Objective: To assess characteristics, incidence, risk factors, and reporting rate of needlestick injuries (NSIs) among Obstetrics and Gynecology trainees. Study design: We performed a nationwide cross-sectional survey study. The 40-items survey Obstetrics Needlestick Injury Questionnaire (ONSI-Q) was used to investigate the prevalence of NSIs, participant attitudes, associated factors, and the NSI reporting rate among trainees in Obstetrics and Gynecology. The target responders were all trainees of Obstetrics and Gynecology training programs in Italy. The trainees were invited between September 2018 and December 2018 via a web-based platform. Results: Among 1049 trainees, 1041 (99.2%) completed the survey. Out of 1041 trainees, 639 (61.4%) had at least one NSI, and 90.9% (581/639) experienced at least one during obstetric surgery. The number of NSIs increased with the year of training, with 2.48 NSIs per trainee in the fifth year. 90.6% (579/639) reported details about the most recent NSI, which was during obstetric surgery in 95.3% (552/579) of cases. 57.1% (315/552) experienced the most recent NSI during cesarean section, which was mainly inflicted by someone else (72.4%; 228/315). 42.9% (237/552) of NSIs were during perineal suture, and 84% (199/237) of them were self-inflicted. 77.9% (417/535) of trainees did not report the NSI. Associated factors were non-high-risk patients, self-inflicted NSI, and the first NSI. Conclusions: NSIs are frequent among Obstetrics and Gynecology trainees but not reported, and obstetric surgery is the primary source. These data support the European efforts to improve working practices' safety. The education about protective strategies and reporting should be a priority.