Introduction: Current evidence suggests that annual simulation training is adequate to maintain skills for management of vaginal breech delivery. This study aimed to investigate whether skill levels declined at 6 months and further declined at 12 months after training. Methods: In this randomised single-blinded study, 12 obstetricians and 42 midwives were assigned at random to attend a 1-hour training session (lecture and simulation on singleton vaginal breech delivery) conducted at month 0 (control group) and at month 6 (intervention group). Their skill score was assessed before training (pre-test), immediately after training (at-test), and 12 months after training (post-test). Results: Compared with the pre-test score, skill scores increased immediately after the simulation training (at-test) in the intervention group (7.98 vs 15.03, p<0.001) and in the control group (6.86 vs 14.92, p<0.001). Compared with the attest score, skill scores decreased 6 months after the training (post-test) in the intervention group (15.03 vs 9.57, p<0.001) and 12 months after the training in the control group (14.92 vs 9.74, p<0.001). However, post-test skill scores were better than pre-test skill scores. The two groups were comparable in terms of the decline in skill score from attest to post-test (-5.49 vs-4.90, p=0.606). Conclusions: Simulation training results in short-term and long-term improvements in vaginal birth delivery skills. However, skill scores degrade over time and ongoing training at a minimum of 12-month interval is suggested for obstetricians and midwives.