You can find this study in the Journal of Sexual Medicine, published in September 2015:
Introduction
Men who are considering vasectomy as a means of contraception may have significant anxiety about their future sexual potency. As a result, couples may choose other forms of contraception with lower efficacy.
Aim
We sought to determine the relationship between vasectomy and the frequency of sexual intercourse.
Methods
We analyzed data from the National Survey of Family Growth to compare the frequency of sexual intercourse of men who had undergone vasectomy with men who had not. Analysis was performed using data from male and female responders, and excluded men who had never had sex and those below age 25. We constructed a multivariate logistic regression model to adjust for demographic, socioeconomic, reproductive, and health factors.
Main Outcome Measure
The main outcome measure was the sexual frequency in the last 4 weeks.
Results
Among male responders, a total of 5838 men met criteria for our study; 353 had undergone vasectomy. For vasectomized men, the average frequency of sexual intercourse was 5.9 times per month compared with 4.9 times for nonvasectomized men. After adjusting for age, marital status, race, education, health, body mass index, children, and income, vasectomized men had an 81% higher odds of having intercourse at least once a week compared with nonvasectomized men. A total number of 5211 female respondents reported 670 of their partners had undergone vasectomy. For partners of vasectomized men, the average frequency of intercourse was 6.3 times per month, compared with 6.0 times for partners of nonvasectomized men. After adjustment, women with vasectomized partners had a 46% higher odds of having sexual intercourse at least once a week compared with women with nonvasectomized partners.
Conclusion
Vasectomy is not associated with decreased sexual frequency. This finding may be helpful to couples as they consider contraceptive options.
Guo, D.P., Lamberts, R.W., & Eisenberg, M.L. (2015). Relationship between vasectomy and sexual frequency. Journal of Sexual Medicine, 12, 1905–1910.