & Angleitner, A. (2005). Sex, Lies, and Strategic Interference: The Psychology of Deception Between the Sexes. Personality and Social Psychology Bulletin, 31(1), 3–23. https://doi.org/10.1177/0146167204271303

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Regarding the correlates of infidelity, results indicated that on the basis of both methods of assessment, the probability of sexual infidelity increased with higher number of lifetime sexual partners

Whisman, M. A., & Snyder, D. K. (2007). Sexual infidelity in a national survey of American women: Differences in prevalence and correlates as a function of method of assessment. Journal of Family Psychology, 21(2), 147–154. https://doi.org/10.1037/0893-3200.21.2.147

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The high correlation for females (r = .79) between reported numbers of sex partners and EPC partners [extra-pair copulation partners def. sexual partners other than primary partner while in a monogamous relationship] may bear on questions of both paternity and abandonment in the face of infidelity.

[P]romiscuity is in fact a good predictor of infidelity. Indeed, promiscuity among females accounted for almost twice as much variance in infidelity (r2 = .45) as it did for males (r2 = .25).

Hughes, S. M. , & Gallup, G. G. (2003). Sex differences in morphological predictors of sexual behavior: Shoulder to hip and waist to hip ratios. Evolution and Human Behavior, 24(3), 173–178. https://doi.org/10.1016/S1090-5138(02)00149-6

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Individuals exhibiting sexually permissive attitudes and those who have had a high number of past sexual relationships are more likely to engage in infidelity (Feldman & Cauffman, 1999). In a study of supposedly exclusive dating couples, it was found that individuals exhibiting an ‘unrestricted’ sociosexual orientation (SO) were significantly more likely to pursue extra-pair involvement (Seal, Agostinelli, & Hannett, 1994). Individuals are said to be unrestricted if they score high on the Sociosexual Orientation Index (SOI). Items on this scale include a question tapping whether the respondent feels that love is a prerequisite for sexual relations with a partner, the number of ‘one-night stands’ a respondent has had, and how many partners he or she hopes to have in the next year (Simpson & Gangestad, 1991).

Barta, W. D., & Kiene, S. M. (2005). Motivations for infidelity in heterosexual dating couples: The roles of gender, personality differences, and sociosexual orientation. Journal of Social and Personal Relationships, 22(3), 339-360. http://dx.doi.org/10.1177/0265407505052440