The Bottom Line Age at toilet training has increased over time, very likely as a result of parents choosing to train later. Starting training earlier leads to earlier completion on average, although it generally takes longer; starting intensive training before twenty-seven months does not seem to lead to earlier completion. There is little evidence on the efficacy of child-led training versus more intensive, goal-oriented methods. Refusal to poop on the toilet is a common complication with some limited solutions.
